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1611.07573
Manuel Isaac Martinez Torres
Manuel Martinez, Monica Haurilet, Ziad Al-Halah, Makarand Tapaswi, Rainer Stiefelhagen
Relaxed Earth Mover's Distances for Chain- and Tree-connected Spaces and their use as a Loss Function in Deep Learning
null
null
null
null
cs.CV
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The Earth Mover's Distance (EMD) computes the optimal cost of transforming one distribution into another, given a known transport metric between them. In deep learning, the EMD loss allows us to embed information during training about the output space structure like hierarchical or semantic relations. This helps in achieving better output smoothness and generalization. However EMD is computationally expensive.Moreover, solving EMD optimization problems usually require complex techniques like lasso. These properties limit the applicability of EMD-based approaches in large scale machine learning. We address in this work the difficulties facing incorporation of EMD-based loss in deep learning frameworks. Additionally, we provide insight and novel solutions on how to integrate such loss function in training deep neural networks. Specifically, we make three main contributions: (i) we provide an in-depth analysis of the fastest state-of-the-art EMD algorithm (Sinkhorn Distance) and discuss its limitations in deep learning scenarios. (ii) we derive fast and numerically stable closed-form solutions for the EMD gradient in output spaces with chain- and tree- connectivity; and (iii) we propose a relaxed form of the EMD gradient with equivalent computational complexity but faster convergence rate. We support our claims with experiments on real datasets. In a restricted data setting on the ImageNet dataset, we train a model to classify 1000 categories using 50K images, and demonstrate that our relaxed EMD loss achieves better Top-1 accuracy than the cross entropy loss. Overall, we show that our relaxed EMD loss criterion is a powerful asset for deep learning in the small data regime.
[ { "version": "v1", "created": "Tue, 22 Nov 2016 22:54:05 GMT" } ]
2016-11-24T00:00:00
[ [ "Martinez", "Manuel", "" ], [ "Haurilet", "Monica", "" ], [ "Al-Halah", "Ziad", "" ], [ "Tapaswi", "Makarand", "" ], [ "Stiefelhagen", "Rainer", "" ] ]
TITLE: Relaxed Earth Mover's Distances for Chain- and Tree-connected Spaces and their use as a Loss Function in Deep Learning ABSTRACT: The Earth Mover's Distance (EMD) computes the optimal cost of transforming one distribution into another, given a known transport metric between them. In deep learning, the EMD loss allows us to embed information during training about the output space structure like hierarchical or semantic relations. This helps in achieving better output smoothness and generalization. However EMD is computationally expensive.Moreover, solving EMD optimization problems usually require complex techniques like lasso. These properties limit the applicability of EMD-based approaches in large scale machine learning. We address in this work the difficulties facing incorporation of EMD-based loss in deep learning frameworks. Additionally, we provide insight and novel solutions on how to integrate such loss function in training deep neural networks. Specifically, we make three main contributions: (i) we provide an in-depth analysis of the fastest state-of-the-art EMD algorithm (Sinkhorn Distance) and discuss its limitations in deep learning scenarios. (ii) we derive fast and numerically stable closed-form solutions for the EMD gradient in output spaces with chain- and tree- connectivity; and (iii) we propose a relaxed form of the EMD gradient with equivalent computational complexity but faster convergence rate. We support our claims with experiments on real datasets. In a restricted data setting on the ImageNet dataset, we train a model to classify 1000 categories using 50K images, and demonstrate that our relaxed EMD loss achieves better Top-1 accuracy than the cross entropy loss. Overall, we show that our relaxed EMD loss criterion is a powerful asset for deep learning in the small data regime.
no_new_dataset
0.949106
1611.07579
Sameer Singh
Sameer Singh and Marco Tulio Ribeiro and Carlos Guestrin
Programs as Black-Box Explanations
Presented at NIPS 2016 Workshop on Interpretable Machine Learning in Complex Systems
null
null
null
stat.ML cs.AI cs.LG
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Recent work in model-agnostic explanations of black-box machine learning has demonstrated that interpretability of complex models does not have to come at the cost of accuracy or model flexibility. However, it is not clear what kind of explanations, such as linear models, decision trees, and rule lists, are the appropriate family to consider, and different tasks and models may benefit from different kinds of explanations. Instead of picking a single family of representations, in this work we propose to use "programs" as model-agnostic explanations. We show that small programs can be expressive yet intuitive as explanations, and generalize over a number of existing interpretable families. We propose a prototype program induction method based on simulated annealing that approximates the local behavior of black-box classifiers around a specific prediction using random perturbations. Finally, we present preliminary application on small datasets and show that the generated explanations are intuitive and accurate for a number of classifiers.
[ { "version": "v1", "created": "Tue, 22 Nov 2016 23:35:03 GMT" } ]
2016-11-24T00:00:00
[ [ "Singh", "Sameer", "" ], [ "Ribeiro", "Marco Tulio", "" ], [ "Guestrin", "Carlos", "" ] ]
TITLE: Programs as Black-Box Explanations ABSTRACT: Recent work in model-agnostic explanations of black-box machine learning has demonstrated that interpretability of complex models does not have to come at the cost of accuracy or model flexibility. However, it is not clear what kind of explanations, such as linear models, decision trees, and rule lists, are the appropriate family to consider, and different tasks and models may benefit from different kinds of explanations. Instead of picking a single family of representations, in this work we propose to use "programs" as model-agnostic explanations. We show that small programs can be expressive yet intuitive as explanations, and generalize over a number of existing interpretable families. We propose a prototype program induction method based on simulated annealing that approximates the local behavior of black-box classifiers around a specific prediction using random perturbations. Finally, we present preliminary application on small datasets and show that the generated explanations are intuitive and accurate for a number of classifiers.
no_new_dataset
0.945197
1611.07623
EPTCS
Maaz Bin Safeer Ahmad, Alvin Cheung
Leveraging Parallel Data Processing Frameworks with Verified Lifting
In Proceedings SYNT 2016, arXiv:1611.07178
EPTCS 229, 2016, pp. 67-83
10.4204/EPTCS.229.7
null
cs.PL cs.DB cs.DC
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Many parallel data frameworks have been proposed in recent years that let sequential programs access parallel processing. To capitalize on the benefits of such frameworks, existing code must often be rewritten to the domain-specific languages that each framework supports. This rewriting-tedious and error-prone-also requires developers to choose the framework that best optimizes performance given a specific workload. This paper describes Casper, a novel compiler that automatically retargets sequential Java code for execution on Hadoop, a parallel data processing framework that implements the MapReduce paradigm. Given a sequential code fragment, Casper uses verified lifting to infer a high-level summary expressed in our program specification language that is then compiled for execution on Hadoop. We demonstrate that Casper automatically translates Java benchmarks into Hadoop. The translated results execute on average 3.3x faster than the sequential implementations and scale better, as well, to larger datasets.
[ { "version": "v1", "created": "Wed, 23 Nov 2016 03:16:38 GMT" } ]
2016-11-24T00:00:00
[ [ "Ahmad", "Maaz Bin Safeer", "" ], [ "Cheung", "Alvin", "" ] ]
TITLE: Leveraging Parallel Data Processing Frameworks with Verified Lifting ABSTRACT: Many parallel data frameworks have been proposed in recent years that let sequential programs access parallel processing. To capitalize on the benefits of such frameworks, existing code must often be rewritten to the domain-specific languages that each framework supports. This rewriting-tedious and error-prone-also requires developers to choose the framework that best optimizes performance given a specific workload. This paper describes Casper, a novel compiler that automatically retargets sequential Java code for execution on Hadoop, a parallel data processing framework that implements the MapReduce paradigm. Given a sequential code fragment, Casper uses verified lifting to infer a high-level summary expressed in our program specification language that is then compiled for execution on Hadoop. We demonstrate that Casper automatically translates Java benchmarks into Hadoop. The translated results execute on average 3.3x faster than the sequential implementations and scale better, as well, to larger datasets.
no_new_dataset
0.944995
1611.07675
Ting Yao
Yingwei Pan, Ting Yao, Houqiang Li, Tao Mei
Video Captioning with Transferred Semantic Attributes
null
null
null
null
cs.CV
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Automatically generating natural language descriptions of videos plays a fundamental challenge for computer vision community. Most recent progress in this problem has been achieved through employing 2-D and/or 3-D Convolutional Neural Networks (CNN) to encode video content and Recurrent Neural Networks (RNN) to decode a sentence. In this paper, we present Long Short-Term Memory with Transferred Semantic Attributes (LSTM-TSA)---a novel deep architecture that incorporates the transferred semantic attributes learnt from images and videos into the CNN plus RNN framework, by training them in an end-to-end manner. The design of LSTM-TSA is highly inspired by the facts that 1) semantic attributes play a significant contribution to captioning, and 2) images and videos carry complementary semantics and thus can reinforce each other for captioning. To boost video captioning, we propose a novel transfer unit to model the mutually correlated attributes learnt from images and videos. Extensive experiments are conducted on three public datasets, i.e., MSVD, M-VAD and MPII-MD. Our proposed LSTM-TSA achieves to-date the best published performance in sentence generation on MSVD: 52.8% and 74.0% in terms of BLEU@4 and CIDEr-D. Superior results when compared to state-of-the-art methods are also reported on M-VAD and MPII-MD.
[ { "version": "v1", "created": "Wed, 23 Nov 2016 07:59:59 GMT" } ]
2016-11-24T00:00:00
[ [ "Pan", "Yingwei", "" ], [ "Yao", "Ting", "" ], [ "Li", "Houqiang", "" ], [ "Mei", "Tao", "" ] ]
TITLE: Video Captioning with Transferred Semantic Attributes ABSTRACT: Automatically generating natural language descriptions of videos plays a fundamental challenge for computer vision community. Most recent progress in this problem has been achieved through employing 2-D and/or 3-D Convolutional Neural Networks (CNN) to encode video content and Recurrent Neural Networks (RNN) to decode a sentence. In this paper, we present Long Short-Term Memory with Transferred Semantic Attributes (LSTM-TSA)---a novel deep architecture that incorporates the transferred semantic attributes learnt from images and videos into the CNN plus RNN framework, by training them in an end-to-end manner. The design of LSTM-TSA is highly inspired by the facts that 1) semantic attributes play a significant contribution to captioning, and 2) images and videos carry complementary semantics and thus can reinforce each other for captioning. To boost video captioning, we propose a novel transfer unit to model the mutually correlated attributes learnt from images and videos. Extensive experiments are conducted on three public datasets, i.e., MSVD, M-VAD and MPII-MD. Our proposed LSTM-TSA achieves to-date the best published performance in sentence generation on MSVD: 52.8% and 74.0% in terms of BLEU@4 and CIDEr-D. Superior results when compared to state-of-the-art methods are also reported on M-VAD and MPII-MD.
no_new_dataset
0.949902
1611.07743
Gil Keren
Gil Keren, Sivan Sabato, Bj\"orn Schuller
Tunable Sensitivity to Large Errors in Neural Network Training
The paper is accepted to the AAAI 2017 conference
null
null
null
stat.ML cs.LG cs.NE
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
When humans learn a new concept, they might ignore examples that they cannot make sense of at first, and only later focus on such examples, when they are more useful for learning. We propose incorporating this idea of tunable sensitivity for hard examples in neural network learning, using a new generalization of the cross-entropy gradient step, which can be used in place of the gradient in any gradient-based training method. The generalized gradient is parameterized by a value that controls the sensitivity of the training process to harder training examples. We tested our method on several benchmark datasets. We propose, and corroborate in our experiments, that the optimal level of sensitivity to hard example is positively correlated with the depth of the network. Moreover, the test prediction error obtained by our method is generally lower than that of the vanilla cross-entropy gradient learner. We therefore conclude that tunable sensitivity can be helpful for neural network learning.
[ { "version": "v1", "created": "Wed, 23 Nov 2016 11:14:01 GMT" } ]
2016-11-24T00:00:00
[ [ "Keren", "Gil", "" ], [ "Sabato", "Sivan", "" ], [ "Schuller", "Björn", "" ] ]
TITLE: Tunable Sensitivity to Large Errors in Neural Network Training ABSTRACT: When humans learn a new concept, they might ignore examples that they cannot make sense of at first, and only later focus on such examples, when they are more useful for learning. We propose incorporating this idea of tunable sensitivity for hard examples in neural network learning, using a new generalization of the cross-entropy gradient step, which can be used in place of the gradient in any gradient-based training method. The generalized gradient is parameterized by a value that controls the sensitivity of the training process to harder training examples. We tested our method on several benchmark datasets. We propose, and corroborate in our experiments, that the optimal level of sensitivity to hard example is positively correlated with the depth of the network. Moreover, the test prediction error obtained by our method is generally lower than that of the vanilla cross-entropy gradient learner. We therefore conclude that tunable sensitivity can be helpful for neural network learning.
no_new_dataset
0.951684
1611.07804
Nikita Astrakhantsev
N. Astrakhantsev
ATR4S: Toolkit with State-of-the-art Automatic Terms Recognition Methods in Scala
null
null
null
null
cs.CL
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Automatically recognized terminology is widely used for various domain-specific texts processing tasks, such as machine translation, information retrieval or sentiment analysis. However, there is still no agreement on which methods are best suited for particular settings and, moreover, there is no reliable comparison of already developed methods. We believe that one of the main reasons is the lack of state-of-the-art methods implementations, which are usually non-trivial to recreate. In order to address these issues, we present ATR4S, an open-source software written in Scala that comprises more than 15 methods for automatic terminology recognition (ATR) and implements the whole pipeline from text document preprocessing, to term candidates collection, term candidates scoring, and finally, term candidates ranking. It is highly scalable, modular and configurable tool with support of automatic caching. We also compare 10 state-of-the-art methods on 7 open datasets by average precision and processing time. Experimental comparison reveals that no single method demonstrates best average precision for all datasets and that other available tools for ATR do not contain the best methods.
[ { "version": "v1", "created": "Wed, 23 Nov 2016 14:14:52 GMT" } ]
2016-11-24T00:00:00
[ [ "Astrakhantsev", "N.", "" ] ]
TITLE: ATR4S: Toolkit with State-of-the-art Automatic Terms Recognition Methods in Scala ABSTRACT: Automatically recognized terminology is widely used for various domain-specific texts processing tasks, such as machine translation, information retrieval or sentiment analysis. However, there is still no agreement on which methods are best suited for particular settings and, moreover, there is no reliable comparison of already developed methods. We believe that one of the main reasons is the lack of state-of-the-art methods implementations, which are usually non-trivial to recreate. In order to address these issues, we present ATR4S, an open-source software written in Scala that comprises more than 15 methods for automatic terminology recognition (ATR) and implements the whole pipeline from text document preprocessing, to term candidates collection, term candidates scoring, and finally, term candidates ranking. It is highly scalable, modular and configurable tool with support of automatic caching. We also compare 10 state-of-the-art methods on 7 open datasets by average precision and processing time. Experimental comparison reveals that no single method demonstrates best average precision for all datasets and that other available tools for ATR do not contain the best methods.
no_new_dataset
0.933915
1510.00936
Ali Zarezade
Ali Zarezade, Ali Khodadadi, Mehrdad Farajtabar, Hamid R. Rabiee, Hongyuan Zha
Correlated Cascades: Compete or Cooperate
null
null
null
null
cs.SI
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
In real world social networks, there are multiple cascades which are rarely independent. They usually compete or cooperate with each other. Motivated by the reinforcement theory in sociology we leverage the fact that adoption of a user to any behavior is modeled by the aggregation of behaviors of its neighbors. We use a multidimensional marked Hawkes process to model users product adoption and consequently spread of cascades in social networks. The resulting inference problem is proved to be convex and is solved in parallel by using the barrier method. The advantage of the proposed model is twofold; it models correlated cascades and also learns the latent diffusion network. Experimental results on synthetic and two real datasets gathered from Twitter, URL shortening and music streaming services, illustrate the superior performance of the proposed model over the alternatives.
[ { "version": "v1", "created": "Sun, 4 Oct 2015 12:54:29 GMT" }, { "version": "v2", "created": "Wed, 18 Nov 2015 16:19:52 GMT" }, { "version": "v3", "created": "Tue, 22 Nov 2016 06:33:56 GMT" } ]
2016-11-23T00:00:00
[ [ "Zarezade", "Ali", "" ], [ "Khodadadi", "Ali", "" ], [ "Farajtabar", "Mehrdad", "" ], [ "Rabiee", "Hamid R.", "" ], [ "Zha", "Hongyuan", "" ] ]
TITLE: Correlated Cascades: Compete or Cooperate ABSTRACT: In real world social networks, there are multiple cascades which are rarely independent. They usually compete or cooperate with each other. Motivated by the reinforcement theory in sociology we leverage the fact that adoption of a user to any behavior is modeled by the aggregation of behaviors of its neighbors. We use a multidimensional marked Hawkes process to model users product adoption and consequently spread of cascades in social networks. The resulting inference problem is proved to be convex and is solved in parallel by using the barrier method. The advantage of the proposed model is twofold; it models correlated cascades and also learns the latent diffusion network. Experimental results on synthetic and two real datasets gathered from Twitter, URL shortening and music streaming services, illustrate the superior performance of the proposed model over the alternatives.
no_new_dataset
0.947478
1609.02372
Thomas Gastine
T. Gastine, J. Wicht, J. Aubert
Scaling regimes in spherical shell rotating convection
42 pages, 20 figures, 3 tables, accepted for publication in JFM
null
10.1017/jfm.2016.659
null
physics.flu-dyn astro-ph.EP astro-ph.SR physics.geo-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Rayleigh-B\'enard convection in rotating spherical shells can be considered as a simplified analogue of many astrophysical and geophysical fluid flows. Here, we use three-dimensional direct numerical simulations to study this physical process. We construct a dataset of more than 200 numerical models that cover a broad parameter range with Ekman numbers spanning $3\times 10^{-7} \leq E \leq 10^{-1}$, Rayleigh numbers within the range $10^3 < Ra < 2\times 10^{10}$ and a Prandtl number unity. We investigate the scaling behaviours of both local (length scales, boundary layers) and global (Nusselt and Reynolds numbers) properties across various physical regimes from onset of rotating convection to weakly-rotating convection. Close to critical, the convective flow is dominated by a triple force balance between viscosity, Coriolis force and buoyancy. For larger supercriticalities, a subset of our numerical data approaches the asymptotic diffusivity-free scaling of rotating convection $Nu\sim Ra^{3/2}E^{2}$ in a narrow fraction of the parameter space delimited by $6\,Ra_c \leq Ra \leq 0.4\,E^{-8/5}$. Using a decomposition of the viscous dissipation rate into bulk and boundary layer contributions, we establish a theoretical scaling of the flow velocity that accurately describes the numerical data. In rapidly-rotating turbulent convection, the fluid bulk is controlled by a triple force balance between Coriolis, inertia and buoyancy, while the remaining fraction of the dissipation can be attributed to the viscous friction in the Ekman layers. Beyond $Ra \simeq E^{-8/5}$, the rotational constraint on the convective flow is gradually lost and the flow properties vary to match the regime changes between rotation-dominated and non-rotating convection. The quantity $Ra E^{12/7}$ provides an accurate transition parameter to separate rotating and non-rotating convection.
[ { "version": "v1", "created": "Thu, 8 Sep 2016 10:46:27 GMT" }, { "version": "v2", "created": "Thu, 6 Oct 2016 12:40:32 GMT" } ]
2016-11-23T00:00:00
[ [ "Gastine", "T.", "" ], [ "Wicht", "J.", "" ], [ "Aubert", "J.", "" ] ]
TITLE: Scaling regimes in spherical shell rotating convection ABSTRACT: Rayleigh-B\'enard convection in rotating spherical shells can be considered as a simplified analogue of many astrophysical and geophysical fluid flows. Here, we use three-dimensional direct numerical simulations to study this physical process. We construct a dataset of more than 200 numerical models that cover a broad parameter range with Ekman numbers spanning $3\times 10^{-7} \leq E \leq 10^{-1}$, Rayleigh numbers within the range $10^3 < Ra < 2\times 10^{10}$ and a Prandtl number unity. We investigate the scaling behaviours of both local (length scales, boundary layers) and global (Nusselt and Reynolds numbers) properties across various physical regimes from onset of rotating convection to weakly-rotating convection. Close to critical, the convective flow is dominated by a triple force balance between viscosity, Coriolis force and buoyancy. For larger supercriticalities, a subset of our numerical data approaches the asymptotic diffusivity-free scaling of rotating convection $Nu\sim Ra^{3/2}E^{2}$ in a narrow fraction of the parameter space delimited by $6\,Ra_c \leq Ra \leq 0.4\,E^{-8/5}$. Using a decomposition of the viscous dissipation rate into bulk and boundary layer contributions, we establish a theoretical scaling of the flow velocity that accurately describes the numerical data. In rapidly-rotating turbulent convection, the fluid bulk is controlled by a triple force balance between Coriolis, inertia and buoyancy, while the remaining fraction of the dissipation can be attributed to the viscous friction in the Ekman layers. Beyond $Ra \simeq E^{-8/5}$, the rotational constraint on the convective flow is gradually lost and the flow properties vary to match the regime changes between rotation-dominated and non-rotating convection. The quantity $Ra E^{12/7}$ provides an accurate transition parameter to separate rotating and non-rotating convection.
no_new_dataset
0.942718
1611.04326
Aditya Joshi
Aditya Joshi, Prayas Jain, Pushpak Bhattacharyya, Mark Carman
`Who would have thought of that!': A Hierarchical Topic Model for Extraction of Sarcasm-prevalent Topics and Sarcasm Detection
This version of the paper contains corrected changes, after the camera -ready submission. These changes were observed based on an issue in the output returned by SVM Perf. This paper will be presented at ExPROM workshop at COLING 2016
null
null
null
cs.CL
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Topic Models have been reported to be beneficial for aspect-based sentiment analysis. This paper reports a simple topic model for sarcasm detection, a first, to the best of our knowledge. Designed on the basis of the intuition that sarcastic tweets are likely to have a mixture of words of both sentiments as against tweets with literal sentiment (either positive or negative), our hierarchical topic model discovers sarcasm-prevalent topics and topic-level sentiment. Using a dataset of tweets labeled using hashtags, the model estimates topic-level, and sentiment-level distributions. Our evaluation shows that topics such as `work', `gun laws', `weather' are sarcasm-prevalent topics. Our model is also able to discover the mixture of sentiment-bearing words that exist in a text of a given sentiment-related label. Finally, we apply our model to predict sarcasm in tweets. We outperform two prior work based on statistical classifiers with specific features, by around 25\%.
[ { "version": "v1", "created": "Mon, 14 Nov 2016 10:40:44 GMT" }, { "version": "v2", "created": "Tue, 22 Nov 2016 10:55:56 GMT" } ]
2016-11-23T00:00:00
[ [ "Joshi", "Aditya", "" ], [ "Jain", "Prayas", "" ], [ "Bhattacharyya", "Pushpak", "" ], [ "Carman", "Mark", "" ] ]
TITLE: `Who would have thought of that!': A Hierarchical Topic Model for Extraction of Sarcasm-prevalent Topics and Sarcasm Detection ABSTRACT: Topic Models have been reported to be beneficial for aspect-based sentiment analysis. This paper reports a simple topic model for sarcasm detection, a first, to the best of our knowledge. Designed on the basis of the intuition that sarcastic tweets are likely to have a mixture of words of both sentiments as against tweets with literal sentiment (either positive or negative), our hierarchical topic model discovers sarcasm-prevalent topics and topic-level sentiment. Using a dataset of tweets labeled using hashtags, the model estimates topic-level, and sentiment-level distributions. Our evaluation shows that topics such as `work', `gun laws', `weather' are sarcasm-prevalent topics. Our model is also able to discover the mixture of sentiment-bearing words that exist in a text of a given sentiment-related label. Finally, we apply our model to predict sarcasm in tweets. We outperform two prior work based on statistical classifiers with specific features, by around 25\%.
no_new_dataset
0.948298
1611.05244
Mengyue Geng
Mengyue Geng and Yaowei Wang and Tao Xiang and Yonghong Tian
Deep Transfer Learning for Person Re-identification
12 pages, 2 figures
null
null
null
cs.CV
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Person re-identification (Re-ID) poses a unique challenge to deep learning: how to learn a deep model with millions of parameters on a small training set of few or no labels. In this paper, a number of deep transfer learning models are proposed to address the data sparsity problem. First, a deep network architecture is designed which differs from existing deep Re-ID models in that (a) it is more suitable for transferring representations learned from large image classification datasets, and (b) classification loss and verification loss are combined, each of which adopts a different dropout strategy. Second, a two-stepped fine-tuning strategy is developed to transfer knowledge from auxiliary datasets. Third, given an unlabelled Re-ID dataset, a novel unsupervised deep transfer learning model is developed based on co-training. The proposed models outperform the state-of-the-art deep Re-ID models by large margins: we achieve Rank-1 accuracy of 85.4\%, 83.7\% and 56.3\% on CUHK03, Market1501, and VIPeR respectively, whilst on VIPeR, our unsupervised model (45.1\%) beats most supervised models.
[ { "version": "v1", "created": "Wed, 16 Nov 2016 12:14:09 GMT" }, { "version": "v2", "created": "Tue, 22 Nov 2016 12:16:51 GMT" } ]
2016-11-23T00:00:00
[ [ "Geng", "Mengyue", "" ], [ "Wang", "Yaowei", "" ], [ "Xiang", "Tao", "" ], [ "Tian", "Yonghong", "" ] ]
TITLE: Deep Transfer Learning for Person Re-identification ABSTRACT: Person re-identification (Re-ID) poses a unique challenge to deep learning: how to learn a deep model with millions of parameters on a small training set of few or no labels. In this paper, a number of deep transfer learning models are proposed to address the data sparsity problem. First, a deep network architecture is designed which differs from existing deep Re-ID models in that (a) it is more suitable for transferring representations learned from large image classification datasets, and (b) classification loss and verification loss are combined, each of which adopts a different dropout strategy. Second, a two-stepped fine-tuning strategy is developed to transfer knowledge from auxiliary datasets. Third, given an unlabelled Re-ID dataset, a novel unsupervised deep transfer learning model is developed based on co-training. The proposed models outperform the state-of-the-art deep Re-ID models by large margins: we achieve Rank-1 accuracy of 85.4\%, 83.7\% and 56.3\% on CUHK03, Market1501, and VIPeR respectively, whilst on VIPeR, our unsupervised model (45.1\%) beats most supervised models.
no_new_dataset
0.952042
1611.07054
Sebastian P\"olsterl
Sebastian P\"olsterl, Nassir Navab, Amin Katouzian
An Efficient Training Algorithm for Kernel Survival Support Vector Machines
ECML PKDD MLLS 2016: 3rd Workshop on Machine Learning in Life Sciences
null
null
null
cs.LG cs.AI stat.ML
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Survival analysis is a fundamental tool in medical research to identify predictors of adverse events and develop systems for clinical decision support. In order to leverage large amounts of patient data, efficient optimisation routines are paramount. We propose an efficient training algorithm for the kernel survival support vector machine (SSVM). We directly optimise the primal objective function and employ truncated Newton optimisation and order statistic trees to significantly lower computational costs compared to previous training algorithms, which require $O(n^4)$ space and $O(p n^6)$ time for datasets with $n$ samples and $p$ features. Our results demonstrate that our proposed optimisation scheme allows analysing data of a much larger scale with no loss in prediction performance. Experiments on synthetic and 5 real-world datasets show that our technique outperforms existing kernel SSVM formulations if the amount of right censoring is high ($\geq85\%$), and performs comparably otherwise.
[ { "version": "v1", "created": "Mon, 21 Nov 2016 21:09:33 GMT" } ]
2016-11-23T00:00:00
[ [ "Pölsterl", "Sebastian", "" ], [ "Navab", "Nassir", "" ], [ "Katouzian", "Amin", "" ] ]
TITLE: An Efficient Training Algorithm for Kernel Survival Support Vector Machines ABSTRACT: Survival analysis is a fundamental tool in medical research to identify predictors of adverse events and develop systems for clinical decision support. In order to leverage large amounts of patient data, efficient optimisation routines are paramount. We propose an efficient training algorithm for the kernel survival support vector machine (SSVM). We directly optimise the primal objective function and employ truncated Newton optimisation and order statistic trees to significantly lower computational costs compared to previous training algorithms, which require $O(n^4)$ space and $O(p n^6)$ time for datasets with $n$ samples and $p$ features. Our results demonstrate that our proposed optimisation scheme allows analysing data of a much larger scale with no loss in prediction performance. Experiments on synthetic and 5 real-world datasets show that our technique outperforms existing kernel SSVM formulations if the amount of right censoring is high ($\geq85\%$), and performs comparably otherwise.
no_new_dataset
0.949012
1611.07119
Chongxuan Li
Chongxuan Li and Jun Zhu and Bo Zhang
Max-Margin Deep Generative Models for (Semi-)Supervised Learning
arXiv admin note: substantial text overlap with arXiv:1504.06787
null
null
null
cs.CV cs.LG stat.ML
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Deep generative models (DGMs) are effective on learning multilayered representations of complex data and performing inference of input data by exploring the generative ability. However, it is relatively insufficient to empower the discriminative ability of DGMs on making accurate predictions. This paper presents max-margin deep generative models (mmDGMs) and a class-conditional variant (mmDCGMs), which explore the strongly discriminative principle of max-margin learning to improve the predictive performance of DGMs in both supervised and semi-supervised learning, while retaining the generative capability. In semi-supervised learning, we use the predictions of a max-margin classifier as the missing labels instead of performing full posterior inference for efficiency; we also introduce additional max-margin and label-balance regularization terms of unlabeled data for effectiveness. We develop an efficient doubly stochastic subgradient algorithm for the piecewise linear objectives in different settings. Empirical results on various datasets demonstrate that: (1) max-margin learning can significantly improve the prediction performance of DGMs and meanwhile retain the generative ability; (2) in supervised learning, mmDGMs are competitive to the best fully discriminative networks when employing convolutional neural networks as the generative and recognition models; and (3) in semi-supervised learning, mmDCGMs can perform efficient inference and achieve state-of-the-art classification results on several benchmarks.
[ { "version": "v1", "created": "Tue, 22 Nov 2016 01:36:29 GMT" } ]
2016-11-23T00:00:00
[ [ "Li", "Chongxuan", "" ], [ "Zhu", "Jun", "" ], [ "Zhang", "Bo", "" ] ]
TITLE: Max-Margin Deep Generative Models for (Semi-)Supervised Learning ABSTRACT: Deep generative models (DGMs) are effective on learning multilayered representations of complex data and performing inference of input data by exploring the generative ability. However, it is relatively insufficient to empower the discriminative ability of DGMs on making accurate predictions. This paper presents max-margin deep generative models (mmDGMs) and a class-conditional variant (mmDCGMs), which explore the strongly discriminative principle of max-margin learning to improve the predictive performance of DGMs in both supervised and semi-supervised learning, while retaining the generative capability. In semi-supervised learning, we use the predictions of a max-margin classifier as the missing labels instead of performing full posterior inference for efficiency; we also introduce additional max-margin and label-balance regularization terms of unlabeled data for effectiveness. We develop an efficient doubly stochastic subgradient algorithm for the piecewise linear objectives in different settings. Empirical results on various datasets demonstrate that: (1) max-margin learning can significantly improve the prediction performance of DGMs and meanwhile retain the generative ability; (2) in supervised learning, mmDGMs are competitive to the best fully discriminative networks when employing convolutional neural networks as the generative and recognition models; and (3) in semi-supervised learning, mmDCGMs can perform efficient inference and achieve state-of-the-art classification results on several benchmarks.
no_new_dataset
0.948822
1611.07212
Albert Haque
Albert Haque, Alexandre Alahi, Li Fei-Fei
Recurrent Attention Models for Depth-Based Person Identification
Computer Vision and Pattern Recognition (CVPR) 2016
null
null
null
cs.CV
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We present an attention-based model that reasons on human body shape and motion dynamics to identify individuals in the absence of RGB information, hence in the dark. Our approach leverages unique 4D spatio-temporal signatures to address the identification problem across days. Formulated as a reinforcement learning task, our model is based on a combination of convolutional and recurrent neural networks with the goal of identifying small, discriminative regions indicative of human identity. We demonstrate that our model produces state-of-the-art results on several published datasets given only depth images. We further study the robustness of our model towards viewpoint, appearance, and volumetric changes. Finally, we share insights gleaned from interpretable 2D, 3D, and 4D visualizations of our model's spatio-temporal attention.
[ { "version": "v1", "created": "Tue, 22 Nov 2016 09:27:30 GMT" } ]
2016-11-23T00:00:00
[ [ "Haque", "Albert", "" ], [ "Alahi", "Alexandre", "" ], [ "Fei-Fei", "Li", "" ] ]
TITLE: Recurrent Attention Models for Depth-Based Person Identification ABSTRACT: We present an attention-based model that reasons on human body shape and motion dynamics to identify individuals in the absence of RGB information, hence in the dark. Our approach leverages unique 4D spatio-temporal signatures to address the identification problem across days. Formulated as a reinforcement learning task, our model is based on a combination of convolutional and recurrent neural networks with the goal of identifying small, discriminative regions indicative of human identity. We demonstrate that our model produces state-of-the-art results on several published datasets given only depth images. We further study the robustness of our model towards viewpoint, appearance, and volumetric changes. Finally, we share insights gleaned from interpretable 2D, 3D, and 4D visualizations of our model's spatio-temporal attention.
no_new_dataset
0.948346
1611.07308
Thomas Kipf
Thomas N. Kipf, Max Welling
Variational Graph Auto-Encoders
Bayesian Deep Learning Workshop (NIPS 2016)
null
null
null
stat.ML cs.LG
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We introduce the variational graph auto-encoder (VGAE), a framework for unsupervised learning on graph-structured data based on the variational auto-encoder (VAE). This model makes use of latent variables and is capable of learning interpretable latent representations for undirected graphs. We demonstrate this model using a graph convolutional network (GCN) encoder and a simple inner product decoder. Our model achieves competitive results on a link prediction task in citation networks. In contrast to most existing models for unsupervised learning on graph-structured data and link prediction, our model can naturally incorporate node features, which significantly improves predictive performance on a number of benchmark datasets.
[ { "version": "v1", "created": "Mon, 21 Nov 2016 11:37:17 GMT" } ]
2016-11-23T00:00:00
[ [ "Kipf", "Thomas N.", "" ], [ "Welling", "Max", "" ] ]
TITLE: Variational Graph Auto-Encoders ABSTRACT: We introduce the variational graph auto-encoder (VGAE), a framework for unsupervised learning on graph-structured data based on the variational auto-encoder (VAE). This model makes use of latent variables and is capable of learning interpretable latent representations for undirected graphs. We demonstrate this model using a graph convolutional network (GCN) encoder and a simple inner product decoder. Our model achieves competitive results on a link prediction task in citation networks. In contrast to most existing models for unsupervised learning on graph-structured data and link prediction, our model can naturally incorporate node features, which significantly improves predictive performance on a number of benchmark datasets.
no_new_dataset
0.94699
1611.07385
Xiao Yang
Xiao Yang, Dafang He, Wenyi Huang, Zihan Zhou, Alex Ororbia, Dan Kifer, C. Lee Giles
Smart Library: Identifying Books in a Library using Richly Supervised Deep Scene Text Reading
null
null
null
null
cs.CV
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Physical library collections are valuable and long standing resources for knowledge and learning. However, managing books in a large bookshelf and finding books on it often leads to tedious manual work, especially for large book collections where books might be missing or misplaced. Recently, deep neural models, such as Convolutional Neural Networks (CNN) and Recurrent Neural Networks (RNN) have achieved great success for scene text detection and recognition. Motivated by these recent successes, we aim to investigate their viability in facilitating book management, a task that introduces further challenges including large amounts of cluttered scene text, distortion, and varied lighting conditions. In this paper, we present a library inventory building and retrieval system based on scene text reading methods. We specifically design our scene text recognition model using rich supervision to accelerate training and achieve state-of-the-art performance on several benchmark datasets. Our proposed system has the potential to greatly reduce the amount of human labor required in managing book inventories as well as the space needed to store book information.
[ { "version": "v1", "created": "Tue, 22 Nov 2016 16:12:03 GMT" } ]
2016-11-23T00:00:00
[ [ "Yang", "Xiao", "" ], [ "He", "Dafang", "" ], [ "Huang", "Wenyi", "" ], [ "Zhou", "Zihan", "" ], [ "Ororbia", "Alex", "" ], [ "Kifer", "Dan", "" ], [ "Giles", "C. Lee", "" ] ]
TITLE: Smart Library: Identifying Books in a Library using Richly Supervised Deep Scene Text Reading ABSTRACT: Physical library collections are valuable and long standing resources for knowledge and learning. However, managing books in a large bookshelf and finding books on it often leads to tedious manual work, especially for large book collections where books might be missing or misplaced. Recently, deep neural models, such as Convolutional Neural Networks (CNN) and Recurrent Neural Networks (RNN) have achieved great success for scene text detection and recognition. Motivated by these recent successes, we aim to investigate their viability in facilitating book management, a task that introduces further challenges including large amounts of cluttered scene text, distortion, and varied lighting conditions. In this paper, we present a library inventory building and retrieval system based on scene text reading methods. We specifically design our scene text recognition model using rich supervision to accelerate training and achieve state-of-the-art performance on several benchmark datasets. Our proposed system has the potential to greatly reduce the amount of human labor required in managing book inventories as well as the space needed to store book information.
no_new_dataset
0.948202
1611.07438
Lu Zhang
Lu Zhang (1), Yongkai Wu (1), Xintao Wu (1) ((1) University of Arkansas)
Achieving non-discrimination in data release
null
null
null
null
cs.LG
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Discrimination discovery and prevention/removal are increasingly important tasks in data mining. Discrimination discovery aims to unveil discriminatory practices on the protected attribute (e.g., gender) by analyzing the dataset of historical decision records, and discrimination prevention aims to remove discrimination by modifying the biased data before conducting predictive analysis. In this paper, we show that the key to discrimination discovery and prevention is to find the meaningful partitions that can be used to provide quantitative evidences for the judgment of discrimination. With the support of the causal graph, we present a graphical condition for identifying a meaningful partition. Based on that, we develop a simple criterion for the claim of non-discrimination, and propose discrimination removal algorithms which accurately remove discrimination while retaining good data utility. Experiments using real datasets show the effectiveness of our approaches.
[ { "version": "v1", "created": "Tue, 22 Nov 2016 17:55:28 GMT" } ]
2016-11-23T00:00:00
[ [ "Zhang", "Lu", "" ], [ "Wu", "Yongkai", "" ], [ "Wu", "Xintao", "" ] ]
TITLE: Achieving non-discrimination in data release ABSTRACT: Discrimination discovery and prevention/removal are increasingly important tasks in data mining. Discrimination discovery aims to unveil discriminatory practices on the protected attribute (e.g., gender) by analyzing the dataset of historical decision records, and discrimination prevention aims to remove discrimination by modifying the biased data before conducting predictive analysis. In this paper, we show that the key to discrimination discovery and prevention is to find the meaningful partitions that can be used to provide quantitative evidences for the judgment of discrimination. With the support of the causal graph, we present a graphical condition for identifying a meaningful partition. Based on that, we develop a simple criterion for the claim of non-discrimination, and propose discrimination removal algorithms which accurately remove discrimination while retaining good data utility. Experiments using real datasets show the effectiveness of our approaches.
no_new_dataset
0.950869
1611.07509
Lu Zhang
Lu Zhang (1), Yongkai Wu (1), Xintao Wu (1) ((1) University of Arkansas)
A causal framework for discovering and removing direct and indirect discrimination
null
null
null
null
cs.LG
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Anti-discrimination is an increasingly important task in data science. In this paper, we investigate the problem of discovering both direct and indirect discrimination from the historical data, and removing the discriminatory effects before the data is used for predictive analysis (e.g., building classifiers). We make use of the causal network to capture the causal structure of the data. Then we model direct and indirect discrimination as the path-specific effects, which explicitly distinguish the two types of discrimination as the causal effects transmitted along different paths in the network. Based on that, we propose an effective algorithm for discovering direct and indirect discrimination, as well as an algorithm for precisely removing both types of discrimination while retaining good data utility. Different from previous works, our approaches can ensure that the predictive models built from the modified data will not incur discrimination in decision making. Experiments using real datasets show the effectiveness of our approaches.
[ { "version": "v1", "created": "Tue, 22 Nov 2016 20:50:47 GMT" } ]
2016-11-23T00:00:00
[ [ "Zhang", "Lu", "" ], [ "Wu", "Yongkai", "" ], [ "Wu", "Xintao", "" ] ]
TITLE: A causal framework for discovering and removing direct and indirect discrimination ABSTRACT: Anti-discrimination is an increasingly important task in data science. In this paper, we investigate the problem of discovering both direct and indirect discrimination from the historical data, and removing the discriminatory effects before the data is used for predictive analysis (e.g., building classifiers). We make use of the causal network to capture the causal structure of the data. Then we model direct and indirect discrimination as the path-specific effects, which explicitly distinguish the two types of discrimination as the causal effects transmitted along different paths in the network. Based on that, we propose an effective algorithm for discovering direct and indirect discrimination, as well as an algorithm for precisely removing both types of discrimination while retaining good data utility. Different from previous works, our approaches can ensure that the predictive models built from the modified data will not incur discrimination in decision making. Experiments using real datasets show the effectiveness of our approaches.
no_new_dataset
0.950411
1411.5417
Abhradeep Guha Thakurta
Kunal Talwar, Abhradeep Thakurta, Li Zhang
Private Empirical Risk Minimization Beyond the Worst Case: The Effect of the Constraint Set Geometry
null
null
null
null
cs.LG cs.CR stat.ML
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Empirical Risk Minimization (ERM) is a standard technique in machine learning, where a model is selected by minimizing a loss function over constraint set. When the training dataset consists of private information, it is natural to use a differentially private ERM algorithm, and this problem has been the subject of a long line of work started with Chaudhuri and Monteleoni 2008. A private ERM algorithm outputs an approximate minimizer of the loss function and its error can be measured as the difference from the optimal value of the loss function. When the constraint set is arbitrary, the required error bounds are fairly well understood \cite{BassilyST14}. In this work, we show that the geometric properties of the constraint set can be used to derive significantly better results. Specifically, we show that a differentially private version of Mirror Descent leads to error bounds of the form $\tilde{O}(G_{\mathcal{C}}/n)$ for a lipschitz loss function, improving on the $\tilde{O}(\sqrt{p}/n)$ bounds in Bassily, Smith and Thakurta 2014. Here $p$ is the dimensionality of the problem, $n$ is the number of data points in the training set, and $G_{\mathcal{C}}$ denotes the Gaussian width of the constraint set that we optimize over. We show similar improvements for strongly convex functions, and for smooth functions. In addition, we show that when the loss function is Lipschitz with respect to the $\ell_1$ norm and $\mathcal{C}$ is $\ell_1$-bounded, a differentially private version of the Frank-Wolfe algorithm gives error bounds of the form $\tilde{O}(n^{-2/3})$. This captures the important and common case of sparse linear regression (LASSO), when the data $x_i$ satisfies $|x_i|_{\infty} \leq 1$ and we optimize over the $\ell_1$ ball. We show new lower bounds for this setting, that together with known bounds, imply that all our upper bounds are tight.
[ { "version": "v1", "created": "Thu, 20 Nov 2014 01:33:53 GMT" }, { "version": "v2", "created": "Thu, 5 Mar 2015 02:38:52 GMT" }, { "version": "v3", "created": "Sun, 20 Nov 2016 22:40:46 GMT" } ]
2016-11-22T00:00:00
[ [ "Talwar", "Kunal", "" ], [ "Thakurta", "Abhradeep", "" ], [ "Zhang", "Li", "" ] ]
TITLE: Private Empirical Risk Minimization Beyond the Worst Case: The Effect of the Constraint Set Geometry ABSTRACT: Empirical Risk Minimization (ERM) is a standard technique in machine learning, where a model is selected by minimizing a loss function over constraint set. When the training dataset consists of private information, it is natural to use a differentially private ERM algorithm, and this problem has been the subject of a long line of work started with Chaudhuri and Monteleoni 2008. A private ERM algorithm outputs an approximate minimizer of the loss function and its error can be measured as the difference from the optimal value of the loss function. When the constraint set is arbitrary, the required error bounds are fairly well understood \cite{BassilyST14}. In this work, we show that the geometric properties of the constraint set can be used to derive significantly better results. Specifically, we show that a differentially private version of Mirror Descent leads to error bounds of the form $\tilde{O}(G_{\mathcal{C}}/n)$ for a lipschitz loss function, improving on the $\tilde{O}(\sqrt{p}/n)$ bounds in Bassily, Smith and Thakurta 2014. Here $p$ is the dimensionality of the problem, $n$ is the number of data points in the training set, and $G_{\mathcal{C}}$ denotes the Gaussian width of the constraint set that we optimize over. We show similar improvements for strongly convex functions, and for smooth functions. In addition, we show that when the loss function is Lipschitz with respect to the $\ell_1$ norm and $\mathcal{C}$ is $\ell_1$-bounded, a differentially private version of the Frank-Wolfe algorithm gives error bounds of the form $\tilde{O}(n^{-2/3})$. This captures the important and common case of sparse linear regression (LASSO), when the data $x_i$ satisfies $|x_i|_{\infty} \leq 1$ and we optimize over the $\ell_1$ ball. We show new lower bounds for this setting, that together with known bounds, imply that all our upper bounds are tight.
no_new_dataset
0.949902
1509.01520
Radu Horaud P
Sileye Ba, Xavier Alameda-Pineda, Alessio Xompero and Radu Horaud
An On-line Variational Bayesian Model for Multi-Person Tracking from Cluttered Scenes
21 pages, 9 figures, 4 tables
Computer Vision and Image Understanding, volume 153, December 2016, pages 64-76
10.1016/j.cviu.2016.07.006
null
cs.CV stat.ML
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Object tracking is an ubiquitous problem that appears in many applications such as remote sensing, audio processing, computer vision, human-machine interfaces, human-robot interaction, etc. Although thoroughly investigated in computer vision, tracking a time-varying number of persons remains a challenging open problem. In this paper, we propose an on-line variational Bayesian model for multi-person tracking from cluttered visual observations provided by person detectors. The contributions of this paper are the followings. First, we propose a variational Bayesian framework for tracking an unknown and varying number of persons. Second, our model results in a variational expectation-maximization (VEM) algorithm with closed-form expressions for the posterior distributions of the latent variables and for the estimation of the model parameters. Third, the proposed model exploits observations from multiple detectors, and it is therefore multimodal by nature. Finally, we propose to embed both object-birth and object-visibility processes in an effort to robustly handle person appearances and disappearances over time. Evaluated on classical multiple person tracking datasets, our method shows competitive results with respect to state-of-the-art multiple-object tracking models, such as the probability hypothesis density (PHD) filter among others.
[ { "version": "v1", "created": "Fri, 4 Sep 2015 16:16:42 GMT" }, { "version": "v2", "created": "Thu, 31 Mar 2016 13:06:59 GMT" }, { "version": "v3", "created": "Thu, 30 Jun 2016 08:50:42 GMT" } ]
2016-11-22T00:00:00
[ [ "Ba", "Sileye", "" ], [ "Alameda-Pineda", "Xavier", "" ], [ "Xompero", "Alessio", "" ], [ "Horaud", "Radu", "" ] ]
TITLE: An On-line Variational Bayesian Model for Multi-Person Tracking from Cluttered Scenes ABSTRACT: Object tracking is an ubiquitous problem that appears in many applications such as remote sensing, audio processing, computer vision, human-machine interfaces, human-robot interaction, etc. Although thoroughly investigated in computer vision, tracking a time-varying number of persons remains a challenging open problem. In this paper, we propose an on-line variational Bayesian model for multi-person tracking from cluttered visual observations provided by person detectors. The contributions of this paper are the followings. First, we propose a variational Bayesian framework for tracking an unknown and varying number of persons. Second, our model results in a variational expectation-maximization (VEM) algorithm with closed-form expressions for the posterior distributions of the latent variables and for the estimation of the model parameters. Third, the proposed model exploits observations from multiple detectors, and it is therefore multimodal by nature. Finally, we propose to embed both object-birth and object-visibility processes in an effort to robustly handle person appearances and disappearances over time. Evaluated on classical multiple person tracking datasets, our method shows competitive results with respect to state-of-the-art multiple-object tracking models, such as the probability hypothesis density (PHD) filter among others.
no_new_dataset
0.949995
1604.03058
Xundong Wu
Xundong Wu, Yong Wu and Yong Zhao
Binarized Neural Networks on the ImageNet Classification Task
null
null
null
null
cs.CV cs.LG cs.NE
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We trained Binarized Neural Networks (BNNs) on the high resolution ImageNet ILSVRC-2102 dataset classification task and achieved a good performance. With a moderate size network of 13 layers, we obtained top-5 classification accuracy rate of 84.1 % on validation set through network distillation, much better than previous published results of 73.2% on XNOR network and 69.1% on binarized GoogleNET. We expect networks of better performance can be obtained by following our current strategies. We provide a detailed discussion and preliminary analysis on strategies used in the network training.
[ { "version": "v1", "created": "Mon, 11 Apr 2016 18:39:33 GMT" }, { "version": "v2", "created": "Wed, 13 Apr 2016 03:22:37 GMT" }, { "version": "v3", "created": "Mon, 24 Oct 2016 15:25:06 GMT" }, { "version": "v4", "created": "Tue, 8 Nov 2016 00:38:03 GMT" }, { "version": "v5", "created": "Sat, 19 Nov 2016 01:37:40 GMT" } ]
2016-11-22T00:00:00
[ [ "Wu", "Xundong", "" ], [ "Wu", "Yong", "" ], [ "Zhao", "Yong", "" ] ]
TITLE: Binarized Neural Networks on the ImageNet Classification Task ABSTRACT: We trained Binarized Neural Networks (BNNs) on the high resolution ImageNet ILSVRC-2102 dataset classification task and achieved a good performance. With a moderate size network of 13 layers, we obtained top-5 classification accuracy rate of 84.1 % on validation set through network distillation, much better than previous published results of 73.2% on XNOR network and 69.1% on binarized GoogleNET. We expect networks of better performance can be obtained by following our current strategies. We provide a detailed discussion and preliminary analysis on strategies used in the network training.
no_new_dataset
0.958577
1606.03568
Mikael K{\aa}geb\"ack
Mikael K{\aa}geb\"ack, Hans Salomonsson
Word Sense Disambiguation using a Bidirectional LSTM
null
null
null
null
cs.CL cs.AI
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
In this paper we present a clean, yet effective, model for word sense disambiguation. Our approach leverage a bidirectional long short-term memory network which is shared between all words. This enables the model to share statistical strength and to scale well with vocabulary size. The model is trained end-to-end, directly from the raw text to sense labels, and makes effective use of word order. We evaluate our approach on two standard datasets, using identical hyperparameter settings, which are in turn tuned on a third set of held out data. We employ no external resources (e.g. knowledge graphs, part-of-speech tagging, etc), language specific features, or hand crafted rules, but still achieve statistically equivalent results to the best state-of-the-art systems, that employ no such limitations.
[ { "version": "v1", "created": "Sat, 11 Jun 2016 08:12:02 GMT" }, { "version": "v2", "created": "Fri, 18 Nov 2016 22:47:07 GMT" } ]
2016-11-22T00:00:00
[ [ "Kågebäck", "Mikael", "" ], [ "Salomonsson", "Hans", "" ] ]
TITLE: Word Sense Disambiguation using a Bidirectional LSTM ABSTRACT: In this paper we present a clean, yet effective, model for word sense disambiguation. Our approach leverage a bidirectional long short-term memory network which is shared between all words. This enables the model to share statistical strength and to scale well with vocabulary size. The model is trained end-to-end, directly from the raw text to sense labels, and makes effective use of word order. We evaluate our approach on two standard datasets, using identical hyperparameter settings, which are in turn tuned on a third set of held out data. We employ no external resources (e.g. knowledge graphs, part-of-speech tagging, etc), language specific features, or hand crafted rules, but still achieve statistically equivalent results to the best state-of-the-art systems, that employ no such limitations.
no_new_dataset
0.952926
1606.04327
Pawel Foremski
Pawel Foremski, David Plonka, Arthur Berger
Entropy/IP: Uncovering Structure in IPv6 Addresses
Paper presented at the ACM IMC 2016 in Santa Monica, USA (https://dl.acm.org/citation.cfm?id=2987445). Live Demo site available at http://www.entropy-ip.com/
IMC '16 Proceedings of the 2016 ACM on Internet Measurement Conference, pp. 167-181
10.1145/2987443.2987445
null
cs.NI cs.AI cs.IT math.IT
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
In this paper, we introduce Entropy/IP: a system that discovers Internet address structure based on analyses of a subset of IPv6 addresses known to be active, i.e., training data, gleaned by readily available passive and active means. The system is completely automated and employs a combination of information-theoretic and machine learning techniques to probabilistically model IPv6 addresses. We present results showing that our system is effective in exposing structural characteristics of portions of the IPv6 Internet address space populated by active client, service, and router addresses. In addition to visualizing the address structure for exploration, the system uses its models to generate candidate target addresses for scanning. For each of 15 evaluated datasets, we train on 1K addresses and generate 1M candidates for scanning. We achieve some success in 14 datasets, finding up to 40% of the generated addresses to be active. In 11 of these datasets, we find active network identifiers (e.g., /64 prefixes or `subnets') not seen in training. Thus, we provide the first evidence that it is practical to discover subnets and hosts by scanning probabilistically selected areas of the IPv6 address space not known to contain active hosts a priori.
[ { "version": "v1", "created": "Tue, 14 Jun 2016 12:38:26 GMT" }, { "version": "v2", "created": "Mon, 21 Nov 2016 12:43:00 GMT" } ]
2016-11-22T00:00:00
[ [ "Foremski", "Pawel", "" ], [ "Plonka", "David", "" ], [ "Berger", "Arthur", "" ] ]
TITLE: Entropy/IP: Uncovering Structure in IPv6 Addresses ABSTRACT: In this paper, we introduce Entropy/IP: a system that discovers Internet address structure based on analyses of a subset of IPv6 addresses known to be active, i.e., training data, gleaned by readily available passive and active means. The system is completely automated and employs a combination of information-theoretic and machine learning techniques to probabilistically model IPv6 addresses. We present results showing that our system is effective in exposing structural characteristics of portions of the IPv6 Internet address space populated by active client, service, and router addresses. In addition to visualizing the address structure for exploration, the system uses its models to generate candidate target addresses for scanning. For each of 15 evaluated datasets, we train on 1K addresses and generate 1M candidates for scanning. We achieve some success in 14 datasets, finding up to 40% of the generated addresses to be active. In 11 of these datasets, we find active network identifiers (e.g., /64 prefixes or `subnets') not seen in training. Thus, we provide the first evidence that it is practical to discover subnets and hosts by scanning probabilistically selected areas of the IPv6 address space not known to contain active hosts a priori.
no_new_dataset
0.945751
1609.04909
Shourya Roy
Shourya Roy, Himanshu S. Bhatt, Y. Narahari
An Iterative Transfer Learning Based Ensemble Technique for Automatic Short Answer Grading
null
null
null
null
cs.CL
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Automatic short answer grading (ASAG) techniques are designed to automatically assess short answers to questions in natural language, having a length of a few words to a few sentences. Supervised ASAG techniques have been demonstrated to be effective but suffer from a couple of key practical limitations. They are greatly reliant on instructor provided model answers and need labeled training data in the form of graded student answers for every assessment task. To overcome these, in this paper, we introduce an ASAG technique with two novel features. We propose an iterative technique on an ensemble of (a) a text classifier of student answers and (b) a classifier using numeric features derived from various similarity measures with respect to model answers. Second, we employ canonical correlation analysis based transfer learning on a common feature representation to build the classifier ensemble for questions having no labelled data. The proposed technique handsomely beats all winning supervised entries on the SCIENTSBANK dataset from the Student Response Analysis task of SemEval 2013. Additionally, we demonstrate generalizability and benefits of the proposed technique through evaluation on multiple ASAG datasets from different subject topics and standards.
[ { "version": "v1", "created": "Fri, 16 Sep 2016 04:58:54 GMT" }, { "version": "v2", "created": "Mon, 19 Sep 2016 01:28:17 GMT" }, { "version": "v3", "created": "Mon, 21 Nov 2016 13:44:09 GMT" } ]
2016-11-22T00:00:00
[ [ "Roy", "Shourya", "" ], [ "Bhatt", "Himanshu S.", "" ], [ "Narahari", "Y.", "" ] ]
TITLE: An Iterative Transfer Learning Based Ensemble Technique for Automatic Short Answer Grading ABSTRACT: Automatic short answer grading (ASAG) techniques are designed to automatically assess short answers to questions in natural language, having a length of a few words to a few sentences. Supervised ASAG techniques have been demonstrated to be effective but suffer from a couple of key practical limitations. They are greatly reliant on instructor provided model answers and need labeled training data in the form of graded student answers for every assessment task. To overcome these, in this paper, we introduce an ASAG technique with two novel features. We propose an iterative technique on an ensemble of (a) a text classifier of student answers and (b) a classifier using numeric features derived from various similarity measures with respect to model answers. Second, we employ canonical correlation analysis based transfer learning on a common feature representation to build the classifier ensemble for questions having no labelled data. The proposed technique handsomely beats all winning supervised entries on the SCIENTSBANK dataset from the Student Response Analysis task of SemEval 2013. Additionally, we demonstrate generalizability and benefits of the proposed technique through evaluation on multiple ASAG datasets from different subject topics and standards.
no_new_dataset
0.947672
1609.08039
Evgeny Burnaev
Evgeny Burnaev and Dmitry Smolyakov
One-Class SVM with Privileged Information and its Application to Malware Detection
8 pages, 5 figures, 3 tables
null
null
null
stat.ML cs.CR stat.AP
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
A number of important applied problems in engineering, finance and medicine can be formulated as a problem of anomaly detection. A classical approach to the problem is to describe a normal state using a one-class support vector machine. Then to detect anomalies we quantify a distance from a new observation to the constructed description of the normal class. In this paper we present a new approach to the one-class classification. We formulate a new problem statement and a corresponding algorithm that allow taking into account a privileged information during the training phase. We evaluate performance of the proposed approach using a synthetic dataset, as well as the publicly available Microsoft Malware Classification Challenge dataset.
[ { "version": "v1", "created": "Mon, 26 Sep 2016 16:01:02 GMT" }, { "version": "v2", "created": "Sun, 20 Nov 2016 16:31:46 GMT" } ]
2016-11-22T00:00:00
[ [ "Burnaev", "Evgeny", "" ], [ "Smolyakov", "Dmitry", "" ] ]
TITLE: One-Class SVM with Privileged Information and its Application to Malware Detection ABSTRACT: A number of important applied problems in engineering, finance and medicine can be formulated as a problem of anomaly detection. A classical approach to the problem is to describe a normal state using a one-class support vector machine. Then to detect anomalies we quantify a distance from a new observation to the constructed description of the normal class. In this paper we present a new approach to the one-class classification. We formulate a new problem statement and a corresponding algorithm that allow taking into account a privileged information during the training phase. We evaluate performance of the proposed approach using a synthetic dataset, as well as the publicly available Microsoft Malware Classification Challenge dataset.
no_new_dataset
0.944022
1611.05546
Damien Teney
Damien Teney, Anton van den Hengel
Zero-Shot Visual Question Answering
null
null
null
null
cs.CV cs.AI cs.CL
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Part of the appeal of Visual Question Answering (VQA) is its promise to answer new questions about previously unseen images. Most current methods demand training questions that illustrate every possible concept, and will therefore never achieve this capability, since the volume of required training data would be prohibitive. Answering general questions about images requires methods capable of Zero-Shot VQA, that is, methods able to answer questions beyond the scope of the training questions. We propose a new evaluation protocol for VQA methods which measures their ability to perform Zero-Shot VQA, and in doing so highlights significant practical deficiencies of current approaches, some of which are masked by the biases in current datasets. We propose and evaluate several strategies for achieving Zero-Shot VQA, including methods based on pretrained word embeddings, object classifiers with semantic embeddings, and test-time retrieval of example images. Our extensive experiments are intended to serve as baselines for Zero-Shot VQA, and they also achieve state-of-the-art performance in the standard VQA evaluation setting.
[ { "version": "v1", "created": "Thu, 17 Nov 2016 03:21:00 GMT" }, { "version": "v2", "created": "Sun, 20 Nov 2016 21:51:24 GMT" } ]
2016-11-22T00:00:00
[ [ "Teney", "Damien", "" ], [ "Hengel", "Anton van den", "" ] ]
TITLE: Zero-Shot Visual Question Answering ABSTRACT: Part of the appeal of Visual Question Answering (VQA) is its promise to answer new questions about previously unseen images. Most current methods demand training questions that illustrate every possible concept, and will therefore never achieve this capability, since the volume of required training data would be prohibitive. Answering general questions about images requires methods capable of Zero-Shot VQA, that is, methods able to answer questions beyond the scope of the training questions. We propose a new evaluation protocol for VQA methods which measures their ability to perform Zero-Shot VQA, and in doing so highlights significant practical deficiencies of current approaches, some of which are masked by the biases in current datasets. We propose and evaluate several strategies for achieving Zero-Shot VQA, including methods based on pretrained word embeddings, object classifiers with semantic embeddings, and test-time retrieval of example images. Our extensive experiments are intended to serve as baselines for Zero-Shot VQA, and they also achieve state-of-the-art performance in the standard VQA evaluation setting.
no_new_dataset
0.941169
1611.06362
Hong Liu
Hong Liu, Rongrong Ji, Yongjian Wu, Feiyue Huang
Ordinal Constrained Binary Code Learning for Nearest Neighbor Search
Accepted to AAAI 2017
null
null
null
cs.CV
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Recent years have witnessed extensive attention in binary code learning, a.k.a. hashing, for nearest neighbor search problems. It has been seen that high-dimensional data points can be quantized into binary codes to give an efficient similarity approximation via Hamming distance. Among existing schemes, ranking-based hashing is recent promising that targets at preserving ordinal relations of ranking in the Hamming space to minimize retrieval loss. However, the size of the ranking tuples, which shows the ordinal relations, is quadratic or cubic to the size of training samples. By given a large-scale training data set, it is very expensive to embed such ranking tuples in binary code learning. Besides, it remains a dificulty to build ranking tuples efficiently for most ranking-preserving hashing, which are deployed over an ordinal graph-based setting. To handle these problems, we propose a novel ranking-preserving hashing method, dubbed Ordinal Constraint Hashing (OCH), which efficiently learns the optimal hashing functions with a graph-based approximation to embed the ordinal relations. The core idea is to reduce the size of ordinal graph with ordinal constraint projection, which preserves the ordinal relations through a small data set (such as clusters or random samples). In particular, to learn such hash functions effectively, we further relax the discrete constraints and design a specific stochastic gradient decent algorithm for optimization. Experimental results on three large-scale visual search benchmark datasets, i.e. LabelMe, Tiny100K and GIST1M, show that the proposed OCH method can achieve superior performance over the state-of-the-arts approaches.
[ { "version": "v1", "created": "Sat, 19 Nov 2016 13:24:10 GMT" } ]
2016-11-22T00:00:00
[ [ "Liu", "Hong", "" ], [ "Ji", "Rongrong", "" ], [ "Wu", "Yongjian", "" ], [ "Huang", "Feiyue", "" ] ]
TITLE: Ordinal Constrained Binary Code Learning for Nearest Neighbor Search ABSTRACT: Recent years have witnessed extensive attention in binary code learning, a.k.a. hashing, for nearest neighbor search problems. It has been seen that high-dimensional data points can be quantized into binary codes to give an efficient similarity approximation via Hamming distance. Among existing schemes, ranking-based hashing is recent promising that targets at preserving ordinal relations of ranking in the Hamming space to minimize retrieval loss. However, the size of the ranking tuples, which shows the ordinal relations, is quadratic or cubic to the size of training samples. By given a large-scale training data set, it is very expensive to embed such ranking tuples in binary code learning. Besides, it remains a dificulty to build ranking tuples efficiently for most ranking-preserving hashing, which are deployed over an ordinal graph-based setting. To handle these problems, we propose a novel ranking-preserving hashing method, dubbed Ordinal Constraint Hashing (OCH), which efficiently learns the optimal hashing functions with a graph-based approximation to embed the ordinal relations. The core idea is to reduce the size of ordinal graph with ordinal constraint projection, which preserves the ordinal relations through a small data set (such as clusters or random samples). In particular, to learn such hash functions effectively, we further relax the discrete constraints and design a specific stochastic gradient decent algorithm for optimization. Experimental results on three large-scale visual search benchmark datasets, i.e. LabelMe, Tiny100K and GIST1M, show that the proposed OCH method can achieve superior performance over the state-of-the-arts approaches.
no_new_dataset
0.950915
1611.06495
Jiawei Zhang
Jiawei Zhang, Jinshan Pan, Wei-Sheng Lai, Rynson Lau, Ming-Hsuan Yang
Learning Fully Convolutional Networks for Iterative Non-blind Deconvolution
null
null
null
null
cs.CV
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
In this paper, we propose a fully convolutional networks for iterative non-blind deconvolution We decompose the non-blind deconvolution problem into image denoising and image deconvolution. We train a FCNN to remove noises in the gradient domain and use the learned gradients to guide the image deconvolution step. In contrast to the existing deep neural network based methods, we iteratively deconvolve the blurred images in a multi-stage framework. The proposed method is able to learn an adaptive image prior, which keeps both local (details) and global (structures) information. Both quantitative and qualitative evaluations on benchmark datasets demonstrate that the proposed method performs favorably against state-of-the-art algorithms in terms of quality and speed.
[ { "version": "v1", "created": "Sun, 20 Nov 2016 10:25:06 GMT" } ]
2016-11-22T00:00:00
[ [ "Zhang", "Jiawei", "" ], [ "Pan", "Jinshan", "" ], [ "Lai", "Wei-Sheng", "" ], [ "Lau", "Rynson", "" ], [ "Yang", "Ming-Hsuan", "" ] ]
TITLE: Learning Fully Convolutional Networks for Iterative Non-blind Deconvolution ABSTRACT: In this paper, we propose a fully convolutional networks for iterative non-blind deconvolution We decompose the non-blind deconvolution problem into image denoising and image deconvolution. We train a FCNN to remove noises in the gradient domain and use the learned gradients to guide the image deconvolution step. In contrast to the existing deep neural network based methods, we iteratively deconvolve the blurred images in a multi-stage framework. The proposed method is able to learn an adaptive image prior, which keeps both local (details) and global (structures) information. Both quantitative and qualitative evaluations on benchmark datasets demonstrate that the proposed method performs favorably against state-of-the-art algorithms in terms of quality and speed.
no_new_dataset
0.947381
1611.06539
Sebastian Vogel
Sebastian Vogel, Christoph Schorn, Andre Guntoro, Gerd Ascheid
Efficient Stochastic Inference of Bitwise Deep Neural Networks
6 pages, 3 figures, Workshop on Efficient Methods for Deep Neural Networks at Neural Information Processing Systems Conference 2016, NIPS 2016, EMDNN 2016
null
null
null
cs.NE cs.LG
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Recently published methods enable training of bitwise neural networks which allow reduced representation of down to a single bit per weight. We present a method that exploits ensemble decisions based on multiple stochastically sampled network models to increase performance figures of bitwise neural networks in terms of classification accuracy at inference. Our experiments with the CIFAR-10 and GTSRB datasets show that the performance of such network ensembles surpasses the performance of the high-precision base model. With this technique we achieve 5.81% best classification error on CIFAR-10 test set using bitwise networks. Concerning inference on embedded systems we evaluate these bitwise networks using a hardware efficient stochastic rounding procedure. Our work contributes to efficient embedded bitwise neural networks.
[ { "version": "v1", "created": "Sun, 20 Nov 2016 16:05:07 GMT" } ]
2016-11-22T00:00:00
[ [ "Vogel", "Sebastian", "" ], [ "Schorn", "Christoph", "" ], [ "Guntoro", "Andre", "" ], [ "Ascheid", "Gerd", "" ] ]
TITLE: Efficient Stochastic Inference of Bitwise Deep Neural Networks ABSTRACT: Recently published methods enable training of bitwise neural networks which allow reduced representation of down to a single bit per weight. We present a method that exploits ensemble decisions based on multiple stochastically sampled network models to increase performance figures of bitwise neural networks in terms of classification accuracy at inference. Our experiments with the CIFAR-10 and GTSRB datasets show that the performance of such network ensembles surpasses the performance of the high-precision base model. With this technique we achieve 5.81% best classification error on CIFAR-10 test set using bitwise networks. Concerning inference on embedded systems we evaluate these bitwise networks using a hardware efficient stochastic rounding procedure. Our work contributes to efficient embedded bitwise neural networks.
no_new_dataset
0.949763
1611.06625
Geli Fei
Huayi Li, Geli Fei, Shuai Wang, Bing Liu, Weixiang Shao, Arjun Mukherjee, Jidong Shao
Modeling Review Spam Using Temporal Patterns and Co-bursting Behaviors
null
null
null
null
cs.SI
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Online reviews play a crucial role in helping consumers evaluate and compare products and services. However, review hosting sites are often targeted by opinion spamming. In recent years, many such sites have put a great deal of effort in building effective review filtering systems to detect fake reviews and to block malicious accounts. Thus, fraudsters or spammers now turn to compromise, purchase or even raise reputable accounts to write fake reviews. Based on the analysis of a real-life dataset from a review hosting site (dianping.com), we discovered that reviewers' posting rates are bimodal and the transitions between different states can be utilized to differentiate spammers from genuine reviewers. Inspired by these findings, we propose a two-mode Labeled Hidden Markov Model to detect spammers. Experimental results show that our model significantly outperforms supervised learning using linguistic and behavioral features in identifying spammers. Furthermore, we found that when a product has a burst of reviews, many spammers are likely to be actively involved in writing reviews to the product as well as to many other products. We then propose a novel co-bursting network for detecting spammer groups. The co-bursting network enables us to produce more accurate spammer groups than the current state-of-the-art reviewer-product (co-reviewing) network.
[ { "version": "v1", "created": "Mon, 21 Nov 2016 01:13:42 GMT" } ]
2016-11-22T00:00:00
[ [ "Li", "Huayi", "" ], [ "Fei", "Geli", "" ], [ "Wang", "Shuai", "" ], [ "Liu", "Bing", "" ], [ "Shao", "Weixiang", "" ], [ "Mukherjee", "Arjun", "" ], [ "Shao", "Jidong", "" ] ]
TITLE: Modeling Review Spam Using Temporal Patterns and Co-bursting Behaviors ABSTRACT: Online reviews play a crucial role in helping consumers evaluate and compare products and services. However, review hosting sites are often targeted by opinion spamming. In recent years, many such sites have put a great deal of effort in building effective review filtering systems to detect fake reviews and to block malicious accounts. Thus, fraudsters or spammers now turn to compromise, purchase or even raise reputable accounts to write fake reviews. Based on the analysis of a real-life dataset from a review hosting site (dianping.com), we discovered that reviewers' posting rates are bimodal and the transitions between different states can be utilized to differentiate spammers from genuine reviewers. Inspired by these findings, we propose a two-mode Labeled Hidden Markov Model to detect spammers. Experimental results show that our model significantly outperforms supervised learning using linguistic and behavioral features in identifying spammers. Furthermore, we found that when a product has a burst of reviews, many spammers are likely to be actively involved in writing reviews to the product as well as to many other products. We then propose a novel co-bursting network for detecting spammer groups. The co-bursting network enables us to produce more accurate spammer groups than the current state-of-the-art reviewer-product (co-reviewing) network.
no_new_dataset
0.946399
1611.06638
Qiang Qiu
Jose Lezama, Qiang Qiu, Guillermo Sapiro
Not Afraid of the Dark: NIR-VIS Face Recognition via Cross-spectral Hallucination and Low-rank Embedding
null
null
null
null
cs.CV
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Surveillance cameras today often capture NIR (near infrared) images in low-light environments. However, most face datasets accessible for training and verification are only collected in the VIS (visible light) spectrum. It remains a challenging problem to match NIR to VIS face images due to the different light spectrum. Recently, breakthroughs have been made for VIS face recognition by applying deep learning on a huge amount of labeled VIS face samples. The same deep learning approach cannot be simply applied to NIR face recognition for two main reasons: First, much limited NIR face images are available for training compared to the VIS spectrum. Second, face galleries to be matched are mostly available only in the VIS spectrum. In this paper, we propose an approach to extend the deep learning breakthrough for VIS face recognition to the NIR spectrum, without retraining the underlying deep models that see only VIS faces. Our approach consists of two core components, cross-spectral hallucination and low-rank embedding, to optimize respectively input and output of a VIS deep model for cross-spectral face recognition. Cross-spectral hallucination produces VIS faces from NIR images through a deep learning approach. Low-rank embedding restores a low-rank structure for faces deep features across both NIR and VIS spectrum. We observe that it is often equally effective to perform hallucination to input NIR images or low-rank embedding to output deep features for a VIS deep model for cross-spectral recognition. When hallucination and low-rank embedding are deployed together, we observe significant further improvement; we obtain state-of-the-art accuracy on the CASIA NIR-VIS v2.0 benchmark, without the need at all to re-train the recognition system.
[ { "version": "v1", "created": "Mon, 21 Nov 2016 03:22:23 GMT" } ]
2016-11-22T00:00:00
[ [ "Lezama", "Jose", "" ], [ "Qiu", "Qiang", "" ], [ "Sapiro", "Guillermo", "" ] ]
TITLE: Not Afraid of the Dark: NIR-VIS Face Recognition via Cross-spectral Hallucination and Low-rank Embedding ABSTRACT: Surveillance cameras today often capture NIR (near infrared) images in low-light environments. However, most face datasets accessible for training and verification are only collected in the VIS (visible light) spectrum. It remains a challenging problem to match NIR to VIS face images due to the different light spectrum. Recently, breakthroughs have been made for VIS face recognition by applying deep learning on a huge amount of labeled VIS face samples. The same deep learning approach cannot be simply applied to NIR face recognition for two main reasons: First, much limited NIR face images are available for training compared to the VIS spectrum. Second, face galleries to be matched are mostly available only in the VIS spectrum. In this paper, we propose an approach to extend the deep learning breakthrough for VIS face recognition to the NIR spectrum, without retraining the underlying deep models that see only VIS faces. Our approach consists of two core components, cross-spectral hallucination and low-rank embedding, to optimize respectively input and output of a VIS deep model for cross-spectral face recognition. Cross-spectral hallucination produces VIS faces from NIR images through a deep learning approach. Low-rank embedding restores a low-rank structure for faces deep features across both NIR and VIS spectrum. We observe that it is often equally effective to perform hallucination to input NIR images or low-rank embedding to output deep features for a VIS deep model for cross-spectral recognition. When hallucination and low-rank embedding are deployed together, we observe significant further improvement; we obtain state-of-the-art accuracy on the CASIA NIR-VIS v2.0 benchmark, without the need at all to re-train the recognition system.
no_new_dataset
0.953319
1611.06671
Mark Magumba
Mark Abraham Magumba, Peter Nabende
Ontology Driven Disease Incidence Detection on Twitter
19 pages, 7 figures, 1 table
null
null
null
cs.CL cs.IR
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
In this work we address the issue of generic automated disease incidence monitoring on twitter. We employ an ontology of disease related concepts and use it to obtain a conceptual representation of tweets. Unlike previous key word based systems and topic modeling approaches, our ontological approach allows us to apply more stringent criteria for determining which messages are relevant such as spatial and temporal characteristics whilst giving a stronger guarantee that the resulting models will perform well on new data that may be lexically divergent. We achieve this by training learners on concepts rather than individual words. For training we use a dataset containing mentions of influenza and Listeria and use the learned models to classify datasets containing mentions of an arbitrary selection of other diseases. We show that our ontological approach achieves good performance on this task using a variety of Natural Language Processing Techniques. We also show that word vectors can be learned directly from our concepts to achieve even better results.
[ { "version": "v1", "created": "Mon, 21 Nov 2016 07:32:56 GMT" } ]
2016-11-22T00:00:00
[ [ "Magumba", "Mark Abraham", "" ], [ "Nabende", "Peter", "" ] ]
TITLE: Ontology Driven Disease Incidence Detection on Twitter ABSTRACT: In this work we address the issue of generic automated disease incidence monitoring on twitter. We employ an ontology of disease related concepts and use it to obtain a conceptual representation of tweets. Unlike previous key word based systems and topic modeling approaches, our ontological approach allows us to apply more stringent criteria for determining which messages are relevant such as spatial and temporal characteristics whilst giving a stronger guarantee that the resulting models will perform well on new data that may be lexically divergent. We achieve this by training learners on concepts rather than individual words. For training we use a dataset containing mentions of influenza and Listeria and use the learned models to classify datasets containing mentions of an arbitrary selection of other diseases. We show that our ontological approach achieves good performance on this task using a variety of Natural Language Processing Techniques. We also show that word vectors can be learned directly from our concepts to achieve even better results.
no_new_dataset
0.940079
1611.06678
Ali Diba
Ali Diba, Vivek Sharma, Luc Van Gool
Deep Temporal Linear Encoding Networks
Ali Diba and Vivek Sharma contributed equally to this work and listed in alphabetical order
null
null
null
cs.CV
http://creativecommons.org/licenses/by/4.0/
The CNN-encoding of features from entire videos for the representation of human actions has rarely been addressed. Instead, CNN work has focused on approaches to fuse spatial and temporal networks, but these were typically limited to processing shorter sequences. We present a new video representation, called temporal linear encoding (TLE) and embedded inside of CNNs as a new layer, which captures the appearance and motion throughout entire videos. It encodes this aggregated information into a robust video feature representation, via end-to-end learning. Advantages of TLEs are: (a) they encode the entire video into a compact feature representation, learning the semantics and a discriminative feature space; (b) they are applicable to all kinds of networks like 2D and 3D CNNs for video classification; and (c) they model feature interactions in a more expressive way and without loss of information. We conduct experiments on two challenging human action datasets: HMDB51 and UCF101. The experiments show that TLE outperforms current state-of-the-art methods on both datasets.
[ { "version": "v1", "created": "Mon, 21 Nov 2016 08:27:31 GMT" } ]
2016-11-22T00:00:00
[ [ "Diba", "Ali", "" ], [ "Sharma", "Vivek", "" ], [ "Van Gool", "Luc", "" ] ]
TITLE: Deep Temporal Linear Encoding Networks ABSTRACT: The CNN-encoding of features from entire videos for the representation of human actions has rarely been addressed. Instead, CNN work has focused on approaches to fuse spatial and temporal networks, but these were typically limited to processing shorter sequences. We present a new video representation, called temporal linear encoding (TLE) and embedded inside of CNNs as a new layer, which captures the appearance and motion throughout entire videos. It encodes this aggregated information into a robust video feature representation, via end-to-end learning. Advantages of TLEs are: (a) they encode the entire video into a compact feature representation, learning the semantics and a discriminative feature space; (b) they are applicable to all kinds of networks like 2D and 3D CNNs for video classification; and (c) they model feature interactions in a more expressive way and without loss of information. We conduct experiments on two challenging human action datasets: HMDB51 and UCF101. The experiments show that TLE outperforms current state-of-the-art methods on both datasets.
no_new_dataset
0.948489
1611.06683
HImanshu Aggarwal
Himanshu Aggarwal, Dinesh K. Vishwakarma
Covariate conscious approach for Gait recognition based upon Zernike moment invariants
11 pages
null
null
null
cs.CV
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Gait recognition i.e. identification of an individual from his/her walking pattern is an emerging field. While existing gait recognition techniques perform satisfactorily in normal walking conditions, there performance tend to suffer drastically with variations in clothing and carrying conditions. In this work, we propose a novel covariate cognizant framework to deal with the presence of such covariates. We describe gait motion by forming a single 2D spatio-temporal template from video sequence, called Average Energy Silhouette image (AESI). Zernike moment invariants (ZMIs) are then computed to screen the parts of AESI infected with covariates. Following this, features are extracted from Spatial Distribution of Oriented Gradients (SDOGs) and novel Mean of Directional Pixels (MDPs) methods. The obtained features are fused together to form the final well-endowed feature set. Experimental evaluation of the proposed framework on three publicly available datasets i.e. CASIA dataset B, OU-ISIR Treadmill dataset B and USF Human-ID challenge dataset with recently published gait recognition approaches, prove its superior performance.
[ { "version": "v1", "created": "Mon, 21 Nov 2016 08:48:47 GMT" } ]
2016-11-22T00:00:00
[ [ "Aggarwal", "Himanshu", "" ], [ "Vishwakarma", "Dinesh K.", "" ] ]
TITLE: Covariate conscious approach for Gait recognition based upon Zernike moment invariants ABSTRACT: Gait recognition i.e. identification of an individual from his/her walking pattern is an emerging field. While existing gait recognition techniques perform satisfactorily in normal walking conditions, there performance tend to suffer drastically with variations in clothing and carrying conditions. In this work, we propose a novel covariate cognizant framework to deal with the presence of such covariates. We describe gait motion by forming a single 2D spatio-temporal template from video sequence, called Average Energy Silhouette image (AESI). Zernike moment invariants (ZMIs) are then computed to screen the parts of AESI infected with covariates. Following this, features are extracted from Spatial Distribution of Oriented Gradients (SDOGs) and novel Mean of Directional Pixels (MDPs) methods. The obtained features are fused together to form the final well-endowed feature set. Experimental evaluation of the proposed framework on three publicly available datasets i.e. CASIA dataset B, OU-ISIR Treadmill dataset B and USF Human-ID challenge dataset with recently published gait recognition approaches, prove its superior performance.
no_new_dataset
0.935993
1611.06748
Di Kang
Di Kang, Debarun Dhar, Antoni B. Chan
Crowd Counting by Adapting Convolutional Neural Networks with Side Information
8 pages
null
null
null
cs.CV
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Computer vision tasks often have side information available that is helpful to solve the task. For example, for crowd counting, the camera perspective (e.g., camera angle and height) gives a clue about the appearance and scale of people in the scene. While side information has been shown to be useful for counting systems using traditional hand-crafted features, it has not been fully utilized in counting systems based on deep learning. In order to incorporate the available side information, we propose an adaptive convolutional neural network (ACNN), where the convolutional filter weights adapt to the current scene context via the side information. In particular, we model the filter weights as a low-dimensional manifold, parametrized by the side information, within the high-dimensional space of filter weights. With the help of side information and adaptive weights, the ACNN can disentangle the variations related to the side information, and extract discriminative features related to the current context. Since existing crowd counting datasets do not contain ground-truth side information, we collect a new dataset with the ground-truth camera angle and height as the side information. On experiments in crowd counting, the ACNN improves counting accuracy compared to a plain CNN with a similar number of parameters. We also apply ACNN to image deconvolution to show its potential effectiveness on other computer vision applications.
[ { "version": "v1", "created": "Mon, 21 Nov 2016 12:09:06 GMT" } ]
2016-11-22T00:00:00
[ [ "Kang", "Di", "" ], [ "Dhar", "Debarun", "" ], [ "Chan", "Antoni B.", "" ] ]
TITLE: Crowd Counting by Adapting Convolutional Neural Networks with Side Information ABSTRACT: Computer vision tasks often have side information available that is helpful to solve the task. For example, for crowd counting, the camera perspective (e.g., camera angle and height) gives a clue about the appearance and scale of people in the scene. While side information has been shown to be useful for counting systems using traditional hand-crafted features, it has not been fully utilized in counting systems based on deep learning. In order to incorporate the available side information, we propose an adaptive convolutional neural network (ACNN), where the convolutional filter weights adapt to the current scene context via the side information. In particular, we model the filter weights as a low-dimensional manifold, parametrized by the side information, within the high-dimensional space of filter weights. With the help of side information and adaptive weights, the ACNN can disentangle the variations related to the side information, and extract discriminative features related to the current context. Since existing crowd counting datasets do not contain ground-truth side information, we collect a new dataset with the ground-truth camera angle and height as the side information. On experiments in crowd counting, the ACNN improves counting accuracy compared to a plain CNN with a similar number of parameters. We also apply ACNN to image deconvolution to show its potential effectiveness on other computer vision applications.
new_dataset
0.952175
1611.06969
Raphael Felipe Prates
Raphael Prates and William Robson Schwartz
Kernel Cross-View Collaborative Representation based Classification for Person Re-Identification
Paper submitted to CVPR 2017 conference
null
null
null
cs.CV
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Person re-identification aims at the maintenance of a global identity as a person moves among non-overlapping surveillance cameras. It is a hard task due to different illumination conditions, viewpoints and the small number of annotated individuals from each pair of cameras (small-sample-size problem). Collaborative Representation based Classification (CRC) has been employed successfully to address the small-sample-size problem in computer vision. However, the original CRC formulation is not well-suited for person re-identification since it does not consider that probe and gallery samples are from different cameras. Furthermore, it is a linear model, while appearance changes caused by different camera conditions indicate a strong nonlinear transition between cameras. To overcome such limitations, we propose the Kernel Cross-View Collaborative Representation based Classification (Kernel X-CRC) that represents probe and gallery images by balancing representativeness and similarity nonlinearly. It assumes that a probe and its corresponding gallery image are represented with similar coding vectors using individuals from the training set. Experimental results demonstrate that our assumption is true when using a high-dimensional feature vector and becomes more compelling when dealing with a low-dimensional and discriminative representation computed using a common subspace learning method. We achieve state-of-the-art for rank-1 matching rates in two person re-identification datasets (PRID450S and GRID) and the second best results on VIPeR and CUHK01 datasets.
[ { "version": "v1", "created": "Mon, 21 Nov 2016 19:44:50 GMT" } ]
2016-11-22T00:00:00
[ [ "Prates", "Raphael", "" ], [ "Schwartz", "William Robson", "" ] ]
TITLE: Kernel Cross-View Collaborative Representation based Classification for Person Re-Identification ABSTRACT: Person re-identification aims at the maintenance of a global identity as a person moves among non-overlapping surveillance cameras. It is a hard task due to different illumination conditions, viewpoints and the small number of annotated individuals from each pair of cameras (small-sample-size problem). Collaborative Representation based Classification (CRC) has been employed successfully to address the small-sample-size problem in computer vision. However, the original CRC formulation is not well-suited for person re-identification since it does not consider that probe and gallery samples are from different cameras. Furthermore, it is a linear model, while appearance changes caused by different camera conditions indicate a strong nonlinear transition between cameras. To overcome such limitations, we propose the Kernel Cross-View Collaborative Representation based Classification (Kernel X-CRC) that represents probe and gallery images by balancing representativeness and similarity nonlinearly. It assumes that a probe and its corresponding gallery image are represented with similar coding vectors using individuals from the training set. Experimental results demonstrate that our assumption is true when using a high-dimensional feature vector and becomes more compelling when dealing with a low-dimensional and discriminative representation computed using a common subspace learning method. We achieve state-of-the-art for rank-1 matching rates in two person re-identification datasets (PRID450S and GRID) and the second best results on VIPeR and CUHK01 datasets.
no_new_dataset
0.953057
1611.06973
Seymour Knowles-Barley
Seymour Knowles-Barley, Verena Kaynig, Thouis Ray Jones, Alyssa Wilson, Joshua Morgan, Dongil Lee, Daniel Berger, Narayanan Kasthuri, Jeff W. Lichtman, Hanspeter Pfister
RhoanaNet Pipeline: Dense Automatic Neural Annotation
13 pages, 4 figures
null
null
null
q-bio.NC cs.CV
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Reconstructing a synaptic wiring diagram, or connectome, from electron microscopy (EM) images of brain tissue currently requires many hours of manual annotation or proofreading (Kasthuri and Lichtman, 2010; Lichtman and Sanes, 2008; Seung, 2009). The desire to reconstruct ever larger and more complex networks has pushed the collection of ever larger EM datasets. A cubic millimeter of raw imaging data would take up 1 PB of storage and present an annotation project that would be impractical without relying heavily on automatic segmentation methods. The RhoanaNet image processing pipeline was developed to automatically segment large volumes of EM data and ease the burden of manual proofreading and annotation. Based on (Kaynig et al., 2015), we updated every stage of the software pipeline to provide better throughput performance and higher quality segmentation results. We used state of the art deep learning techniques to generate improved membrane probability maps, and Gala (Nunez-Iglesias et al., 2014) was used to agglomerate 2D segments into 3D objects. We applied the RhoanaNet pipeline to four densely annotated EM datasets, two from mouse cortex, one from cerebellum and one from mouse lateral geniculate nucleus (LGN). All training and test data is made available for benchmark comparisons. The best segmentation results obtained gave $V^\text{Info}_\text{F-score}$ scores of 0.9054 and 09182 for the cortex datasets, 0.9438 for LGN, and 0.9150 for Cerebellum. The RhoanaNet pipeline is open source software. All source code, training data, test data, and annotations for all four benchmark datasets are available at www.rhoana.org.
[ { "version": "v1", "created": "Mon, 21 Nov 2016 19:48:29 GMT" } ]
2016-11-22T00:00:00
[ [ "Knowles-Barley", "Seymour", "" ], [ "Kaynig", "Verena", "" ], [ "Jones", "Thouis Ray", "" ], [ "Wilson", "Alyssa", "" ], [ "Morgan", "Joshua", "" ], [ "Lee", "Dongil", "" ], [ "Berger", "Daniel", "" ], [ "Kasthuri", "Narayanan", "" ], [ "Lichtman", "Jeff W.", "" ], [ "Pfister", "Hanspeter", "" ] ]
TITLE: RhoanaNet Pipeline: Dense Automatic Neural Annotation ABSTRACT: Reconstructing a synaptic wiring diagram, or connectome, from electron microscopy (EM) images of brain tissue currently requires many hours of manual annotation or proofreading (Kasthuri and Lichtman, 2010; Lichtman and Sanes, 2008; Seung, 2009). The desire to reconstruct ever larger and more complex networks has pushed the collection of ever larger EM datasets. A cubic millimeter of raw imaging data would take up 1 PB of storage and present an annotation project that would be impractical without relying heavily on automatic segmentation methods. The RhoanaNet image processing pipeline was developed to automatically segment large volumes of EM data and ease the burden of manual proofreading and annotation. Based on (Kaynig et al., 2015), we updated every stage of the software pipeline to provide better throughput performance and higher quality segmentation results. We used state of the art deep learning techniques to generate improved membrane probability maps, and Gala (Nunez-Iglesias et al., 2014) was used to agglomerate 2D segments into 3D objects. We applied the RhoanaNet pipeline to four densely annotated EM datasets, two from mouse cortex, one from cerebellum and one from mouse lateral geniculate nucleus (LGN). All training and test data is made available for benchmark comparisons. The best segmentation results obtained gave $V^\text{Info}_\text{F-score}$ scores of 0.9054 and 09182 for the cortex datasets, 0.9438 for LGN, and 0.9150 for Cerebellum. The RhoanaNet pipeline is open source software. All source code, training data, test data, and annotations for all four benchmark datasets are available at www.rhoana.org.
no_new_dataset
0.951549
1611.06997
Hongyuan Mei
Hongyuan Mei and Mohit Bansal and Matthew R. Walter
Coherent Dialogue with Attention-based Language Models
To appear at AAAI 2017
null
null
null
cs.CL cs.AI
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We model coherent conversation continuation via RNN-based dialogue models equipped with a dynamic attention mechanism. Our attention-RNN language model dynamically increases the scope of attention on the history as the conversation continues, as opposed to standard attention (or alignment) models with a fixed input scope in a sequence-to-sequence model. This allows each generated word to be associated with the most relevant words in its corresponding conversation history. We evaluate the model on two popular dialogue datasets, the open-domain MovieTriples dataset and the closed-domain Ubuntu Troubleshoot dataset, and achieve significant improvements over the state-of-the-art and baselines on several metrics, including complementary diversity-based metrics, human evaluation, and qualitative visualizations. We also show that a vanilla RNN with dynamic attention outperforms more complex memory models (e.g., LSTM and GRU) by allowing for flexible, long-distance memory. We promote further coherence via topic modeling-based reranking.
[ { "version": "v1", "created": "Mon, 21 Nov 2016 20:25:19 GMT" } ]
2016-11-22T00:00:00
[ [ "Mei", "Hongyuan", "" ], [ "Bansal", "Mohit", "" ], [ "Walter", "Matthew R.", "" ] ]
TITLE: Coherent Dialogue with Attention-based Language Models ABSTRACT: We model coherent conversation continuation via RNN-based dialogue models equipped with a dynamic attention mechanism. Our attention-RNN language model dynamically increases the scope of attention on the history as the conversation continues, as opposed to standard attention (or alignment) models with a fixed input scope in a sequence-to-sequence model. This allows each generated word to be associated with the most relevant words in its corresponding conversation history. We evaluate the model on two popular dialogue datasets, the open-domain MovieTriples dataset and the closed-domain Ubuntu Troubleshoot dataset, and achieve significant improvements over the state-of-the-art and baselines on several metrics, including complementary diversity-based metrics, human evaluation, and qualitative visualizations. We also show that a vanilla RNN with dynamic attention outperforms more complex memory models (e.g., LSTM and GRU) by allowing for flexible, long-distance memory. We promote further coherence via topic modeling-based reranking.
no_new_dataset
0.950134
1506.06318
Shang-Tse Chen
Shang-Tse Chen, Maria-Florina Balcan, Duen Horng Chau
Communication Efficient Distributed Agnostic Boosting
null
null
null
null
cs.LG stat.ML
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We consider the problem of learning from distributed data in the agnostic setting, i.e., in the presence of arbitrary forms of noise. Our main contribution is a general distributed boosting-based procedure for learning an arbitrary concept space, that is simultaneously noise tolerant, communication efficient, and computationally efficient. This improves significantly over prior works that were either communication efficient only in noise-free scenarios or computationally prohibitive. Empirical results on large synthetic and real-world datasets demonstrate the effectiveness and scalability of the proposed approach.
[ { "version": "v1", "created": "Sun, 21 Jun 2015 04:35:42 GMT" }, { "version": "v2", "created": "Fri, 18 Nov 2016 16:55:03 GMT" } ]
2016-11-21T00:00:00
[ [ "Chen", "Shang-Tse", "" ], [ "Balcan", "Maria-Florina", "" ], [ "Chau", "Duen Horng", "" ] ]
TITLE: Communication Efficient Distributed Agnostic Boosting ABSTRACT: We consider the problem of learning from distributed data in the agnostic setting, i.e., in the presence of arbitrary forms of noise. Our main contribution is a general distributed boosting-based procedure for learning an arbitrary concept space, that is simultaneously noise tolerant, communication efficient, and computationally efficient. This improves significantly over prior works that were either communication efficient only in noise-free scenarios or computationally prohibitive. Empirical results on large synthetic and real-world datasets demonstrate the effectiveness and scalability of the proposed approach.
no_new_dataset
0.950041
1510.08431
Christopher Grant
C. Grant and B. R. Littlejohn
Opportunities With Decay-At-Rest Neutrinos From Decay-In-Flight Neutrino Beams
6 pages, 3 figures
null
null
null
hep-ex hep-ph nucl-ex physics.ins-det
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Neutrino beam facilities, like spallation neutron facilities, produce copious quantities of neutrinos from the decay at rest of mesons and muons. The viability of decay-in-flight neutrino beams as sites for decay-at-rest neutrino studies has been investigated by calculating expected low-energy neutrino fluxes from the existing Fermilab NuMI beam facility. Decay-at-rest neutrino production in NuMI is found to be roughly equivalent per megawatt to that of spallation facilities, and is concentrated in the facility's target hall and beam stop regions. Interaction rates in 5 and 60 ton liquid argon detectors at a variety of existing and hypothetical locations along the beamline are found to be comparable to the largest existing decay-at-rest datasets for some channels. The physics implications and experimental challenges of such a measurement are discussed, along with prospects for measurements at targeted facilities along a future Fermilab long-baseline neutrino beam.
[ { "version": "v1", "created": "Wed, 28 Oct 2015 19:37:10 GMT" }, { "version": "v2", "created": "Mon, 16 Nov 2015 20:13:59 GMT" }, { "version": "v3", "created": "Thu, 17 Nov 2016 22:23:06 GMT" } ]
2016-11-21T00:00:00
[ [ "Grant", "C.", "" ], [ "Littlejohn", "B. R.", "" ] ]
TITLE: Opportunities With Decay-At-Rest Neutrinos From Decay-In-Flight Neutrino Beams ABSTRACT: Neutrino beam facilities, like spallation neutron facilities, produce copious quantities of neutrinos from the decay at rest of mesons and muons. The viability of decay-in-flight neutrino beams as sites for decay-at-rest neutrino studies has been investigated by calculating expected low-energy neutrino fluxes from the existing Fermilab NuMI beam facility. Decay-at-rest neutrino production in NuMI is found to be roughly equivalent per megawatt to that of spallation facilities, and is concentrated in the facility's target hall and beam stop regions. Interaction rates in 5 and 60 ton liquid argon detectors at a variety of existing and hypothetical locations along the beamline are found to be comparable to the largest existing decay-at-rest datasets for some channels. The physics implications and experimental challenges of such a measurement are discussed, along with prospects for measurements at targeted facilities along a future Fermilab long-baseline neutrino beam.
no_new_dataset
0.939137
1511.03719
Xiang Zhang
Xiang Zhang, Yann LeCun
Universum Prescription: Regularization using Unlabeled Data
7 pages for article, 3 pages for supplemental material. To appear in AAAI-17
null
null
null
cs.LG
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
This paper shows that simply prescribing "none of the above" labels to unlabeled data has a beneficial regularization effect to supervised learning. We call it universum prescription by the fact that the prescribed labels cannot be one of the supervised labels. In spite of its simplicity, universum prescription obtained competitive results in training deep convolutional networks for CIFAR-10, CIFAR-100, STL-10 and ImageNet datasets. A qualitative justification of these approaches using Rademacher complexity is presented. The effect of a regularization parameter -- probability of sampling from unlabeled data -- is also studied empirically.
[ { "version": "v1", "created": "Wed, 11 Nov 2015 22:46:46 GMT" }, { "version": "v2", "created": "Wed, 18 Nov 2015 19:54:22 GMT" }, { "version": "v3", "created": "Sun, 22 Nov 2015 22:12:09 GMT" }, { "version": "v4", "created": "Thu, 21 Jan 2016 06:11:33 GMT" }, { "version": "v5", "created": "Mon, 15 Feb 2016 18:52:30 GMT" }, { "version": "v6", "created": "Mon, 25 Apr 2016 21:10:32 GMT" }, { "version": "v7", "created": "Fri, 18 Nov 2016 01:15:30 GMT" } ]
2016-11-21T00:00:00
[ [ "Zhang", "Xiang", "" ], [ "LeCun", "Yann", "" ] ]
TITLE: Universum Prescription: Regularization using Unlabeled Data ABSTRACT: This paper shows that simply prescribing "none of the above" labels to unlabeled data has a beneficial regularization effect to supervised learning. We call it universum prescription by the fact that the prescribed labels cannot be one of the supervised labels. In spite of its simplicity, universum prescription obtained competitive results in training deep convolutional networks for CIFAR-10, CIFAR-100, STL-10 and ImageNet datasets. A qualitative justification of these approaches using Rademacher complexity is presented. The effect of a regularization parameter -- probability of sampling from unlabeled data -- is also studied empirically.
no_new_dataset
0.949389
1604.08354
Anne-Florence Bitbol
Anne-Florence Bitbol, Robert S. Dwyer, Lucy J. Colwell and Ned S. Wingreen
Inferring interaction partners from protein sequences
25 pages, 19 figures, published version
Proc. Natl. Acad. Sci. U.S.A., 113(43): 12180-12185 (2016)
10.1073/pnas.1606762113
null
physics.bio-ph q-bio.BM
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Specific protein-protein interactions are crucial in the cell, both to ensure the formation and stability of multi-protein complexes, and to enable signal transduction in various pathways. Functional interactions between proteins result in coevolution between the interaction partners, causing their sequences to be correlated. Here we exploit these correlations to accurately identify which proteins are specific interaction partners from sequence data alone. Our general approach, which employs a pairwise maximum entropy model to infer couplings between residues, has been successfully used to predict the three-dimensional structures of proteins from sequences. Thus inspired, we introduce an iterative algorithm to predict specific interaction partners from two protein families whose members are known to interact. We first assess the algorithm's performance on histidine kinases and response regulators from bacterial two-component signaling systems. We obtain a striking 0.93 true positive fraction on our complete dataset without any a priori knowledge of interaction partners, and we uncover the origin of this success. We then apply the algorithm to proteins from ATP-binding cassette (ABC) transporter complexes, and obtain accurate predictions in these systems as well. Finally, we present two metrics that accurately distinguish interacting protein families from non-interacting ones, using only sequence data.
[ { "version": "v1", "created": "Thu, 28 Apr 2016 09:23:57 GMT" }, { "version": "v2", "created": "Thu, 17 Nov 2016 21:29:46 GMT" } ]
2016-11-21T00:00:00
[ [ "Bitbol", "Anne-Florence", "" ], [ "Dwyer", "Robert S.", "" ], [ "Colwell", "Lucy J.", "" ], [ "Wingreen", "Ned S.", "" ] ]
TITLE: Inferring interaction partners from protein sequences ABSTRACT: Specific protein-protein interactions are crucial in the cell, both to ensure the formation and stability of multi-protein complexes, and to enable signal transduction in various pathways. Functional interactions between proteins result in coevolution between the interaction partners, causing their sequences to be correlated. Here we exploit these correlations to accurately identify which proteins are specific interaction partners from sequence data alone. Our general approach, which employs a pairwise maximum entropy model to infer couplings between residues, has been successfully used to predict the three-dimensional structures of proteins from sequences. Thus inspired, we introduce an iterative algorithm to predict specific interaction partners from two protein families whose members are known to interact. We first assess the algorithm's performance on histidine kinases and response regulators from bacterial two-component signaling systems. We obtain a striking 0.93 true positive fraction on our complete dataset without any a priori knowledge of interaction partners, and we uncover the origin of this success. We then apply the algorithm to proteins from ATP-binding cassette (ABC) transporter complexes, and obtain accurate predictions in these systems as well. Finally, we present two metrics that accurately distinguish interacting protein families from non-interacting ones, using only sequence data.
no_new_dataset
0.944791
1611.04023
Gerard Rinkus
Gerard J. Rinkus
Sparsey: Event Recognition via Deep Hierarchical Spare Distributed Codes
This is a manuscript form of a paper published in Frontiers in Computational Neuroscience in 2014 (http://dx.doi.org/10.3389/fncom.2014.00160). 65 pages, 28 figures, 8 tables
Frontiers in Computational Neuroscience, Vol. 8, Article 160 (2014)
10.3389/fncom.2014.00160
null
q-bio.NC cs.CV cs.NE
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Visual cortex's hierarchical, multi-level organization is captured in many biologically inspired computational vision models, the general idea being that progressively larger scale, more complex spatiotemporal features are represented in progressively higher areas. However, most earlier models use localist representations (codes) in each representational field, which we equate with the cortical macrocolumn (mac), at each level. In localism, each represented feature/event (item) is coded by a single unit. Our model, Sparsey, is also hierarchical but crucially, uses sparse distributed coding (SDC) in every mac in all levels. In SDC, each represented item is coded by a small subset of the mac's units. SDCs of different items can overlap and the size of overlap between items can represent their similarity. The difference between localism and SDC is crucial because SDC allows the two essential operations of associative memory, storing a new item and retrieving the best-matching stored item, to be done in fixed time for the life of the model. Since the model's core algorithm, which does both storage and retrieval (inference), makes a single pass over all macs on each time step, the overall model's storage/retrieval operation is also fixed-time, a criterion we consider essential for scalability to huge datasets. A 2010 paper described a nonhierarchical version of this model in the context of purely spatial pattern processing. Here, we elaborate a fully hierarchical model (arbitrary numbers of levels and macs per level), describing novel model principles like progressive critical periods, dynamic modulation of principal cells' activation functions based on a mac-level familiarity measure, representation of multiple simultaneously active hypotheses, a novel method of time warp invariant recognition, and we report results showing learning/recognition of spatiotemporal patterns.
[ { "version": "v1", "created": "Sat, 12 Nov 2016 17:35:23 GMT" } ]
2016-11-21T00:00:00
[ [ "Rinkus", "Gerard J.", "" ] ]
TITLE: Sparsey: Event Recognition via Deep Hierarchical Spare Distributed Codes ABSTRACT: Visual cortex's hierarchical, multi-level organization is captured in many biologically inspired computational vision models, the general idea being that progressively larger scale, more complex spatiotemporal features are represented in progressively higher areas. However, most earlier models use localist representations (codes) in each representational field, which we equate with the cortical macrocolumn (mac), at each level. In localism, each represented feature/event (item) is coded by a single unit. Our model, Sparsey, is also hierarchical but crucially, uses sparse distributed coding (SDC) in every mac in all levels. In SDC, each represented item is coded by a small subset of the mac's units. SDCs of different items can overlap and the size of overlap between items can represent their similarity. The difference between localism and SDC is crucial because SDC allows the two essential operations of associative memory, storing a new item and retrieving the best-matching stored item, to be done in fixed time for the life of the model. Since the model's core algorithm, which does both storage and retrieval (inference), makes a single pass over all macs on each time step, the overall model's storage/retrieval operation is also fixed-time, a criterion we consider essential for scalability to huge datasets. A 2010 paper described a nonhierarchical version of this model in the context of purely spatial pattern processing. Here, we elaborate a fully hierarchical model (arbitrary numbers of levels and macs per level), describing novel model principles like progressive critical periods, dynamic modulation of principal cells' activation functions based on a mac-level familiarity measure, representation of multiple simultaneously active hypotheses, a novel method of time warp invariant recognition, and we report results showing learning/recognition of spatiotemporal patterns.
no_new_dataset
0.953013
1611.05520
Mohammad Sadegh Aliakbarian
Mohammad Sadegh Aliakbarian, Fatemehsadat Saleh, Basura Fernando, Mathieu Salzmann, Lars Petersson, Lars Andersson
Deep Action- and Context-Aware Sequence Learning for Activity Recognition and Anticipation
10 pages, 4 figures, 7 tables
null
null
null
cs.CV
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Action recognition and anticipation are key to the success of many computer vision applications. Existing methods can roughly be grouped into those that extract global, context-aware representations of the entire image or sequence, and those that aim at focusing on the regions where the action occurs. While the former may suffer from the fact that context is not always reliable, the latter completely ignore this source of information, which can nonetheless be helpful in many situations. In this paper, we aim at making the best of both worlds by developing an approach that leverages both context-aware and action-aware features. At the core of our method lies a novel multi-stage recurrent architecture that allows us to effectively combine these two sources of information throughout a video. This architecture first exploits the global, context-aware features, and merges the resulting representation with the localized, action-aware ones. Our experiments on standard datasets evidence the benefits of our approach over methods that use each information type separately. We outperform the state-of-the-art methods that, as us, rely only on RGB frames as input for both action recognition and anticipation.
[ { "version": "v1", "created": "Thu, 17 Nov 2016 01:08:56 GMT" }, { "version": "v2", "created": "Fri, 18 Nov 2016 01:41:40 GMT" } ]
2016-11-21T00:00:00
[ [ "Aliakbarian", "Mohammad Sadegh", "" ], [ "Saleh", "Fatemehsadat", "" ], [ "Fernando", "Basura", "" ], [ "Salzmann", "Mathieu", "" ], [ "Petersson", "Lars", "" ], [ "Andersson", "Lars", "" ] ]
TITLE: Deep Action- and Context-Aware Sequence Learning for Activity Recognition and Anticipation ABSTRACT: Action recognition and anticipation are key to the success of many computer vision applications. Existing methods can roughly be grouped into those that extract global, context-aware representations of the entire image or sequence, and those that aim at focusing on the regions where the action occurs. While the former may suffer from the fact that context is not always reliable, the latter completely ignore this source of information, which can nonetheless be helpful in many situations. In this paper, we aim at making the best of both worlds by developing an approach that leverages both context-aware and action-aware features. At the core of our method lies a novel multi-stage recurrent architecture that allows us to effectively combine these two sources of information throughout a video. This architecture first exploits the global, context-aware features, and merges the resulting representation with the localized, action-aware ones. Our experiments on standard datasets evidence the benefits of our approach over methods that use each information type separately. We outperform the state-of-the-art methods that, as us, rely only on RGB frames as input for both action recognition and anticipation.
no_new_dataset
0.943608
1611.05896
Somak Aditya
Somak Aditya, Yezhou Yang, Chitta Baral, Yiannis Aloimonos
Answering Image Riddles using Vision and Reasoning through Probabilistic Soft Logic
14 pages, 10 figures
null
null
null
cs.CV cs.AI
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
In this work, we explore a genre of puzzles ("image riddles") which involves a set of images and a question. Answering these puzzles require both capabilities involving visual detection (including object, activity recognition) and, knowledge-based or commonsense reasoning. We compile a dataset of over 3k riddles where each riddle consists of 4 images and a groundtruth answer. The annotations are validated using crowd-sourced evaluation. We also define an automatic evaluation metric to track future progress. Our task bears similarity with the commonly known IQ tasks such as analogy solving, sequence filling that are often used to test intelligence. We develop a Probabilistic Reasoning-based approach that utilizes probabilistic commonsense knowledge to answer these riddles with a reasonable accuracy. We demonstrate the results of our approach using both automatic and human evaluations. Our approach achieves some promising results for these riddles and provides a strong baseline for future attempts. We make the entire dataset and related materials publicly available to the community in ImageRiddle Website (http://bit.ly/22f9Ala).
[ { "version": "v1", "created": "Thu, 17 Nov 2016 21:10:33 GMT" } ]
2016-11-21T00:00:00
[ [ "Aditya", "Somak", "" ], [ "Yang", "Yezhou", "" ], [ "Baral", "Chitta", "" ], [ "Aloimonos", "Yiannis", "" ] ]
TITLE: Answering Image Riddles using Vision and Reasoning through Probabilistic Soft Logic ABSTRACT: In this work, we explore a genre of puzzles ("image riddles") which involves a set of images and a question. Answering these puzzles require both capabilities involving visual detection (including object, activity recognition) and, knowledge-based or commonsense reasoning. We compile a dataset of over 3k riddles where each riddle consists of 4 images and a groundtruth answer. The annotations are validated using crowd-sourced evaluation. We also define an automatic evaluation metric to track future progress. Our task bears similarity with the commonly known IQ tasks such as analogy solving, sequence filling that are often used to test intelligence. We develop a Probabilistic Reasoning-based approach that utilizes probabilistic commonsense knowledge to answer these riddles with a reasonable accuracy. We demonstrate the results of our approach using both automatic and human evaluations. Our approach achieves some promising results for these riddles and provides a strong baseline for future attempts. We make the entire dataset and related materials publicly available to the community in ImageRiddle Website (http://bit.ly/22f9Ala).
new_dataset
0.954393
1611.05915
David Geronimo
David Ger\'onimo and Hedvig Kjellstr\"om
Generative One-Class Models for Text-based Person Retrieval in Forensic Applications
null
null
null
null
cs.CV
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Automatic forensic image analysis assists criminal investigation experts in the search for suspicious persons, abnormal behaviors detection and identity matching in images. In this paper we propose a person retrieval system that uses textual queries (e.g., "black trousers and green shirt") as descriptions and a one-class generative color model with outlier filtering to represent the images both to train the models and to perform the search. The method is evaluated in terms of its efficiency in fulfilling the needs of a forensic retrieval system: limited annotation, robustness, extensibility, adaptability and computational cost. The proposed generative method is compared to a corresponding discriminative approach. Experiments are carried out using a range of queries in three different databases. The experiments show that the two evaluated algorithms provide average retrieval performance and adaptable to new datasets. The proposed generative algorithm has some advantages over the discriminative one, specifically its capability to work with very few training samples and its much lower computational requirements when the number of training examples increases.
[ { "version": "v1", "created": "Thu, 17 Nov 2016 22:02:06 GMT" } ]
2016-11-21T00:00:00
[ [ "Gerónimo", "David", "" ], [ "Kjellström", "Hedvig", "" ] ]
TITLE: Generative One-Class Models for Text-based Person Retrieval in Forensic Applications ABSTRACT: Automatic forensic image analysis assists criminal investigation experts in the search for suspicious persons, abnormal behaviors detection and identity matching in images. In this paper we propose a person retrieval system that uses textual queries (e.g., "black trousers and green shirt") as descriptions and a one-class generative color model with outlier filtering to represent the images both to train the models and to perform the search. The method is evaluated in terms of its efficiency in fulfilling the needs of a forensic retrieval system: limited annotation, robustness, extensibility, adaptability and computational cost. The proposed generative method is compared to a corresponding discriminative approach. Experiments are carried out using a range of queries in three different databases. The experiments show that the two evaluated algorithms provide average retrieval performance and adaptable to new datasets. The proposed generative algorithm has some advantages over the discriminative one, specifically its capability to work with very few training samples and its much lower computational requirements when the number of training examples increases.
no_new_dataset
0.950732
1611.06049
Asim Ghosh Mr
Asim Ghosh, Daniel Monsivais, Kunal Bhattacharya, Robin I. M. Dunbar and Kimmo Kaski
Quantifying gender preferences across humans lifespan
12 pages, 8 figures
null
null
null
physics.soc-ph cs.SI q-bio.PE
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
In human relations individuals' gender and age play a key role in the structures and dynamics of their social arrangements. In order to analyze the gender preferences of individuals in interaction with others at different stages of their lives we study a large mobile phone dataset. To do this we consider four fundamental gender-related caller and callee combinations of human interactions, namely male to male, male to female, female to male, and female to female, which together with age, kinship, and different levels of friendship give rise to a wide scope of human sociality. Here we analyse the relative strength of these four types of interaction using a large dataset of mobile phone communication records. Our analysis suggests strong age dependence for an ego of one gender choosing to call an individual of either gender. We observe a strong opposite sex bonding across most of their reproductive age. However, older women show a strong tendency to connect to another female that is one generation younger in a way that is suggestive of the \emph{grandmothering effect}. We also find that the relative strength among the four possible interactions depends on phone call duration. For calls of medium and long duration, opposite gender interactions are significantly more probable than same gender interactions during the reproductive years, suggesting potential emotional exchange between spouses. By measuring the fraction of calls to other generations we find that mothers tend to make calls more to their daughters than to their sons, whereas fathers make calls more to their sons than to their daughters. For younger people, most of their calls go to same generation alters, while older people call the younger people more frequently, which supports the suggestion that \emph{affection flows downward}.
[ { "version": "v1", "created": "Fri, 18 Nov 2016 11:35:35 GMT" } ]
2016-11-21T00:00:00
[ [ "Ghosh", "Asim", "" ], [ "Monsivais", "Daniel", "" ], [ "Bhattacharya", "Kunal", "" ], [ "Dunbar", "Robin I. M.", "" ], [ "Kaski", "Kimmo", "" ] ]
TITLE: Quantifying gender preferences across humans lifespan ABSTRACT: In human relations individuals' gender and age play a key role in the structures and dynamics of their social arrangements. In order to analyze the gender preferences of individuals in interaction with others at different stages of their lives we study a large mobile phone dataset. To do this we consider four fundamental gender-related caller and callee combinations of human interactions, namely male to male, male to female, female to male, and female to female, which together with age, kinship, and different levels of friendship give rise to a wide scope of human sociality. Here we analyse the relative strength of these four types of interaction using a large dataset of mobile phone communication records. Our analysis suggests strong age dependence for an ego of one gender choosing to call an individual of either gender. We observe a strong opposite sex bonding across most of their reproductive age. However, older women show a strong tendency to connect to another female that is one generation younger in a way that is suggestive of the \emph{grandmothering effect}. We also find that the relative strength among the four possible interactions depends on phone call duration. For calls of medium and long duration, opposite gender interactions are significantly more probable than same gender interactions during the reproductive years, suggesting potential emotional exchange between spouses. By measuring the fraction of calls to other generations we find that mothers tend to make calls more to their daughters than to their sons, whereas fathers make calls more to their sons than to their daughters. For younger people, most of their calls go to same generation alters, while older people call the younger people more frequently, which supports the suggestion that \emph{affection flows downward}.
no_new_dataset
0.745537
1611.06067
Sijie Song
Sijie Song, Cuiling Lan, Junliang Xing, Wenjun Zeng, Jiaying Liu
An End-to-End Spatio-Temporal Attention Model for Human Action Recognition from Skeleton Data
null
null
null
null
cs.CV
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Human action recognition is an important task in computer vision. Extracting discriminative spatial and temporal features to model the spatial and temporal evolutions of different actions plays a key role in accomplishing this task. In this work, we propose an end-to-end spatial and temporal attention model for human action recognition from skeleton data. We build our model on top of the Recurrent Neural Networks (RNNs) with Long Short-Term Memory (LSTM), which learns to selectively focus on discriminative joints of skeleton within each frame of the inputs and pays different levels of attention to the outputs of different frames. Furthermore, to ensure effective training of the network, we propose a regularized cross-entropy loss to drive the model learning process and develop a joint training strategy accordingly. Experimental results demonstrate the effectiveness of the proposed model,both on the small human action recognition data set of SBU and the currently largest NTU dataset.
[ { "version": "v1", "created": "Fri, 18 Nov 2016 13:33:28 GMT" } ]
2016-11-21T00:00:00
[ [ "Song", "Sijie", "" ], [ "Lan", "Cuiling", "" ], [ "Xing", "Junliang", "" ], [ "Zeng", "Wenjun", "" ], [ "Liu", "Jiaying", "" ] ]
TITLE: An End-to-End Spatio-Temporal Attention Model for Human Action Recognition from Skeleton Data ABSTRACT: Human action recognition is an important task in computer vision. Extracting discriminative spatial and temporal features to model the spatial and temporal evolutions of different actions plays a key role in accomplishing this task. In this work, we propose an end-to-end spatial and temporal attention model for human action recognition from skeleton data. We build our model on top of the Recurrent Neural Networks (RNNs) with Long Short-Term Memory (LSTM), which learns to selectively focus on discriminative joints of skeleton within each frame of the inputs and pays different levels of attention to the outputs of different frames. Furthermore, to ensure effective training of the network, we propose a regularized cross-entropy loss to drive the model learning process and develop a joint training strategy accordingly. Experimental results demonstrate the effectiveness of the proposed model,both on the small human action recognition data set of SBU and the currently largest NTU dataset.
no_new_dataset
0.947527
1611.06080
Kian Hsiang Low
Quang Minh Hoang, Trong Nghia Hoang, Kian Hsiang Low
A Generalized Stochastic Variational Bayesian Hyperparameter Learning Framework for Sparse Spectrum Gaussian Process Regression
31st AAAI Conference on Artificial Intelligence (AAAI 2017), Extended version with proofs, 11 pages
null
null
null
stat.ML cs.LG
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
While much research effort has been dedicated to scaling up sparse Gaussian process (GP) models based on inducing variables for big data, little attention is afforded to the other less explored class of low-rank GP approximations that exploit the sparse spectral representation of a GP kernel. This paper presents such an effort to advance the state of the art of sparse spectrum GP models to achieve competitive predictive performance for massive datasets. Our generalized framework of stochastic variational Bayesian sparse spectrum GP (sVBSSGP) models addresses their shortcomings by adopting a Bayesian treatment of the spectral frequencies to avoid overfitting, modeling these frequencies jointly in its variational distribution to enable their interaction a posteriori, and exploiting local data for boosting the predictive performance. However, such structural improvements result in a variational lower bound that is intractable to be optimized. To resolve this, we exploit a variational parameterization trick to make it amenable to stochastic optimization. Interestingly, the resulting stochastic gradient has a linearly decomposable structure that can be exploited to refine our stochastic optimization method to incur constant time per iteration while preserving its property of being an unbiased estimator of the exact gradient of the variational lower bound. Empirical evaluation on real-world datasets shows that sVBSSGP outperforms state-of-the-art stochastic implementations of sparse GP models.
[ { "version": "v1", "created": "Fri, 18 Nov 2016 14:00:48 GMT" } ]
2016-11-21T00:00:00
[ [ "Hoang", "Quang Minh", "" ], [ "Hoang", "Trong Nghia", "" ], [ "Low", "Kian Hsiang", "" ] ]
TITLE: A Generalized Stochastic Variational Bayesian Hyperparameter Learning Framework for Sparse Spectrum Gaussian Process Regression ABSTRACT: While much research effort has been dedicated to scaling up sparse Gaussian process (GP) models based on inducing variables for big data, little attention is afforded to the other less explored class of low-rank GP approximations that exploit the sparse spectral representation of a GP kernel. This paper presents such an effort to advance the state of the art of sparse spectrum GP models to achieve competitive predictive performance for massive datasets. Our generalized framework of stochastic variational Bayesian sparse spectrum GP (sVBSSGP) models addresses their shortcomings by adopting a Bayesian treatment of the spectral frequencies to avoid overfitting, modeling these frequencies jointly in its variational distribution to enable their interaction a posteriori, and exploiting local data for boosting the predictive performance. However, such structural improvements result in a variational lower bound that is intractable to be optimized. To resolve this, we exploit a variational parameterization trick to make it amenable to stochastic optimization. Interestingly, the resulting stochastic gradient has a linearly decomposable structure that can be exploited to refine our stochastic optimization method to incur constant time per iteration while preserving its property of being an unbiased estimator of the exact gradient of the variational lower bound. Empirical evaluation on real-world datasets shows that sVBSSGP outperforms state-of-the-art stochastic implementations of sparse GP models.
no_new_dataset
0.946843
1611.06128
Mohamed Sherif
Mohamed Ahmed Sherif, Kevin Dre{\ss}ler, Panayiotis Smeros and Axel-Cyrille Ngonga Ngomo
Annex: Radon - Rapid Discovery of Topological Relations
19 pages, 3 figures, i algorithm and 1 table
null
null
null
cs.DB
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Datasets containing geo-spatial resources are increasingly being represented according to the Linked Data principles. Several time-efficient approaches for discovering links between RDF resources have been developed over the last years. However, the time-efficient discovery of topological relations between geospatial resources has been paid little attention to. We address this research gap by presenting Radon, a novel approach for the rapid computation of topological relations between geo-spatial resources. Our approach uses a sparse tiling index in combination with minimum bounding boxes to reduce the computation time of topological relations. Our evaluation of Radon's runtime on 45 datasets and in more than 800 experiments shows that it outperforms the state of the art by up to 3 orders of magnitude while maintaining an F-measure of 100%. Moreover, our experiments suggest that Radon scales up well when implemented in parallel.
[ { "version": "v1", "created": "Fri, 18 Nov 2016 15:42:22 GMT" } ]
2016-11-21T00:00:00
[ [ "Sherif", "Mohamed Ahmed", "" ], [ "Dreßler", "Kevin", "" ], [ "Smeros", "Panayiotis", "" ], [ "Ngomo", "Axel-Cyrille Ngonga", "" ] ]
TITLE: Annex: Radon - Rapid Discovery of Topological Relations ABSTRACT: Datasets containing geo-spatial resources are increasingly being represented according to the Linked Data principles. Several time-efficient approaches for discovering links between RDF resources have been developed over the last years. However, the time-efficient discovery of topological relations between geospatial resources has been paid little attention to. We address this research gap by presenting Radon, a novel approach for the rapid computation of topological relations between geo-spatial resources. Our approach uses a sparse tiling index in combination with minimum bounding boxes to reduce the computation time of topological relations. Our evaluation of Radon's runtime on 45 datasets and in more than 800 experiments shows that it outperforms the state of the art by up to 3 orders of magnitude while maintaining an F-measure of 100%. Moreover, our experiments suggest that Radon scales up well when implemented in parallel.
no_new_dataset
0.946794
1611.06132
Pavel Izmailov
Pavel Izmailov and Dmitry Kropotov
Faster variational inducing input Gaussian process classification
null
null
null
null
cs.LG cs.AI stat.ML
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Gaussian processes (GP) provide a prior over functions and allow finding complex regularities in data. Gaussian processes are successfully used for classification/regression problems and dimensionality reduction. In this work we consider the classification problem only. The complexity of standard methods for GP-classification scales cubically with the size of the training dataset. This complexity makes them inapplicable to big data problems. Therefore, a variety of methods were introduced to overcome this limitation. In the paper we focus on methods based on so called inducing inputs. This approach is based on variational inference and proposes a particular lower bound for marginal likelihood (evidence). This bound is then maximized w.r.t. parameters of kernel function of the Gaussian process, thus fitting the model to data. The computational complexity of this method is $O(nm^2)$, where $m$ is the number of inducing inputs used by the model and is assumed to be substantially smaller than the size of the dataset $n$. Recently, a new evidence lower bound for GP-classification problem was introduced. It allows using stochastic optimization, which makes it suitable for big data problems. However, the new lower bound depends on $O(m^2)$ variational parameter, which makes optimization challenging in case of big m. In this work we develop a new approach for training inducing input GP models for classification problems. Here we use quadratic approximation of several terms in the aforementioned evidence lower bound, obtaining analytical expressions for optimal values of most of the parameters in the optimization, thus sufficiently reducing the dimension of optimization space. In our experiments we achieve as well or better results, compared to the existing method. Moreover, our method doesn't require the user to manually set the learning rate, making it more practical, than the existing method.
[ { "version": "v1", "created": "Fri, 18 Nov 2016 15:53:50 GMT" } ]
2016-11-21T00:00:00
[ [ "Izmailov", "Pavel", "" ], [ "Kropotov", "Dmitry", "" ] ]
TITLE: Faster variational inducing input Gaussian process classification ABSTRACT: Gaussian processes (GP) provide a prior over functions and allow finding complex regularities in data. Gaussian processes are successfully used for classification/regression problems and dimensionality reduction. In this work we consider the classification problem only. The complexity of standard methods for GP-classification scales cubically with the size of the training dataset. This complexity makes them inapplicable to big data problems. Therefore, a variety of methods were introduced to overcome this limitation. In the paper we focus on methods based on so called inducing inputs. This approach is based on variational inference and proposes a particular lower bound for marginal likelihood (evidence). This bound is then maximized w.r.t. parameters of kernel function of the Gaussian process, thus fitting the model to data. The computational complexity of this method is $O(nm^2)$, where $m$ is the number of inducing inputs used by the model and is assumed to be substantially smaller than the size of the dataset $n$. Recently, a new evidence lower bound for GP-classification problem was introduced. It allows using stochastic optimization, which makes it suitable for big data problems. However, the new lower bound depends on $O(m^2)$ variational parameter, which makes optimization challenging in case of big m. In this work we develop a new approach for training inducing input GP models for classification problems. Here we use quadratic approximation of several terms in the aforementioned evidence lower bound, obtaining analytical expressions for optimal values of most of the parameters in the optimization, thus sufficiently reducing the dimension of optimization space. In our experiments we achieve as well or better results, compared to the existing method. Moreover, our method doesn't require the user to manually set the learning rate, making it more practical, than the existing method.
no_new_dataset
0.947672
1611.06211
Mohammad Babaeizadeh
Mohammad Babaeizadeh, Paris Smaragdis, Roy H. Campbell
NoiseOut: A Simple Way to Prune Neural Networks
null
null
null
null
cs.NE cs.CV
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Neural networks are usually over-parameterized with significant redundancy in the number of required neurons which results in unnecessary computation and memory usage at inference time. One common approach to address this issue is to prune these big networks by removing extra neurons and parameters while maintaining the accuracy. In this paper, we propose NoiseOut, a fully automated pruning algorithm based on the correlation between activations of neurons in the hidden layers. We prove that adding additional output neurons with entirely random targets results into a higher correlation between neurons which makes pruning by NoiseOut even more efficient. Finally, we test our method on various networks and datasets. These experiments exhibit high pruning rates while maintaining the accuracy of the original network.
[ { "version": "v1", "created": "Fri, 18 Nov 2016 19:55:29 GMT" } ]
2016-11-21T00:00:00
[ [ "Babaeizadeh", "Mohammad", "" ], [ "Smaragdis", "Paris", "" ], [ "Campbell", "Roy H.", "" ] ]
TITLE: NoiseOut: A Simple Way to Prune Neural Networks ABSTRACT: Neural networks are usually over-parameterized with significant redundancy in the number of required neurons which results in unnecessary computation and memory usage at inference time. One common approach to address this issue is to prune these big networks by removing extra neurons and parameters while maintaining the accuracy. In this paper, we propose NoiseOut, a fully automated pruning algorithm based on the correlation between activations of neurons in the hidden layers. We prove that adding additional output neurons with entirely random targets results into a higher correlation between neurons which makes pruning by NoiseOut even more efficient. Finally, we test our method on various networks and datasets. These experiments exhibit high pruning rates while maintaining the accuracy of the original network.
no_new_dataset
0.951142
1611.06224
Hui Miao
Hui Miao, Ang Li, Larry S. Davis, Amol Deshpande
ModelHub: Towards Unified Data and Lifecycle Management for Deep Learning
null
null
null
null
cs.DB cs.CV
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Deep learning has improved state-of-the-art results in many important fields, and has been the subject of much research in recent years, leading to the development of several systems for facilitating deep learning. Current systems, however, mainly focus on model building and training phases, while the issues of data management, model sharing, and lifecycle management are largely ignored. Deep learning modeling lifecycle generates a rich set of data artifacts, such as learned parameters and training logs, and comprises of several frequently conducted tasks, e.g., to understand the model behaviors and to try out new models. Dealing with such artifacts and tasks is cumbersome and largely left to the users. This paper describes our vision and implementation of a data and lifecycle management system for deep learning. First, we generalize model exploration and model enumeration queries from commonly conducted tasks by deep learning modelers, and propose a high-level domain specific language (DSL), inspired by SQL, to raise the abstraction level and accelerate the modeling process. To manage the data artifacts, especially the large amount of checkpointed float parameters, we design a novel model versioning system (dlv), and a read-optimized parameter archival storage system (PAS) that minimizes storage footprint and accelerates query workloads without losing accuracy. PAS archives versioned models using deltas in a multi-resolution fashion by separately storing the less significant bits, and features a novel progressive query (inference) evaluation algorithm. Third, we show that archiving versioned models using deltas poses a new dataset versioning problem and we develop efficient algorithms for solving it. We conduct extensive experiments over several real datasets from computer vision domain to show the efficiency of the proposed techniques.
[ { "version": "v1", "created": "Fri, 18 Nov 2016 20:59:25 GMT" } ]
2016-11-21T00:00:00
[ [ "Miao", "Hui", "" ], [ "Li", "Ang", "" ], [ "Davis", "Larry S.", "" ], [ "Deshpande", "Amol", "" ] ]
TITLE: ModelHub: Towards Unified Data and Lifecycle Management for Deep Learning ABSTRACT: Deep learning has improved state-of-the-art results in many important fields, and has been the subject of much research in recent years, leading to the development of several systems for facilitating deep learning. Current systems, however, mainly focus on model building and training phases, while the issues of data management, model sharing, and lifecycle management are largely ignored. Deep learning modeling lifecycle generates a rich set of data artifacts, such as learned parameters and training logs, and comprises of several frequently conducted tasks, e.g., to understand the model behaviors and to try out new models. Dealing with such artifacts and tasks is cumbersome and largely left to the users. This paper describes our vision and implementation of a data and lifecycle management system for deep learning. First, we generalize model exploration and model enumeration queries from commonly conducted tasks by deep learning modelers, and propose a high-level domain specific language (DSL), inspired by SQL, to raise the abstraction level and accelerate the modeling process. To manage the data artifacts, especially the large amount of checkpointed float parameters, we design a novel model versioning system (dlv), and a read-optimized parameter archival storage system (PAS) that minimizes storage footprint and accelerates query workloads without losing accuracy. PAS archives versioned models using deltas in a multi-resolution fashion by separately storing the less significant bits, and features a novel progressive query (inference) evaluation algorithm. Third, we show that archiving versioned models using deltas poses a new dataset versioning problem and we develop efficient algorithms for solving it. We conduct extensive experiments over several real datasets from computer vision domain to show the efficiency of the proposed techniques.
no_new_dataset
0.952794
1006.1772
Kishor Barman
Kishor Barman, Onkar Dabeer
Analysis of a Collaborative Filter Based on Popularity Amongst Neighbors
47 pages. Submitted to IEEE Transactions on Information Theory (revised in July 2011). A shorter version would be presented at ISIT 2010
null
10.1109/TIT.2012.2216980
null
cs.IT math.IT
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
In this paper, we analyze a collaborative filter that answers the simple question: What is popular amongst your friends? While this basic principle seems to be prevalent in many practical implementations, there does not appear to be much theoretical analysis of its performance. In this paper, we partly fill this gap. While recent works on this topic, such as the low-rank matrix completion literature, consider the probability of error in recovering the entire rating matrix, we consider probability of an error in an individual recommendation (bit error rate (BER)). For a mathematical model introduced in [1],[2], we identify three regimes of operation for our algorithm (named Popularity Amongst Friends (PAF)) in the limit as the matrix size grows to infinity. In a regime characterized by large number of samples and small degrees of freedom (defined precisely for the model in the paper), the asymptotic BER is zero; in a regime characterized by large number of samples and large degrees of freedom, the asymptotic BER is bounded away from 0 and 1/2 (and is identified exactly except for a special case); and in a regime characterized by a small number of samples, the algorithm fails. We also present numerical results for the MovieLens and Netflix datasets. We discuss the empirical performance in light of our theoretical results and compare with an approach based on low-rank matrix completion.
[ { "version": "v1", "created": "Wed, 9 Jun 2010 11:48:53 GMT" }, { "version": "v2", "created": "Thu, 14 Jul 2011 10:58:41 GMT" }, { "version": "v3", "created": "Fri, 15 Jul 2011 07:29:19 GMT" } ]
2016-11-18T00:00:00
[ [ "Barman", "Kishor", "" ], [ "Dabeer", "Onkar", "" ] ]
TITLE: Analysis of a Collaborative Filter Based on Popularity Amongst Neighbors ABSTRACT: In this paper, we analyze a collaborative filter that answers the simple question: What is popular amongst your friends? While this basic principle seems to be prevalent in many practical implementations, there does not appear to be much theoretical analysis of its performance. In this paper, we partly fill this gap. While recent works on this topic, such as the low-rank matrix completion literature, consider the probability of error in recovering the entire rating matrix, we consider probability of an error in an individual recommendation (bit error rate (BER)). For a mathematical model introduced in [1],[2], we identify three regimes of operation for our algorithm (named Popularity Amongst Friends (PAF)) in the limit as the matrix size grows to infinity. In a regime characterized by large number of samples and small degrees of freedom (defined precisely for the model in the paper), the asymptotic BER is zero; in a regime characterized by large number of samples and large degrees of freedom, the asymptotic BER is bounded away from 0 and 1/2 (and is identified exactly except for a special case); and in a regime characterized by a small number of samples, the algorithm fails. We also present numerical results for the MovieLens and Netflix datasets. We discuss the empirical performance in light of our theoretical results and compare with an approach based on low-rank matrix completion.
no_new_dataset
0.949669
1009.2275
Anh Le
Anh Le, Athina Markopoulou, Michalis Faloutsos
PhishDef: URL Names Say It All
9 pages, submitted to IEEE INFOCOM 2011
null
10.1109/INFCOM.2011.5934995
null
cs.CR cs.LG cs.NI
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Phishing is an increasingly sophisticated method to steal personal user information using sites that pretend to be legitimate. In this paper, we take the following steps to identify phishing URLs. First, we carefully select lexical features of the URLs that are resistant to obfuscation techniques used by attackers. Second, we evaluate the classification accuracy when using only lexical features, both automatically and hand-selected, vs. when using additional features. We show that lexical features are sufficient for all practical purposes. Third, we thoroughly compare several classification algorithms, and we propose to use an online method (AROW) that is able to overcome noisy training data. Based on the insights gained from our analysis, we propose PhishDef, a phishing detection system that uses only URL names and combines the above three elements. PhishDef is a highly accurate method (when compared to state-of-the-art approaches over real datasets), lightweight (thus appropriate for online and client-side deployment), proactive (based on online classification rather than blacklists), and resilient to training data inaccuracies (thus enabling the use of large noisy training data).
[ { "version": "v1", "created": "Sun, 12 Sep 2010 23:55:00 GMT" } ]
2016-11-18T00:00:00
[ [ "Le", "Anh", "" ], [ "Markopoulou", "Athina", "" ], [ "Faloutsos", "Michalis", "" ] ]
TITLE: PhishDef: URL Names Say It All ABSTRACT: Phishing is an increasingly sophisticated method to steal personal user information using sites that pretend to be legitimate. In this paper, we take the following steps to identify phishing URLs. First, we carefully select lexical features of the URLs that are resistant to obfuscation techniques used by attackers. Second, we evaluate the classification accuracy when using only lexical features, both automatically and hand-selected, vs. when using additional features. We show that lexical features are sufficient for all practical purposes. Third, we thoroughly compare several classification algorithms, and we propose to use an online method (AROW) that is able to overcome noisy training data. Based on the insights gained from our analysis, we propose PhishDef, a phishing detection system that uses only URL names and combines the above three elements. PhishDef is a highly accurate method (when compared to state-of-the-art approaches over real datasets), lightweight (thus appropriate for online and client-side deployment), proactive (based on online classification rather than blacklists), and resilient to training data inaccuracies (thus enabling the use of large noisy training data).
no_new_dataset
0.948202
1012.3189
Jian Li
Jian Li, Amol Deshpande
Maximizing Expected Utility for Stochastic Combinatorial Optimization Problems
31 pages, Preliminary version appears in the Proceeding of the 52nd Annual IEEE Symposium on Foundations of Computer Science (FOCS 2011), This version contains several new results ( results (2) and (3) in the abstract)
null
10.1109/FOCS.2011.33
null
cs.DS cs.DB
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We study the stochastic versions of a broad class of combinatorial problems where the weights of the elements in the input dataset are uncertain. The class of problems that we study includes shortest paths, minimum weight spanning trees, and minimum weight matchings, and other combinatorial problems like knapsack. We observe that the expected value is inadequate in capturing different types of {\em risk-averse} or {\em risk-prone} behaviors, and instead we consider a more general objective which is to maximize the {\em expected utility} of the solution for some given utility function, rather than the expected weight (expected weight becomes a special case). Under the assumption that there is a pseudopolynomial time algorithm for the {\em exact} version of the problem (This is true for the problems mentioned above), we can obtain the following approximation results for several important classes of utility functions: (1) If the utility function $\uti$ is continuous, upper-bounded by a constant and $\lim_{x\rightarrow+\infty}\uti(x)=0$, we show that we can obtain a polynomial time approximation algorithm with an {\em additive error} $\epsilon$ for any constant $\epsilon>0$. (2) If the utility function $\uti$ is a concave increasing function, we can obtain a polynomial time approximation scheme (PTAS). (3) If the utility function $\uti$ is increasing and has a bounded derivative, we can obtain a polynomial time approximation scheme. Our results recover or generalize several prior results on stochastic shortest path, stochastic spanning tree, and stochastic knapsack. Our algorithm for utility maximization makes use of the separability of exponential utility and a technique to decompose a general utility function into exponential utility functions, which may be useful in other stochastic optimization problems.
[ { "version": "v1", "created": "Tue, 14 Dec 2010 22:34:32 GMT" }, { "version": "v2", "created": "Fri, 15 Apr 2011 01:10:47 GMT" }, { "version": "v3", "created": "Sun, 14 Aug 2011 02:53:22 GMT" }, { "version": "v4", "created": "Fri, 19 Aug 2011 10:32:48 GMT" }, { "version": "v5", "created": "Tue, 19 Mar 2013 09:11:30 GMT" }, { "version": "v6", "created": "Sat, 19 Dec 2015 10:13:56 GMT" }, { "version": "v7", "created": "Wed, 10 Aug 2016 09:02:50 GMT" } ]
2016-11-18T00:00:00
[ [ "Li", "Jian", "" ], [ "Deshpande", "Amol", "" ] ]
TITLE: Maximizing Expected Utility for Stochastic Combinatorial Optimization Problems ABSTRACT: We study the stochastic versions of a broad class of combinatorial problems where the weights of the elements in the input dataset are uncertain. The class of problems that we study includes shortest paths, minimum weight spanning trees, and minimum weight matchings, and other combinatorial problems like knapsack. We observe that the expected value is inadequate in capturing different types of {\em risk-averse} or {\em risk-prone} behaviors, and instead we consider a more general objective which is to maximize the {\em expected utility} of the solution for some given utility function, rather than the expected weight (expected weight becomes a special case). Under the assumption that there is a pseudopolynomial time algorithm for the {\em exact} version of the problem (This is true for the problems mentioned above), we can obtain the following approximation results for several important classes of utility functions: (1) If the utility function $\uti$ is continuous, upper-bounded by a constant and $\lim_{x\rightarrow+\infty}\uti(x)=0$, we show that we can obtain a polynomial time approximation algorithm with an {\em additive error} $\epsilon$ for any constant $\epsilon>0$. (2) If the utility function $\uti$ is a concave increasing function, we can obtain a polynomial time approximation scheme (PTAS). (3) If the utility function $\uti$ is increasing and has a bounded derivative, we can obtain a polynomial time approximation scheme. Our results recover or generalize several prior results on stochastic shortest path, stochastic spanning tree, and stochastic knapsack. Our algorithm for utility maximization makes use of the separability of exponential utility and a technique to decompose a general utility function into exponential utility functions, which may be useful in other stochastic optimization problems.
no_new_dataset
0.948822
1105.2264
Artem Chebotko
Craig Franke, Samuel Morin, Artem Chebotko, John Abraham, Pearl Brazier
Distributed Semantic Web Data Management in HBase and MySQL Cluster
In Proc. of the 4th IEEE International Conference on Cloud Computing (CLOUD'11)
null
10.1109/CLOUD.2011.19
null
cs.DB cs.PF
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Various computing and data resources on the Web are being enhanced with machine-interpretable semantic descriptions to facilitate better search, discovery and integration. This interconnected metadata constitutes the Semantic Web, whose volume can potentially grow the scale of the Web. Efficient management of Semantic Web data, expressed using the W3C's Resource Description Framework (RDF), is crucial for supporting new data-intensive, semantics-enabled applications. In this work, we study and compare two approaches to distributed RDF data management based on emerging cloud computing technologies and traditional relational database clustering technologies. In particular, we design distributed RDF data storage and querying schemes for HBase and MySQL Cluster and conduct an empirical comparison of these approaches on a cluster of commodity machines using datasets and queries from the Third Provenance Challenge and Lehigh University Benchmark. Our study reveals interesting patterns in query evaluation, shows that our algorithms are promising, and suggests that cloud computing has a great potential for scalable Semantic Web data management.
[ { "version": "v1", "created": "Wed, 11 May 2011 17:46:15 GMT" } ]
2016-11-18T00:00:00
[ [ "Franke", "Craig", "" ], [ "Morin", "Samuel", "" ], [ "Chebotko", "Artem", "" ], [ "Abraham", "John", "" ], [ "Brazier", "Pearl", "" ] ]
TITLE: Distributed Semantic Web Data Management in HBase and MySQL Cluster ABSTRACT: Various computing and data resources on the Web are being enhanced with machine-interpretable semantic descriptions to facilitate better search, discovery and integration. This interconnected metadata constitutes the Semantic Web, whose volume can potentially grow the scale of the Web. Efficient management of Semantic Web data, expressed using the W3C's Resource Description Framework (RDF), is crucial for supporting new data-intensive, semantics-enabled applications. In this work, we study and compare two approaches to distributed RDF data management based on emerging cloud computing technologies and traditional relational database clustering technologies. In particular, we design distributed RDF data storage and querying schemes for HBase and MySQL Cluster and conduct an empirical comparison of these approaches on a cluster of commodity machines using datasets and queries from the Third Provenance Challenge and Lehigh University Benchmark. Our study reveals interesting patterns in query evaluation, shows that our algorithms are promising, and suggests that cloud computing has a great potential for scalable Semantic Web data management.
no_new_dataset
0.947914
1207.3285
Sarvesh Nikumbh
Sarvesh Nikumbh, Shameek Ghosh, Valadi Jayaraman
Biogeography-Based Informative Gene Selection and Cancer Classification Using SVM and Random Forests
6 pages; Author's copy; Presented at the IEEE World Congress on Computational Intelligence (at IEEE Congress on Evolutionary Computation), Brisbane, Australia, June 2012
null
10.1109/CEC.2012.6256127
CMS-TR-20120509
cs.NE stat.ML
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Microarray cancer gene expression data comprise of very high dimensions. Reducing the dimensions helps in improving the overall analysis and classification performance. We propose two hybrid techniques, Biogeography - based Optimization - Random Forests (BBO - RF) and BBO - SVM (Support Vector Machines) with gene ranking as a heuristic, for microarray gene expression analysis. This heuristic is obtained from information gain filter ranking procedure. The BBO algorithm generates a population of candidate subset of genes, as part of an ecosystem of habitats, and employs the migration and mutation processes across multiple generations of the population to improve the classification accuracy. The fitness of each gene subset is assessed by the classifiers - SVM and Random Forests. The performances of these hybrid techniques are evaluated on three cancer gene expression datasets retrieved from the Kent Ridge Biomedical datasets collection and the libSVM data repository. Our results demonstrate that genes selected by the proposed techniques yield classification accuracies comparable to previously reported algorithms.
[ { "version": "v1", "created": "Thu, 12 Jul 2012 19:00:46 GMT" } ]
2016-11-18T00:00:00
[ [ "Nikumbh", "Sarvesh", "" ], [ "Ghosh", "Shameek", "" ], [ "Jayaraman", "Valadi", "" ] ]
TITLE: Biogeography-Based Informative Gene Selection and Cancer Classification Using SVM and Random Forests ABSTRACT: Microarray cancer gene expression data comprise of very high dimensions. Reducing the dimensions helps in improving the overall analysis and classification performance. We propose two hybrid techniques, Biogeography - based Optimization - Random Forests (BBO - RF) and BBO - SVM (Support Vector Machines) with gene ranking as a heuristic, for microarray gene expression analysis. This heuristic is obtained from information gain filter ranking procedure. The BBO algorithm generates a population of candidate subset of genes, as part of an ecosystem of habitats, and employs the migration and mutation processes across multiple generations of the population to improve the classification accuracy. The fitness of each gene subset is assessed by the classifiers - SVM and Random Forests. The performances of these hybrid techniques are evaluated on three cancer gene expression datasets retrieved from the Kent Ridge Biomedical datasets collection and the libSVM data repository. Our results demonstrate that genes selected by the proposed techniques yield classification accuracies comparable to previously reported algorithms.
no_new_dataset
0.955693
1210.4211
Wei Lu
Wei Lu, Laks V.S. Lakshmanan
Profit Maximization over Social Networks
19 pages, 8 figures. An abbreviated version appears in 2012 IEEE International Conference on Data Mining (ICDM'12). The second version includes some minor fixes
null
10.1109/ICDM.2012.145
null
cs.SI cs.GT physics.soc-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Influence maximization is the problem of finding a set of influential users in a social network such that the expected spread of influence under a certain propagation model is maximized. Much of the previous work has neglected the important distinction between social influence and actual product adoption. However, as recognized in the management science literature, an individual who gets influenced by social acquaintances may not necessarily adopt a product (or technology), due, e.g., to monetary concerns. In this work, we distinguish between influence and adoption by explicitly modeling the states of being influenced and of adopting a product. We extend the classical Linear Threshold (LT) model to incorporate prices and valuations, and factor them into users' decision-making process of adopting a product. We show that the expected profit function under our proposed model maintains submodularity under certain conditions, but no longer exhibits monotonicity, unlike the expected influence spread function. To maximize the expected profit under our extended LT model, we employ an unbudgeted greedy framework to propose three profit maximization algorithms. The results of our detailed experimental study on three real-world datasets demonstrate that of the three algorithms, \textsf{PAGE}, which assigns prices dynamically based on the profit potential of each candidate seed, has the best performance both in the expected profit achieved and in running time.
[ { "version": "v1", "created": "Mon, 15 Oct 2012 22:32:37 GMT" }, { "version": "v2", "created": "Wed, 5 Jun 2013 16:41:04 GMT" } ]
2016-11-18T00:00:00
[ [ "Lu", "Wei", "" ], [ "Lakshmanan", "Laks V. S.", "" ] ]
TITLE: Profit Maximization over Social Networks ABSTRACT: Influence maximization is the problem of finding a set of influential users in a social network such that the expected spread of influence under a certain propagation model is maximized. Much of the previous work has neglected the important distinction between social influence and actual product adoption. However, as recognized in the management science literature, an individual who gets influenced by social acquaintances may not necessarily adopt a product (or technology), due, e.g., to monetary concerns. In this work, we distinguish between influence and adoption by explicitly modeling the states of being influenced and of adopting a product. We extend the classical Linear Threshold (LT) model to incorporate prices and valuations, and factor them into users' decision-making process of adopting a product. We show that the expected profit function under our proposed model maintains submodularity under certain conditions, but no longer exhibits monotonicity, unlike the expected influence spread function. To maximize the expected profit under our extended LT model, we employ an unbudgeted greedy framework to propose three profit maximization algorithms. The results of our detailed experimental study on three real-world datasets demonstrate that of the three algorithms, \textsf{PAGE}, which assigns prices dynamically based on the profit potential of each candidate seed, has the best performance both in the expected profit achieved and in running time.
no_new_dataset
0.947235
1308.2565
Chlo\"e Brown
Chlo\"e Brown, Anastasios Noulas, Cecilia Mascolo, Vincent Blondel
A place-focused model for social networks in cities
13 pages, 7 figures. IEEE/ASE SocialCom 2013
null
10.1109/SocialCom.2013.18
null
cs.SI physics.soc-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The focused organization theory of social ties proposes that the structure of human social networks can be arranged around extra-network foci, which can include shared physical spaces such as homes, workplaces, restaurants, and so on. Until now, this has been difficult to investigate on a large scale, but the huge volume of data available from online location-based social services now makes it possible to examine the friendships and mobility of many thousands of people, and to investigate the relationship between meetings at places and the structure of the social network. In this paper, we analyze a large dataset from Foursquare, the most popular online location-based social network. We examine the properties of city-based social networks, finding that they have common structural properties, and that the category of place where two people meet has very strong influence on the likelihood of their being friends. Inspired by these observations in combination with the focused organization theory, we then present a model to generate city-level social networks, and show that it produces networks with the structural properties seen in empirical data.
[ { "version": "v1", "created": "Mon, 12 Aug 2013 13:58:15 GMT" } ]
2016-11-18T00:00:00
[ [ "Brown", "Chloë", "" ], [ "Noulas", "Anastasios", "" ], [ "Mascolo", "Cecilia", "" ], [ "Blondel", "Vincent", "" ] ]
TITLE: A place-focused model for social networks in cities ABSTRACT: The focused organization theory of social ties proposes that the structure of human social networks can be arranged around extra-network foci, which can include shared physical spaces such as homes, workplaces, restaurants, and so on. Until now, this has been difficult to investigate on a large scale, but the huge volume of data available from online location-based social services now makes it possible to examine the friendships and mobility of many thousands of people, and to investigate the relationship between meetings at places and the structure of the social network. In this paper, we analyze a large dataset from Foursquare, the most popular online location-based social network. We examine the properties of city-based social networks, finding that they have common structural properties, and that the category of place where two people meet has very strong influence on the likelihood of their being friends. Inspired by these observations in combination with the focused organization theory, we then present a model to generate city-level social networks, and show that it produces networks with the structural properties seen in empirical data.
no_new_dataset
0.953966
1309.3908
Marco Guerini
Marco Guerini, Jacopo Staiano, Davide Albanese
Exploring Image Virality in Google Plus
8 pages, 8 figures. IEEE/ASE SocialCom 2013
null
10.1109/SocialCom.2013.101
null
cs.SI cs.CY cs.MM physics.soc-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Reactions to posts in an online social network show different dynamics depending on several textual features of the corresponding content. Do similar dynamics exist when images are posted? Exploiting a novel dataset of posts, gathered from the most popular Google+ users, we try to give an answer to such a question. We describe several virality phenomena that emerge when taking into account visual characteristics of images (such as orientation, mean saturation, etc.). We also provide hypotheses and potential explanations for the dynamics behind them, and include cases for which common-sense expectations do not hold true in our experiments.
[ { "version": "v1", "created": "Mon, 16 Sep 2013 11:35:19 GMT" } ]
2016-11-18T00:00:00
[ [ "Guerini", "Marco", "" ], [ "Staiano", "Jacopo", "" ], [ "Albanese", "Davide", "" ] ]
TITLE: Exploring Image Virality in Google Plus ABSTRACT: Reactions to posts in an online social network show different dynamics depending on several textual features of the corresponding content. Do similar dynamics exist when images are posted? Exploiting a novel dataset of posts, gathered from the most popular Google+ users, we try to give an answer to such a question. We describe several virality phenomena that emerge when taking into account visual characteristics of images (such as orientation, mean saturation, etc.). We also provide hypotheses and potential explanations for the dynamics behind them, and include cases for which common-sense expectations do not hold true in our experiments.
new_dataset
0.951863
1402.2699
Neil Zhenqiang Gong
Neil Zhenqiang Gong, Di Wang
On the Security of Trustee-based Social Authentications
13 pages. Accepted by IEEE Transactions on Information Forensics and Security
null
10.1109/TIFS.2014.2330311
null
cs.CR cs.SI
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Recently, authenticating users with the help of their friends (i.e., trustee-based social authentication) has been shown to be a promising backup authentication mechanism. A user in this system is associated with a few trustees that were selected from the user's friends. When the user wants to regain access to the account, the service provider sends different verification codes to the user's trustees. The user must obtain at least k (i.e., recovery threshold) verification codes from the trustees before being directed to reset his or her password. In this paper, we provide the first systematic study about the security of trustee-based social authentications. Specifically, we first introduce a novel framework of attacks, which we call forest fire attacks. In these attacks, an attacker initially obtains a small number of compromised users, and then the attacker iteratively attacks the rest of users by exploiting trustee-based social authentications. Then, we construct a probabilistic model to formalize the threats of forest fire attacks and their costs for attackers. Moreover, we introduce various defense strategies. Finally, we apply our framework to extensively evaluate various concrete attack and defense strategies using three real-world social network datasets. Our results have strong implications for the design of more secure trustee-based social authentications.
[ { "version": "v1", "created": "Wed, 12 Feb 2014 00:10:59 GMT" }, { "version": "v2", "created": "Thu, 20 Feb 2014 23:31:41 GMT" }, { "version": "v3", "created": "Sun, 16 Mar 2014 02:56:04 GMT" }, { "version": "v4", "created": "Sun, 8 Jun 2014 00:26:55 GMT" } ]
2016-11-18T00:00:00
[ [ "Gong", "Neil Zhenqiang", "" ], [ "Wang", "Di", "" ] ]
TITLE: On the Security of Trustee-based Social Authentications ABSTRACT: Recently, authenticating users with the help of their friends (i.e., trustee-based social authentication) has been shown to be a promising backup authentication mechanism. A user in this system is associated with a few trustees that were selected from the user's friends. When the user wants to regain access to the account, the service provider sends different verification codes to the user's trustees. The user must obtain at least k (i.e., recovery threshold) verification codes from the trustees before being directed to reset his or her password. In this paper, we provide the first systematic study about the security of trustee-based social authentications. Specifically, we first introduce a novel framework of attacks, which we call forest fire attacks. In these attacks, an attacker initially obtains a small number of compromised users, and then the attacker iteratively attacks the rest of users by exploiting trustee-based social authentications. Then, we construct a probabilistic model to formalize the threats of forest fire attacks and their costs for attackers. Moreover, we introduce various defense strategies. Finally, we apply our framework to extensively evaluate various concrete attack and defense strategies using three real-world social network datasets. Our results have strong implications for the design of more secure trustee-based social authentications.
no_new_dataset
0.939471
1406.4729
Kaiming He
Kaiming He, Xiangyu Zhang, Shaoqing Ren, Jian Sun
Spatial Pyramid Pooling in Deep Convolutional Networks for Visual Recognition
This manuscript is the accepted version for IEEE Transactions on Pattern Analysis and Machine Intelligence (TPAMI) 2015. See Changelog
null
10.1007/978-3-319-10578-9_23
null
cs.CV
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Existing deep convolutional neural networks (CNNs) require a fixed-size (e.g., 224x224) input image. This requirement is "artificial" and may reduce the recognition accuracy for the images or sub-images of an arbitrary size/scale. In this work, we equip the networks with another pooling strategy, "spatial pyramid pooling", to eliminate the above requirement. The new network structure, called SPP-net, can generate a fixed-length representation regardless of image size/scale. Pyramid pooling is also robust to object deformations. With these advantages, SPP-net should in general improve all CNN-based image classification methods. On the ImageNet 2012 dataset, we demonstrate that SPP-net boosts the accuracy of a variety of CNN architectures despite their different designs. On the Pascal VOC 2007 and Caltech101 datasets, SPP-net achieves state-of-the-art classification results using a single full-image representation and no fine-tuning. The power of SPP-net is also significant in object detection. Using SPP-net, we compute the feature maps from the entire image only once, and then pool features in arbitrary regions (sub-images) to generate fixed-length representations for training the detectors. This method avoids repeatedly computing the convolutional features. In processing test images, our method is 24-102x faster than the R-CNN method, while achieving better or comparable accuracy on Pascal VOC 2007. In ImageNet Large Scale Visual Recognition Challenge (ILSVRC) 2014, our methods rank #2 in object detection and #3 in image classification among all 38 teams. This manuscript also introduces the improvement made for this competition.
[ { "version": "v1", "created": "Wed, 18 Jun 2014 14:24:17 GMT" }, { "version": "v2", "created": "Fri, 29 Aug 2014 10:28:55 GMT" }, { "version": "v3", "created": "Tue, 6 Jan 2015 07:16:54 GMT" }, { "version": "v4", "created": "Thu, 23 Apr 2015 07:33:24 GMT" } ]
2016-11-18T00:00:00
[ [ "He", "Kaiming", "" ], [ "Zhang", "Xiangyu", "" ], [ "Ren", "Shaoqing", "" ], [ "Sun", "Jian", "" ] ]
TITLE: Spatial Pyramid Pooling in Deep Convolutional Networks for Visual Recognition ABSTRACT: Existing deep convolutional neural networks (CNNs) require a fixed-size (e.g., 224x224) input image. This requirement is "artificial" and may reduce the recognition accuracy for the images or sub-images of an arbitrary size/scale. In this work, we equip the networks with another pooling strategy, "spatial pyramid pooling", to eliminate the above requirement. The new network structure, called SPP-net, can generate a fixed-length representation regardless of image size/scale. Pyramid pooling is also robust to object deformations. With these advantages, SPP-net should in general improve all CNN-based image classification methods. On the ImageNet 2012 dataset, we demonstrate that SPP-net boosts the accuracy of a variety of CNN architectures despite their different designs. On the Pascal VOC 2007 and Caltech101 datasets, SPP-net achieves state-of-the-art classification results using a single full-image representation and no fine-tuning. The power of SPP-net is also significant in object detection. Using SPP-net, we compute the feature maps from the entire image only once, and then pool features in arbitrary regions (sub-images) to generate fixed-length representations for training the detectors. This method avoids repeatedly computing the convolutional features. In processing test images, our method is 24-102x faster than the R-CNN method, while achieving better or comparable accuracy on Pascal VOC 2007. In ImageNet Large Scale Visual Recognition Challenge (ILSVRC) 2014, our methods rank #2 in object detection and #3 in image classification among all 38 teams. This manuscript also introduces the improvement made for this competition.
no_new_dataset
0.949716
1410.2707
Giovanni Caudullo
Giovanni Caudullo
Applying Geospatial Semantic Array Programming for a Reproducible Set of Bioclimatic Indices in Europe
10 pages, 4 figures, 1 table, published in IEEE Earthzine 2014 Vol. 7 Issue 2, 877975+ 2nd quarter theme. Geospatial Semantic Array Programming. Available: http://www.earthzine.org/?p=877975
IEEE Earthzine, vol. 7, no. 2, pp. 877 975+, 2014
10.1101/009589
null
cs.CE physics.ao-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Bioclimate-driven regression analysis is a widely used approach for modelling ecological niches and zonation. Although the bioclimatic complexity of the European continent is high, a particular combination of 12 climatic and topographic covariates was recently found able to reliably reproduce the ecological zoning of the Food and Agriculture Organization of the United Nations (FAO) for forest resources assessment at pan-European scale, generating the first fuzzy similarity map of FAO ecozones in Europe. The reproducible procedure followed to derive this collection of bioclimatic indices is now presented. It required an integration of data-transformation modules (D-TM) using geospatial tools such as Geographic Information System (GIS) software, and array-based mathematical implementation such as semantic array programming (SemAP). Base variables, intermediate and final covariates are described and semantically defined by providing the workflow of D-TMs and the mathematical formulation following the SemAP notation. Source layers to derive base variables were extracted by exclusively relying on global-scale public open geodata in order for the same set of bioclimatic covariates to be reproducible in any region worldwide. In particular, two freely available datasets were exploited for temperature and precipitation (WorldClim) and elevation (Global Multi-resolution Terrain Elevation Data). The working extent covers the European continent to the Urals with a resolution of 30 arc-second. The proposed set of bioclimatic covariates will be made available as open data in the European Forest Data Centre (EFDAC). The forthcoming complete set of D-TM codelets will enable the 12 covariates to be easily reproduced and expanded through free software.
[ { "version": "v1", "created": "Fri, 10 Oct 2014 08:20:10 GMT" } ]
2016-11-18T00:00:00
[ [ "Caudullo", "Giovanni", "" ] ]
TITLE: Applying Geospatial Semantic Array Programming for a Reproducible Set of Bioclimatic Indices in Europe ABSTRACT: Bioclimate-driven regression analysis is a widely used approach for modelling ecological niches and zonation. Although the bioclimatic complexity of the European continent is high, a particular combination of 12 climatic and topographic covariates was recently found able to reliably reproduce the ecological zoning of the Food and Agriculture Organization of the United Nations (FAO) for forest resources assessment at pan-European scale, generating the first fuzzy similarity map of FAO ecozones in Europe. The reproducible procedure followed to derive this collection of bioclimatic indices is now presented. It required an integration of data-transformation modules (D-TM) using geospatial tools such as Geographic Information System (GIS) software, and array-based mathematical implementation such as semantic array programming (SemAP). Base variables, intermediate and final covariates are described and semantically defined by providing the workflow of D-TMs and the mathematical formulation following the SemAP notation. Source layers to derive base variables were extracted by exclusively relying on global-scale public open geodata in order for the same set of bioclimatic covariates to be reproducible in any region worldwide. In particular, two freely available datasets were exploited for temperature and precipitation (WorldClim) and elevation (Global Multi-resolution Terrain Elevation Data). The working extent covers the European continent to the Urals with a resolution of 30 arc-second. The proposed set of bioclimatic covariates will be made available as open data in the European Forest Data Centre (EFDAC). The forthcoming complete set of D-TM codelets will enable the 12 covariates to be easily reproduced and expanded through free software.
no_new_dataset
0.956715
1502.06105
Taehoon Lee
Taehoon Lee, Taesup Moon, Seung Jean Kim, Sungroh Yoon
Regularization and Kernelization of the Maximin Correlation Approach
Submitted to IEEE Access
null
10.1109/ACCESS.2016.2551727
null
cs.CV cs.LG
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Robust classification becomes challenging when each class consists of multiple subclasses. Examples include multi-font optical character recognition and automated protein function prediction. In correlation-based nearest-neighbor classification, the maximin correlation approach (MCA) provides the worst-case optimal solution by minimizing the maximum misclassification risk through an iterative procedure. Despite the optimality, the original MCA has drawbacks that have limited its wide applicability in practice. That is, the MCA tends to be sensitive to outliers, cannot effectively handle nonlinearities in datasets, and suffers from having high computational complexity. To address these limitations, we propose an improved solution, named regularized maximin correlation approach (R-MCA). We first reformulate MCA as a quadratically constrained linear programming (QCLP) problem, incorporate regularization by introducing slack variables in the primal problem of the QCLP, and derive the corresponding Lagrangian dual. The dual formulation enables us to apply the kernel trick to R-MCA so that it can better handle nonlinearities. Our experimental results demonstrate that the regularization and kernelization make the proposed R-MCA more robust and accurate for various classification tasks than the original MCA. Furthermore, when the data size or dimensionality grows, R-MCA runs substantially faster by solving either the primal or dual (whichever has a smaller variable dimension) of the QCLP.
[ { "version": "v1", "created": "Sat, 21 Feb 2015 14:37:44 GMT" }, { "version": "v2", "created": "Tue, 29 Mar 2016 04:42:12 GMT" } ]
2016-11-18T00:00:00
[ [ "Lee", "Taehoon", "" ], [ "Moon", "Taesup", "" ], [ "Kim", "Seung Jean", "" ], [ "Yoon", "Sungroh", "" ] ]
TITLE: Regularization and Kernelization of the Maximin Correlation Approach ABSTRACT: Robust classification becomes challenging when each class consists of multiple subclasses. Examples include multi-font optical character recognition and automated protein function prediction. In correlation-based nearest-neighbor classification, the maximin correlation approach (MCA) provides the worst-case optimal solution by minimizing the maximum misclassification risk through an iterative procedure. Despite the optimality, the original MCA has drawbacks that have limited its wide applicability in practice. That is, the MCA tends to be sensitive to outliers, cannot effectively handle nonlinearities in datasets, and suffers from having high computational complexity. To address these limitations, we propose an improved solution, named regularized maximin correlation approach (R-MCA). We first reformulate MCA as a quadratically constrained linear programming (QCLP) problem, incorporate regularization by introducing slack variables in the primal problem of the QCLP, and derive the corresponding Lagrangian dual. The dual formulation enables us to apply the kernel trick to R-MCA so that it can better handle nonlinearities. Our experimental results demonstrate that the regularization and kernelization make the proposed R-MCA more robust and accurate for various classification tasks than the original MCA. Furthermore, when the data size or dimensionality grows, R-MCA runs substantially faster by solving either the primal or dual (whichever has a smaller variable dimension) of the QCLP.
no_new_dataset
0.947575
1502.07226
Haifeng Wang
Haifeng Wang, R. Todd Constable and Gigi Galiana
Accelerate Single-shot Data Acquisitions Using Compressed Sensing and FRONSAC Imaging
4 pages, 4 figures, accepted to IEEE International Symposium on Biomedical Imaging (ISBI) 2015
null
10.1109/ISBI.2015.7164101
null
physics.med-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Nonlinear spatial encoding magnetic (SEM) fields have been studied to complement multichannel RF encoding and accelerate MRI scans. Published schemes include PatLoc, O-Space, Null Space, 4D-RIO, and others, but the large variety of possible approaches to exploiting nonlinear SEMs remains mostly unexplored. Before, we have presented a new approach, Fast ROtary Nonlinear Spatial ACquisition (FRONSAC) imaging, where the nonlinear fields provide a small rotating perturbation to standard linear trajectories. While FRONSAC encoding greatly improves image quality, at the highest accelerations or weakest FRONSAC fields, some undersampling artifacts remain. However, the under-sampling artifacts that occur with FRONSAC encoding are relatively incoherent and well suited to the compressed sensing (CS) reconstruction. CS provides a sparsity-promoting convex strategy to reconstruct images from highly undersampled datasets. The work presented here combines the benefits of FRONSAC and CS. Simulations illustrate that this combination can further improve image reconstruction with FRONSAC gradients of low amplitudes and frequencies.
[ { "version": "v1", "created": "Wed, 25 Feb 2015 16:21:23 GMT" }, { "version": "v2", "created": "Mon, 20 Apr 2015 20:42:19 GMT" }, { "version": "v3", "created": "Fri, 24 Apr 2015 20:43:45 GMT" } ]
2016-11-18T00:00:00
[ [ "Wang", "Haifeng", "" ], [ "Constable", "R. Todd", "" ], [ "Galiana", "Gigi", "" ] ]
TITLE: Accelerate Single-shot Data Acquisitions Using Compressed Sensing and FRONSAC Imaging ABSTRACT: Nonlinear spatial encoding magnetic (SEM) fields have been studied to complement multichannel RF encoding and accelerate MRI scans. Published schemes include PatLoc, O-Space, Null Space, 4D-RIO, and others, but the large variety of possible approaches to exploiting nonlinear SEMs remains mostly unexplored. Before, we have presented a new approach, Fast ROtary Nonlinear Spatial ACquisition (FRONSAC) imaging, where the nonlinear fields provide a small rotating perturbation to standard linear trajectories. While FRONSAC encoding greatly improves image quality, at the highest accelerations or weakest FRONSAC fields, some undersampling artifacts remain. However, the under-sampling artifacts that occur with FRONSAC encoding are relatively incoherent and well suited to the compressed sensing (CS) reconstruction. CS provides a sparsity-promoting convex strategy to reconstruct images from highly undersampled datasets. The work presented here combines the benefits of FRONSAC and CS. Simulations illustrate that this combination can further improve image reconstruction with FRONSAC gradients of low amplitudes and frequencies.
no_new_dataset
0.948251
1503.00759
Maximilian Nickel
Maximilian Nickel, Kevin Murphy, Volker Tresp, Evgeniy Gabrilovich
A Review of Relational Machine Learning for Knowledge Graphs
To appear in Proceedings of the IEEE
null
10.1109/JPROC.2015.2483592
null
stat.ML cs.LG
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Relational machine learning studies methods for the statistical analysis of relational, or graph-structured, data. In this paper, we provide a review of how such statistical models can be "trained" on large knowledge graphs, and then used to predict new facts about the world (which is equivalent to predicting new edges in the graph). In particular, we discuss two fundamentally different kinds of statistical relational models, both of which can scale to massive datasets. The first is based on latent feature models such as tensor factorization and multiway neural networks. The second is based on mining observable patterns in the graph. We also show how to combine these latent and observable models to get improved modeling power at decreased computational cost. Finally, we discuss how such statistical models of graphs can be combined with text-based information extraction methods for automatically constructing knowledge graphs from the Web. To this end, we also discuss Google's Knowledge Vault project as an example of such combination.
[ { "version": "v1", "created": "Mon, 2 Mar 2015 21:35:41 GMT" }, { "version": "v2", "created": "Wed, 26 Aug 2015 16:35:31 GMT" }, { "version": "v3", "created": "Mon, 28 Sep 2015 17:40:35 GMT" } ]
2016-11-18T00:00:00
[ [ "Nickel", "Maximilian", "" ], [ "Murphy", "Kevin", "" ], [ "Tresp", "Volker", "" ], [ "Gabrilovich", "Evgeniy", "" ] ]
TITLE: A Review of Relational Machine Learning for Knowledge Graphs ABSTRACT: Relational machine learning studies methods for the statistical analysis of relational, or graph-structured, data. In this paper, we provide a review of how such statistical models can be "trained" on large knowledge graphs, and then used to predict new facts about the world (which is equivalent to predicting new edges in the graph). In particular, we discuss two fundamentally different kinds of statistical relational models, both of which can scale to massive datasets. The first is based on latent feature models such as tensor factorization and multiway neural networks. The second is based on mining observable patterns in the graph. We also show how to combine these latent and observable models to get improved modeling power at decreased computational cost. Finally, we discuss how such statistical models of graphs can be combined with text-based information extraction methods for automatically constructing knowledge graphs from the Web. To this end, we also discuss Google's Knowledge Vault project as an example of such combination.
no_new_dataset
0.950503
1503.03832
Florian Schroff
Florian Schroff, Dmitry Kalenichenko, James Philbin
FaceNet: A Unified Embedding for Face Recognition and Clustering
Also published, in Proceedings of the IEEE Computer Society Conference on Computer Vision and Pattern Recognition 2015
null
10.1109/CVPR.2015.7298682
null
cs.CV
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Despite significant recent advances in the field of face recognition, implementing face verification and recognition efficiently at scale presents serious challenges to current approaches. In this paper we present a system, called FaceNet, that directly learns a mapping from face images to a compact Euclidean space where distances directly correspond to a measure of face similarity. Once this space has been produced, tasks such as face recognition, verification and clustering can be easily implemented using standard techniques with FaceNet embeddings as feature vectors. Our method uses a deep convolutional network trained to directly optimize the embedding itself, rather than an intermediate bottleneck layer as in previous deep learning approaches. To train, we use triplets of roughly aligned matching / non-matching face patches generated using a novel online triplet mining method. The benefit of our approach is much greater representational efficiency: we achieve state-of-the-art face recognition performance using only 128-bytes per face. On the widely used Labeled Faces in the Wild (LFW) dataset, our system achieves a new record accuracy of 99.63%. On YouTube Faces DB it achieves 95.12%. Our system cuts the error rate in comparison to the best published result by 30% on both datasets. We also introduce the concept of harmonic embeddings, and a harmonic triplet loss, which describe different versions of face embeddings (produced by different networks) that are compatible to each other and allow for direct comparison between each other.
[ { "version": "v1", "created": "Thu, 12 Mar 2015 18:10:53 GMT" }, { "version": "v2", "created": "Thu, 4 Jun 2015 19:17:30 GMT" }, { "version": "v3", "created": "Wed, 17 Jun 2015 23:35:47 GMT" } ]
2016-11-18T00:00:00
[ [ "Schroff", "Florian", "" ], [ "Kalenichenko", "Dmitry", "" ], [ "Philbin", "James", "" ] ]
TITLE: FaceNet: A Unified Embedding for Face Recognition and Clustering ABSTRACT: Despite significant recent advances in the field of face recognition, implementing face verification and recognition efficiently at scale presents serious challenges to current approaches. In this paper we present a system, called FaceNet, that directly learns a mapping from face images to a compact Euclidean space where distances directly correspond to a measure of face similarity. Once this space has been produced, tasks such as face recognition, verification and clustering can be easily implemented using standard techniques with FaceNet embeddings as feature vectors. Our method uses a deep convolutional network trained to directly optimize the embedding itself, rather than an intermediate bottleneck layer as in previous deep learning approaches. To train, we use triplets of roughly aligned matching / non-matching face patches generated using a novel online triplet mining method. The benefit of our approach is much greater representational efficiency: we achieve state-of-the-art face recognition performance using only 128-bytes per face. On the widely used Labeled Faces in the Wild (LFW) dataset, our system achieves a new record accuracy of 99.63%. On YouTube Faces DB it achieves 95.12%. Our system cuts the error rate in comparison to the best published result by 30% on both datasets. We also introduce the concept of harmonic embeddings, and a harmonic triplet loss, which describe different versions of face embeddings (produced by different networks) that are compatible to each other and allow for direct comparison between each other.
no_new_dataset
0.950503
1503.04877
Syed Agha Muhammad
Syed Agha Muhammad and Kristof Van Laerhoven
An Automated System for Discovering Neighborhood Patterns in Ego Networks
null
null
null
null
cs.SI physics.soc-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Generally, social network analysis has often focused on the topology of the network without considering the characteristics of individuals involved in them. Less attention is given to study the behavior of individuals, considering they are the basic entity of a graph. Given a mobile social network graph, what are good features to extract key information from the nodes? How many distinct neighborhood patterns exist for ego nodes? What clues does such information provide to study nodes over a long period of time? In this report, we develop an automated system in order to discover the occurrences of prototypical ego-centric patterns from data. We aim to provide a data-driven instrument to be used in behavioral sciences for graph interpretations. We analyze social networks derived from real-world data collected with smart-phones. We select 13 well-known network measures, especially those concerned with ego graphs. We form eight feature subsets and then assess their performance using unsupervised clustering techniques to discover distinguishing ego-centric patterns. From clustering analysis, we discover that eight distinct neighborhood patterns have emerged. This categorization allows concise analysis of users' data as they change over time. The results provide a fine-grained analysis for the contribution of different feature sets to detect unique clustering patterns. Last, as a case study, two datasets are studied over long periods to demonstrate the utility of this method. The study shows the effectiveness of the proposed approach in discovering important trends from data.
[ { "version": "v1", "created": "Mon, 16 Mar 2015 23:07:12 GMT" } ]
2016-11-18T00:00:00
[ [ "Muhammad", "Syed Agha", "" ], [ "Van Laerhoven", "Kristof", "" ] ]
TITLE: An Automated System for Discovering Neighborhood Patterns in Ego Networks ABSTRACT: Generally, social network analysis has often focused on the topology of the network without considering the characteristics of individuals involved in them. Less attention is given to study the behavior of individuals, considering they are the basic entity of a graph. Given a mobile social network graph, what are good features to extract key information from the nodes? How many distinct neighborhood patterns exist for ego nodes? What clues does such information provide to study nodes over a long period of time? In this report, we develop an automated system in order to discover the occurrences of prototypical ego-centric patterns from data. We aim to provide a data-driven instrument to be used in behavioral sciences for graph interpretations. We analyze social networks derived from real-world data collected with smart-phones. We select 13 well-known network measures, especially those concerned with ego graphs. We form eight feature subsets and then assess their performance using unsupervised clustering techniques to discover distinguishing ego-centric patterns. From clustering analysis, we discover that eight distinct neighborhood patterns have emerged. This categorization allows concise analysis of users' data as they change over time. The results provide a fine-grained analysis for the contribution of different feature sets to detect unique clustering patterns. Last, as a case study, two datasets are studied over long periods to demonstrate the utility of this method. The study shows the effectiveness of the proposed approach in discovering important trends from data.
no_new_dataset
0.9462
1503.08771
Jinxue Zhang
Jinxue Zhang, Jingchao Sun, Rui Zhang, Yanchao Zhang
Your Actions Tell Where You Are: Uncovering Twitter Users in a Metropolitan Area
Accepted by IEEE Conference on Communications and Network Security (CNS) 2015
null
10.1109/CNS.2015.7346854
null
cs.SI
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Twitter is an extremely popular social networking platform. Most Twitter users do not disclose their locations due to privacy concerns. Although inferring the location of an individual Twitter user has been extensively studied, it is still missing to effectively find the majority of the users in a specific geographical area without scanning the whole Twittersphere, and obtaining these users will result in both positive and negative significance. In this paper, we propose LocInfer, a novel and lightweight system to tackle this problem. LocInfer explores the fact that user communications in Twitter exhibit strong geographic locality, which we validate through large-scale datasets. Based on the experiments from four representative metropolitan areas in U.S., LocInfer can discover on average 86.6% of the users with 73.2% accuracy in each area by only checking a small set of candidate users. We also present a countermeasure to the users highly sensitive to location privacy and show its efficacy by simulations.
[ { "version": "v1", "created": "Mon, 30 Mar 2015 18:07:30 GMT" }, { "version": "v2", "created": "Mon, 3 Aug 2015 23:46:19 GMT" } ]
2016-11-18T00:00:00
[ [ "Zhang", "Jinxue", "" ], [ "Sun", "Jingchao", "" ], [ "Zhang", "Rui", "" ], [ "Zhang", "Yanchao", "" ] ]
TITLE: Your Actions Tell Where You Are: Uncovering Twitter Users in a Metropolitan Area ABSTRACT: Twitter is an extremely popular social networking platform. Most Twitter users do not disclose their locations due to privacy concerns. Although inferring the location of an individual Twitter user has been extensively studied, it is still missing to effectively find the majority of the users in a specific geographical area without scanning the whole Twittersphere, and obtaining these users will result in both positive and negative significance. In this paper, we propose LocInfer, a novel and lightweight system to tackle this problem. LocInfer explores the fact that user communications in Twitter exhibit strong geographic locality, which we validate through large-scale datasets. Based on the experiments from four representative metropolitan areas in U.S., LocInfer can discover on average 86.6% of the users with 73.2% accuracy in each area by only checking a small set of candidate users. We also present a countermeasure to the users highly sensitive to location privacy and show its efficacy by simulations.
no_new_dataset
0.946941
1504.03573
Marcus A. Brubaker
Marcus A. Brubaker, Ali Punjani and David J. Fleet
Building Proteins in a Day: Efficient 3D Molecular Reconstruction
To be presented at IEEE Conference on Computer Vision and Pattern Recognition (CVPR) 2015
null
10.1109/CVPR.2015.7298929
null
cs.CV q-bio.QM
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Discovering the 3D atomic structure of molecules such as proteins and viruses is a fundamental research problem in biology and medicine. Electron Cryomicroscopy (Cryo-EM) is a promising vision-based technique for structure estimation which attempts to reconstruct 3D structures from 2D images. This paper addresses the challenging problem of 3D reconstruction from 2D Cryo-EM images. A new framework for estimation is introduced which relies on modern stochastic optimization techniques to scale to large datasets. We also introduce a novel technique which reduces the cost of evaluating the objective function during optimization by over five orders or magnitude. The net result is an approach capable of estimating 3D molecular structure from large scale datasets in about a day on a single workstation.
[ { "version": "v1", "created": "Tue, 14 Apr 2015 14:56:17 GMT" } ]
2016-11-18T00:00:00
[ [ "Brubaker", "Marcus A.", "" ], [ "Punjani", "Ali", "" ], [ "Fleet", "David J.", "" ] ]
TITLE: Building Proteins in a Day: Efficient 3D Molecular Reconstruction ABSTRACT: Discovering the 3D atomic structure of molecules such as proteins and viruses is a fundamental research problem in biology and medicine. Electron Cryomicroscopy (Cryo-EM) is a promising vision-based technique for structure estimation which attempts to reconstruct 3D structures from 2D images. This paper addresses the challenging problem of 3D reconstruction from 2D Cryo-EM images. A new framework for estimation is introduced which relies on modern stochastic optimization techniques to scale to large datasets. We also introduce a novel technique which reduces the cost of evaluating the objective function during optimization by over five orders or magnitude. The net result is an approach capable of estimating 3D molecular structure from large scale datasets in about a day on a single workstation.
no_new_dataset
0.947769
1507.06838
Modesto Castrill\'on-Santana
M. Castrill\'on-Santana, J. Lorenzo-Navarro and E. Ram\'on-Balmaseda
Descriptors and regions of interest fusion for gender classification in the wild. Comparison and combination with Convolutional Neural Networks
Revised version containing 12 pages. This revision includes newer referenes, results with CNN, fusion of local descriptors amd CNN and corrects different typos
null
10.1016/j.imavis.2016.10.004
null
cs.CV
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Gender classification (GC) has achieved high accuracy in different experimental evaluations based mostly on inner facial details. However, these results do not generalize well in unrestricted datasets and particularly in cross-database experiments, where the performance drops drastically. In this paper, we analyze the state-of-the-art GC accuracy on three large datasets: MORPH, LFW and GROUPS. We discuss their respective difficulties and bias, concluding that the most challenging and wildest complexity is present in GROUPS. This dataset covers hard conditions such as low resolution imagery and cluttered background. Firstly, we analyze in depth the performance of different descriptors extracted from the face and its local context on this dataset. Selecting the bests and studying their most suitable combination allows us to design a solution that beats any previously published results for GROUPS with the Dago's protocol, reaching an accuracy over 94.2%, reducing the gap with other simpler datasets. The chosen solution based on local descriptors is later evaluated in a cross-database scenario with the three mentioned datasets, and full dataset 5-fold cross validation. The achieved results are compared with a Convolutional Neural Network approach, achieving rather similar marks. Finally, a solution is proposed combining both focuses, exhibiting great complementarity, boosting GC performance to beat previously published results in GC both cross-database, and full in-database evaluations.
[ { "version": "v1", "created": "Fri, 24 Jul 2015 13:22:29 GMT" }, { "version": "v2", "created": "Fri, 19 Feb 2016 12:44:13 GMT" } ]
2016-11-18T00:00:00
[ [ "Castrillón-Santana", "M.", "" ], [ "Lorenzo-Navarro", "J.", "" ], [ "Ramón-Balmaseda", "E.", "" ] ]
TITLE: Descriptors and regions of interest fusion for gender classification in the wild. Comparison and combination with Convolutional Neural Networks ABSTRACT: Gender classification (GC) has achieved high accuracy in different experimental evaluations based mostly on inner facial details. However, these results do not generalize well in unrestricted datasets and particularly in cross-database experiments, where the performance drops drastically. In this paper, we analyze the state-of-the-art GC accuracy on three large datasets: MORPH, LFW and GROUPS. We discuss their respective difficulties and bias, concluding that the most challenging and wildest complexity is present in GROUPS. This dataset covers hard conditions such as low resolution imagery and cluttered background. Firstly, we analyze in depth the performance of different descriptors extracted from the face and its local context on this dataset. Selecting the bests and studying their most suitable combination allows us to design a solution that beats any previously published results for GROUPS with the Dago's protocol, reaching an accuracy over 94.2%, reducing the gap with other simpler datasets. The chosen solution based on local descriptors is later evaluated in a cross-database scenario with the three mentioned datasets, and full dataset 5-fold cross validation. The achieved results are compared with a Convolutional Neural Network approach, achieving rather similar marks. Finally, a solution is proposed combining both focuses, exhibiting great complementarity, boosting GC performance to beat previously published results in GC both cross-database, and full in-database evaluations.
no_new_dataset
0.949529
1511.04110
Ali Mollahosseini
Ali Mollahosseini, David Chan, Mohammad H. Mahoor
Going Deeper in Facial Expression Recognition using Deep Neural Networks
To be appear in IEEE Winter Conference on Applications of Computer Vision (WACV), 2016 {Accepted in first round submission}
IEEE Winter Conference on Applications of Computer Vision (WACV), 2016
10.1109/WACV.2016.7477450
null
cs.NE cs.CV
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Automated Facial Expression Recognition (FER) has remained a challenging and interesting problem. Despite efforts made in developing various methods for FER, existing approaches traditionally lack generalizability when applied to unseen images or those that are captured in wild setting. Most of the existing approaches are based on engineered features (e.g. HOG, LBPH, and Gabor) where the classifier's hyperparameters are tuned to give best recognition accuracies across a single database, or a small collection of similar databases. Nevertheless, the results are not significant when they are applied to novel data. This paper proposes a deep neural network architecture to address the FER problem across multiple well-known standard face datasets. Specifically, our network consists of two convolutional layers each followed by max pooling and then four Inception layers. The network is a single component architecture that takes registered facial images as the input and classifies them into either of the six basic or the neutral expressions. We conducted comprehensive experiments on seven publically available facial expression databases, viz. MultiPIE, MMI, CK+, DISFA, FERA, SFEW, and FER2013. The results of proposed architecture are comparable to or better than the state-of-the-art methods and better than traditional convolutional neural networks and in both accuracy and training time.
[ { "version": "v1", "created": "Thu, 12 Nov 2015 22:10:46 GMT" } ]
2016-11-18T00:00:00
[ [ "Mollahosseini", "Ali", "" ], [ "Chan", "David", "" ], [ "Mahoor", "Mohammad H.", "" ] ]
TITLE: Going Deeper in Facial Expression Recognition using Deep Neural Networks ABSTRACT: Automated Facial Expression Recognition (FER) has remained a challenging and interesting problem. Despite efforts made in developing various methods for FER, existing approaches traditionally lack generalizability when applied to unseen images or those that are captured in wild setting. Most of the existing approaches are based on engineered features (e.g. HOG, LBPH, and Gabor) where the classifier's hyperparameters are tuned to give best recognition accuracies across a single database, or a small collection of similar databases. Nevertheless, the results are not significant when they are applied to novel data. This paper proposes a deep neural network architecture to address the FER problem across multiple well-known standard face datasets. Specifically, our network consists of two convolutional layers each followed by max pooling and then four Inception layers. The network is a single component architecture that takes registered facial images as the input and classifies them into either of the six basic or the neutral expressions. We conducted comprehensive experiments on seven publically available facial expression databases, viz. MultiPIE, MMI, CK+, DISFA, FERA, SFEW, and FER2013. The results of proposed architecture are comparable to or better than the state-of-the-art methods and better than traditional convolutional neural networks and in both accuracy and training time.
no_new_dataset
0.949902
1511.04192
Tianshui Chen
Tianshui Chen, Liang Lin, Lingbo Liu, Xiaonan Luo, Xuelong Li
DISC: Deep Image Saliency Computing via Progressive Representation Learning
This manuscript is the accepted version for IEEE Transactions on Neural Networks and Learning Systems (T-NNLS), 2015
null
10.1109/TNNLS.2015.2506664
null
cs.CV
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Salient object detection increasingly receives attention as an important component or step in several pattern recognition and image processing tasks. Although a variety of powerful saliency models have been intensively proposed, they usually involve heavy feature (or model) engineering based on priors (or assumptions) about the properties of objects and backgrounds. Inspired by the effectiveness of recently developed feature learning, we provide a novel Deep Image Saliency Computing (DISC) framework for fine-grained image saliency computing. In particular, we model the image saliency from both the coarse- and fine-level observations, and utilize the deep convolutional neural network (CNN) to learn the saliency representation in a progressive manner. Specifically, our saliency model is built upon two stacked CNNs. The first CNN generates a coarse-level saliency map by taking the overall image as the input, roughly identifying saliency regions in the global context. Furthermore, we integrate superpixel-based local context information in the first CNN to refine the coarse-level saliency map. Guided by the coarse saliency map, the second CNN focuses on the local context to produce fine-grained and accurate saliency map while preserving object details. For a testing image, the two CNNs collaboratively conduct the saliency computing in one shot. Our DISC framework is capable of uniformly highlighting the objects-of-interest from complex background while preserving well object details. Extensive experiments on several standard benchmarks suggest that DISC outperforms other state-of-the-art methods and it also generalizes well across datasets without additional training. The executable version of DISC is available online: http://vision.sysu.edu.cn/projects/DISC.
[ { "version": "v1", "created": "Fri, 13 Nov 2015 07:14:13 GMT" }, { "version": "v2", "created": "Thu, 10 Dec 2015 13:11:23 GMT" } ]
2016-11-18T00:00:00
[ [ "Chen", "Tianshui", "" ], [ "Lin", "Liang", "" ], [ "Liu", "Lingbo", "" ], [ "Luo", "Xiaonan", "" ], [ "Li", "Xuelong", "" ] ]
TITLE: DISC: Deep Image Saliency Computing via Progressive Representation Learning ABSTRACT: Salient object detection increasingly receives attention as an important component or step in several pattern recognition and image processing tasks. Although a variety of powerful saliency models have been intensively proposed, they usually involve heavy feature (or model) engineering based on priors (or assumptions) about the properties of objects and backgrounds. Inspired by the effectiveness of recently developed feature learning, we provide a novel Deep Image Saliency Computing (DISC) framework for fine-grained image saliency computing. In particular, we model the image saliency from both the coarse- and fine-level observations, and utilize the deep convolutional neural network (CNN) to learn the saliency representation in a progressive manner. Specifically, our saliency model is built upon two stacked CNNs. The first CNN generates a coarse-level saliency map by taking the overall image as the input, roughly identifying saliency regions in the global context. Furthermore, we integrate superpixel-based local context information in the first CNN to refine the coarse-level saliency map. Guided by the coarse saliency map, the second CNN focuses on the local context to produce fine-grained and accurate saliency map while preserving object details. For a testing image, the two CNNs collaboratively conduct the saliency computing in one shot. Our DISC framework is capable of uniformly highlighting the objects-of-interest from complex background while preserving well object details. Extensive experiments on several standard benchmarks suggest that DISC outperforms other state-of-the-art methods and it also generalizes well across datasets without additional training. The executable version of DISC is available online: http://vision.sysu.edu.cn/projects/DISC.
no_new_dataset
0.951051
1602.06888
Maria Patterson
Maria T Patterson, Nikolas Anderson, Collin Bennett, Jacob Bruggemann, Robert Grossman, Matthew Handy, Vuong Ly, Dan Mandl, Shane Pederson, Jim Pivarski, Ray Powell, Jonathan Spring and Walt Wells
The Matsu Wheel: A Cloud-based Framework for Efficient Analysis and Reanalysis of Earth Satellite Imagery
10 pages, accepted for presentation to IEEE BigDataService 2016
null
10.1109/BigDataService.2016.39
null
cs.DC astro-ph.IM
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Project Matsu is a collaboration between the Open Commons Consortium and NASA focused on developing open source technology for the cloud-based processing of Earth satellite imagery. A particular focus is the development of applications for detecting fires and floods to help support natural disaster detection and relief. Project Matsu has developed an open source cloud-based infrastructure to process, analyze, and reanalyze large collections of hyperspectral satellite image data using OpenStack, Hadoop, MapReduce, Storm and related technologies. We describe a framework for efficient analysis of large amounts of data called the Matsu "Wheel." The Matsu Wheel is currently used to process incoming hyperspectral satellite data produced daily by NASA's Earth Observing-1 (EO-1) satellite. The framework is designed to be able to support scanning queries using cloud computing applications, such as Hadoop and Accumulo. A scanning query processes all, or most of the data, in a database or data repository. We also describe our preliminary Wheel analytics, including an anomaly detector for rare spectral signatures or thermal anomalies in hyperspectral data and a land cover classifier that can be used for water and flood detection. Each of these analytics can generate visual reports accessible via the web for the public and interested decision makers. The resultant products of the analytics are also made accessible through an Open Geospatial Compliant (OGC)-compliant Web Map Service (WMS) for further distribution. The Matsu Wheel allows many shared data services to be performed together to efficiently use resources for processing hyperspectral satellite image data and other, e.g., large environmental datasets that may be analyzed for many purposes.
[ { "version": "v1", "created": "Mon, 22 Feb 2016 18:51:14 GMT" } ]
2016-11-18T00:00:00
[ [ "Patterson", "Maria T", "" ], [ "Anderson", "Nikolas", "" ], [ "Bennett", "Collin", "" ], [ "Bruggemann", "Jacob", "" ], [ "Grossman", "Robert", "" ], [ "Handy", "Matthew", "" ], [ "Ly", "Vuong", "" ], [ "Mandl", "Dan", "" ], [ "Pederson", "Shane", "" ], [ "Pivarski", "Jim", "" ], [ "Powell", "Ray", "" ], [ "Spring", "Jonathan", "" ], [ "Wells", "Walt", "" ] ]
TITLE: The Matsu Wheel: A Cloud-based Framework for Efficient Analysis and Reanalysis of Earth Satellite Imagery ABSTRACT: Project Matsu is a collaboration between the Open Commons Consortium and NASA focused on developing open source technology for the cloud-based processing of Earth satellite imagery. A particular focus is the development of applications for detecting fires and floods to help support natural disaster detection and relief. Project Matsu has developed an open source cloud-based infrastructure to process, analyze, and reanalyze large collections of hyperspectral satellite image data using OpenStack, Hadoop, MapReduce, Storm and related technologies. We describe a framework for efficient analysis of large amounts of data called the Matsu "Wheel." The Matsu Wheel is currently used to process incoming hyperspectral satellite data produced daily by NASA's Earth Observing-1 (EO-1) satellite. The framework is designed to be able to support scanning queries using cloud computing applications, such as Hadoop and Accumulo. A scanning query processes all, or most of the data, in a database or data repository. We also describe our preliminary Wheel analytics, including an anomaly detector for rare spectral signatures or thermal anomalies in hyperspectral data and a land cover classifier that can be used for water and flood detection. Each of these analytics can generate visual reports accessible via the web for the public and interested decision makers. The resultant products of the analytics are also made accessible through an Open Geospatial Compliant (OGC)-compliant Web Map Service (WMS) for further distribution. The Matsu Wheel allows many shared data services to be performed together to efficiently use resources for processing hyperspectral satellite image data and other, e.g., large environmental datasets that may be analyzed for many purposes.
no_new_dataset
0.959269
1602.09076
Paolo Campigotto
Paolo Campigotto, Christian Rudloff, Maximilian Leodolter and Dietmar Bauer
Personalized and situation-aware multimodal route recommendations: the FAVOUR algorithm
12 pages, 6 figures, 1 table. Submitted to IEEE Transactions on Intelligent Transportation Systems journal for publication
null
10.1109/TITS.2016.2565643
null
cs.AI
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Route choice in multimodal networks shows a considerable variation between different individuals as well as the current situational context. Personalization of recommendation algorithms are already common in many areas, e.g., online retail. However, most online routing applications still provide shortest distance or shortest travel-time routes only, neglecting individual preferences as well as the current situation. Both aspects are of particular importance in a multimodal setting as attractivity of some transportation modes such as biking crucially depends on personal characteristics and exogenous factors like the weather. This paper introduces the FAVourite rOUte Recommendation (FAVOUR) approach to provide personalized, situation-aware route proposals based on three steps: first, at the initialization stage, the user provides limited information (home location, work place, mobility options, sociodemographics) used to select one out of a small number of initial profiles. Second, based on this information, a stated preference survey is designed in order to sharpen the profile. In this step a mass preference prior is used to encode the prior knowledge on preferences from the class identified in step one. And third, subsequently the profile is continuously updated during usage of the routing services. The last two steps use Bayesian learning techniques in order to incorporate information from all contributing individuals. The FAVOUR approach is presented in detail and tested on a small number of survey participants. The experimental results on this real-world dataset show that FAVOUR generates better-quality recommendations w.r.t. alternative learning algorithms from the literature. In particular the definition of the mass preference prior for initialization of step two is shown to provide better predictions than a number of alternatives from the literature.
[ { "version": "v1", "created": "Mon, 29 Feb 2016 18:16:12 GMT" } ]
2016-11-18T00:00:00
[ [ "Campigotto", "Paolo", "" ], [ "Rudloff", "Christian", "" ], [ "Leodolter", "Maximilian", "" ], [ "Bauer", "Dietmar", "" ] ]
TITLE: Personalized and situation-aware multimodal route recommendations: the FAVOUR algorithm ABSTRACT: Route choice in multimodal networks shows a considerable variation between different individuals as well as the current situational context. Personalization of recommendation algorithms are already common in many areas, e.g., online retail. However, most online routing applications still provide shortest distance or shortest travel-time routes only, neglecting individual preferences as well as the current situation. Both aspects are of particular importance in a multimodal setting as attractivity of some transportation modes such as biking crucially depends on personal characteristics and exogenous factors like the weather. This paper introduces the FAVourite rOUte Recommendation (FAVOUR) approach to provide personalized, situation-aware route proposals based on three steps: first, at the initialization stage, the user provides limited information (home location, work place, mobility options, sociodemographics) used to select one out of a small number of initial profiles. Second, based on this information, a stated preference survey is designed in order to sharpen the profile. In this step a mass preference prior is used to encode the prior knowledge on preferences from the class identified in step one. And third, subsequently the profile is continuously updated during usage of the routing services. The last two steps use Bayesian learning techniques in order to incorporate information from all contributing individuals. The FAVOUR approach is presented in detail and tested on a small number of survey participants. The experimental results on this real-world dataset show that FAVOUR generates better-quality recommendations w.r.t. alternative learning algorithms from the literature. In particular the definition of the mass preference prior for initialization of step two is shown to provide better predictions than a number of alternatives from the literature.
no_new_dataset
0.953622
1604.07807
Shangxuan Wu
Shangxuan Wu, Ying-Cong Chen, Xiang Li, An-Cong Wu, Jin-Jie You, and Wei-Shi Zheng
An Enhanced Deep Feature Representation for Person Re-identification
Citation for this paper: Shangxuan Wu, Ying-Cong Chen, Xiang Li, An-Cong Wu, Jin-Jie You, and Wei-Shi Zheng. An Enhanced Deep Feature Representation for Person Re-identification. In IEEE WACV, 2016
null
10.1109/WACV.2016.7477681
null
cs.CV
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Feature representation and metric learning are two critical components in person re-identification models. In this paper, we focus on the feature representation and claim that hand-crafted histogram features can be complementary to Convolutional Neural Network (CNN) features. We propose a novel feature extraction model called Feature Fusion Net (FFN) for pedestrian image representation. In FFN, back propagation makes CNN features constrained by the handcrafted features. Utilizing color histogram features (RGB, HSV, YCbCr, Lab and YIQ) and texture features (multi-scale and multi-orientation Gabor features), we get a new deep feature representation that is more discriminative and compact. Experiments on three challenging datasets (VIPeR, CUHK01, PRID450s) validates the effectiveness of our proposal.
[ { "version": "v1", "created": "Tue, 26 Apr 2016 19:27:50 GMT" }, { "version": "v2", "created": "Thu, 28 Apr 2016 08:17:35 GMT" } ]
2016-11-18T00:00:00
[ [ "Wu", "Shangxuan", "" ], [ "Chen", "Ying-Cong", "" ], [ "Li", "Xiang", "" ], [ "Wu", "An-Cong", "" ], [ "You", "Jin-Jie", "" ], [ "Zheng", "Wei-Shi", "" ] ]
TITLE: An Enhanced Deep Feature Representation for Person Re-identification ABSTRACT: Feature representation and metric learning are two critical components in person re-identification models. In this paper, we focus on the feature representation and claim that hand-crafted histogram features can be complementary to Convolutional Neural Network (CNN) features. We propose a novel feature extraction model called Feature Fusion Net (FFN) for pedestrian image representation. In FFN, back propagation makes CNN features constrained by the handcrafted features. Utilizing color histogram features (RGB, HSV, YCbCr, Lab and YIQ) and texture features (multi-scale and multi-orientation Gabor features), we get a new deep feature representation that is more discriminative and compact. Experiments on three challenging datasets (VIPeR, CUHK01, PRID450s) validates the effectiveness of our proposal.
no_new_dataset
0.947186
1606.01593
Steve Versteeg
Jean-Guy Schneider, Peter Mandile, Steve Versteeg
Generalized Suffix Tree based Multiple Sequence Alignment for Service Virtualization
In Proceedings of 24th Australasian Software Engineering Conference (ASWEC2015), pp 48-57
In Proceedings of 24th Australasian Software Engineering Conference (ASWEC2015), pp 48-57. IEEE
10.1109/ASWEC.2015.13
null
cs.SE
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Assuring quality of contemporary software systems is a very challenging task due to the often large complexity of the deployment environments in which they will operate. Service virtualization is an approach to this challenge where services within the deployment environment are emulated by synthesising service response messages from models or by recording and then replaying service interaction messages with the system. Record-and-replay techniques require an approach where (i) message prototypes can be derived from recorded system interactions (i.e. request-response sequences), (ii) a scheme to match incoming request messages against message prototypes, and (iii) the synthesis of response messages based on similarities between incoming messages and the recorded system interactions. Previous approaches in service virtualization have required a multiple sequence alignment (MSA) algorithm as a means of finding common patterns of similarities and differences between messages required by all three steps. In this paper, we present a novel MSA algorithm based on Generalized Suffix Trees (GSTs). We evaluated the accuracy and efficiency of the proposed algorithm against six enterprise service message trace datasets, with the proposed algorithm performing up to 50 times faster than standard MSA approaches. Furthermore, the algorithm has applicability to other domains beyond service virtualization.
[ { "version": "v1", "created": "Mon, 6 Jun 2016 01:45:59 GMT" } ]
2016-11-18T00:00:00
[ [ "Schneider", "Jean-Guy", "" ], [ "Mandile", "Peter", "" ], [ "Versteeg", "Steve", "" ] ]
TITLE: Generalized Suffix Tree based Multiple Sequence Alignment for Service Virtualization ABSTRACT: Assuring quality of contemporary software systems is a very challenging task due to the often large complexity of the deployment environments in which they will operate. Service virtualization is an approach to this challenge where services within the deployment environment are emulated by synthesising service response messages from models or by recording and then replaying service interaction messages with the system. Record-and-replay techniques require an approach where (i) message prototypes can be derived from recorded system interactions (i.e. request-response sequences), (ii) a scheme to match incoming request messages against message prototypes, and (iii) the synthesis of response messages based on similarities between incoming messages and the recorded system interactions. Previous approaches in service virtualization have required a multiple sequence alignment (MSA) algorithm as a means of finding common patterns of similarities and differences between messages required by all three steps. In this paper, we present a novel MSA algorithm based on Generalized Suffix Trees (GSTs). We evaluated the accuracy and efficiency of the proposed algorithm against six enterprise service message trace datasets, with the proposed algorithm performing up to 50 times faster than standard MSA approaches. Furthermore, the algorithm has applicability to other domains beyond service virtualization.
no_new_dataset
0.941654
1606.06259
Amir Zadeh
Amir Zadeh, Rowan Zellers, Eli Pincus, Louis-Philippe Morency
MOSI: Multimodal Corpus of Sentiment Intensity and Subjectivity Analysis in Online Opinion Videos
Accepted as Journal Publication in IEEE Intelligent Systems
IEEE Intelligent Systems 31.6 (2016): 82-88
null
null
cs.CL cs.MM
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
People are sharing their opinions, stories and reviews through online video sharing websites every day. Studying sentiment and subjectivity in these opinion videos is experiencing a growing attention from academia and industry. While sentiment analysis has been successful for text, it is an understudied research question for videos and multimedia content. The biggest setbacks for studies in this direction are lack of a proper dataset, methodology, baselines and statistical analysis of how information from different modality sources relate to each other. This paper introduces to the scientific community the first opinion-level annotated corpus of sentiment and subjectivity analysis in online videos called Multimodal Opinion-level Sentiment Intensity dataset (MOSI). The dataset is rigorously annotated with labels for subjectivity, sentiment intensity, per-frame and per-opinion annotated visual features, and per-milliseconds annotated audio features. Furthermore, we present baselines for future studies in this direction as well as a new multimodal fusion approach that jointly models spoken words and visual gestures.
[ { "version": "v1", "created": "Mon, 20 Jun 2016 19:23:53 GMT" }, { "version": "v2", "created": "Fri, 12 Aug 2016 02:39:40 GMT" } ]
2016-11-18T00:00:00
[ [ "Zadeh", "Amir", "" ], [ "Zellers", "Rowan", "" ], [ "Pincus", "Eli", "" ], [ "Morency", "Louis-Philippe", "" ] ]
TITLE: MOSI: Multimodal Corpus of Sentiment Intensity and Subjectivity Analysis in Online Opinion Videos ABSTRACT: People are sharing their opinions, stories and reviews through online video sharing websites every day. Studying sentiment and subjectivity in these opinion videos is experiencing a growing attention from academia and industry. While sentiment analysis has been successful for text, it is an understudied research question for videos and multimedia content. The biggest setbacks for studies in this direction are lack of a proper dataset, methodology, baselines and statistical analysis of how information from different modality sources relate to each other. This paper introduces to the scientific community the first opinion-level annotated corpus of sentiment and subjectivity analysis in online videos called Multimodal Opinion-level Sentiment Intensity dataset (MOSI). The dataset is rigorously annotated with labels for subjectivity, sentiment intensity, per-frame and per-opinion annotated visual features, and per-milliseconds annotated audio features. Furthermore, we present baselines for future studies in this direction as well as a new multimodal fusion approach that jointly models spoken words and visual gestures.
new_dataset
0.956513
1606.08150
Da Li
Hancheng Wu, Da Li, Michela Becchi
Compiler-Assisted Workload Consolidation For Efficient Dynamic Parallelism on GPU
10 pages, 10 figures, to be published in IEEE International Parallel and Distributed Processing Symposium (IPDPS) 2016
null
10.1109/IPDPS.2016.98
null
cs.DC
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
GPUs have been widely used to accelerate computations exhibiting simple patterns of parallelism - such as flat or two-level parallelism - and a degree of parallelism that can be statically determined based on the size of the input dataset. However, the effective use of GPUs for algorithms exhibiting complex patterns of parallelism, possibly known only at runtime, is still an open problem. Recently, Nvidia has introduced Dynamic Parallelism (DP) in its GPUs. By making it possible to launch kernels directly from GPU threads, this feature enables nested parallelism at runtime. However, the effective use of DP must still be understood: a naive use of this feature may suffer from significant runtime overhead and lead to GPU underutilization, resulting in poor performance. In this work, we target this problem. First, we demonstrate how a naive use of DP can result in poor performance. Second, we propose three workload consolidation schemes to improve performance and hardware utilization of DP-based codes, and we implement these code transformations in a directive-based compiler. Finally, we evaluate our framework on two categories of applications: algorithms including irregular loops and algorithms exhibiting parallel recursion. Our experiments show that our approach significantly reduces runtime overhead and improves GPU utilization, leading to speedup factors from 90x to 3300x over basic DP-based solutions and speedups from 2x to 6x over flat implementations.
[ { "version": "v1", "created": "Mon, 27 Jun 2016 07:55:23 GMT" } ]
2016-11-18T00:00:00
[ [ "Wu", "Hancheng", "" ], [ "Li", "Da", "" ], [ "Becchi", "Michela", "" ] ]
TITLE: Compiler-Assisted Workload Consolidation For Efficient Dynamic Parallelism on GPU ABSTRACT: GPUs have been widely used to accelerate computations exhibiting simple patterns of parallelism - such as flat or two-level parallelism - and a degree of parallelism that can be statically determined based on the size of the input dataset. However, the effective use of GPUs for algorithms exhibiting complex patterns of parallelism, possibly known only at runtime, is still an open problem. Recently, Nvidia has introduced Dynamic Parallelism (DP) in its GPUs. By making it possible to launch kernels directly from GPU threads, this feature enables nested parallelism at runtime. However, the effective use of DP must still be understood: a naive use of this feature may suffer from significant runtime overhead and lead to GPU underutilization, resulting in poor performance. In this work, we target this problem. First, we demonstrate how a naive use of DP can result in poor performance. Second, we propose three workload consolidation schemes to improve performance and hardware utilization of DP-based codes, and we implement these code transformations in a directive-based compiler. Finally, we evaluate our framework on two categories of applications: algorithms including irregular loops and algorithms exhibiting parallel recursion. Our experiments show that our approach significantly reduces runtime overhead and improves GPU utilization, leading to speedup factors from 90x to 3300x over basic DP-based solutions and speedups from 2x to 6x over flat implementations.
no_new_dataset
0.941708
1608.07605
Cem Aksoylar
Cem Aksoylar, Jing Qian, Venkatesh Saligrama
Clustering and Community Detection with Imbalanced Clusters
Extended version of arXiv:1309.2303 with new applications. Accepted to IEEE TSIPN
null
10.1109/TSIPN.2016.2601022
null
stat.ML cs.LG cs.SI
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Spectral clustering methods which are frequently used in clustering and community detection applications are sensitive to the specific graph constructions particularly when imbalanced clusters are present. We show that ratio cut (RCut) or normalized cut (NCut) objectives are not tailored to imbalanced cluster sizes since they tend to emphasize cut sizes over cut values. We propose a graph partitioning problem that seeks minimum cut partitions under minimum size constraints on partitions to deal with imbalanced cluster sizes. Our approach parameterizes a family of graphs by adaptively modulating node degrees on a fixed node set, yielding a set of parameter dependent cuts reflecting varying levels of imbalance. The solution to our problem is then obtained by optimizing over these parameters. We present rigorous limit cut analysis results to justify our approach and demonstrate the superiority of our method through experiments on synthetic and real datasets for data clustering, semi-supervised learning and community detection.
[ { "version": "v1", "created": "Fri, 26 Aug 2016 20:49:06 GMT" } ]
2016-11-18T00:00:00
[ [ "Aksoylar", "Cem", "" ], [ "Qian", "Jing", "" ], [ "Saligrama", "Venkatesh", "" ] ]
TITLE: Clustering and Community Detection with Imbalanced Clusters ABSTRACT: Spectral clustering methods which are frequently used in clustering and community detection applications are sensitive to the specific graph constructions particularly when imbalanced clusters are present. We show that ratio cut (RCut) or normalized cut (NCut) objectives are not tailored to imbalanced cluster sizes since they tend to emphasize cut sizes over cut values. We propose a graph partitioning problem that seeks minimum cut partitions under minimum size constraints on partitions to deal with imbalanced cluster sizes. Our approach parameterizes a family of graphs by adaptively modulating node degrees on a fixed node set, yielding a set of parameter dependent cuts reflecting varying levels of imbalance. The solution to our problem is then obtained by optimizing over these parameters. We present rigorous limit cut analysis results to justify our approach and demonstrate the superiority of our method through experiments on synthetic and real datasets for data clustering, semi-supervised learning and community detection.
no_new_dataset
0.949482
1610.04211
Julien Perez
Julien Perez and Fei Liu
Gated End-to-End Memory Networks
9 pages, 3 figures, 3 tables
null
null
null
cs.CL stat.ML
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Machine reading using differentiable reasoning models has recently shown remarkable progress. In this context, End-to-End trainable Memory Networks, MemN2N, have demonstrated promising performance on simple natural language based reasoning tasks such as factual reasoning and basic deduction. However, other tasks, namely multi-fact question-answering, positional reasoning or dialog related tasks, remain challenging particularly due to the necessity of more complex interactions between the memory and controller modules composing this family of models. In this paper, we introduce a novel end-to-end memory access regulation mechanism inspired by the current progress on the connection short-cutting principle in the field of computer vision. Concretely, we develop a Gated End-to-End trainable Memory Network architecture, GMemN2N. From the machine learning perspective, this new capability is learned in an end-to-end fashion without the use of any additional supervision signal which is, as far as our knowledge goes, the first of its kind. Our experiments show significant improvements on the most challenging tasks in the 20 bAbI dataset, without the use of any domain knowledge. Then, we show improvements on the dialog bAbI tasks including the real human-bot conversion-based Dialog State Tracking Challenge (DSTC-2) dataset. On these two datasets, our model sets the new state of the art.
[ { "version": "v1", "created": "Thu, 13 Oct 2016 19:38:03 GMT" }, { "version": "v2", "created": "Thu, 17 Nov 2016 15:09:29 GMT" } ]
2016-11-18T00:00:00
[ [ "Perez", "Julien", "" ], [ "Liu", "Fei", "" ] ]
TITLE: Gated End-to-End Memory Networks ABSTRACT: Machine reading using differentiable reasoning models has recently shown remarkable progress. In this context, End-to-End trainable Memory Networks, MemN2N, have demonstrated promising performance on simple natural language based reasoning tasks such as factual reasoning and basic deduction. However, other tasks, namely multi-fact question-answering, positional reasoning or dialog related tasks, remain challenging particularly due to the necessity of more complex interactions between the memory and controller modules composing this family of models. In this paper, we introduce a novel end-to-end memory access regulation mechanism inspired by the current progress on the connection short-cutting principle in the field of computer vision. Concretely, we develop a Gated End-to-End trainable Memory Network architecture, GMemN2N. From the machine learning perspective, this new capability is learned in an end-to-end fashion without the use of any additional supervision signal which is, as far as our knowledge goes, the first of its kind. Our experiments show significant improvements on the most challenging tasks in the 20 bAbI dataset, without the use of any domain knowledge. Then, we show improvements on the dialog bAbI tasks including the real human-bot conversion-based Dialog State Tracking Challenge (DSTC-2) dataset. On these two datasets, our model sets the new state of the art.
no_new_dataset
0.93744
1611.05340
Abhay Gupta
Abhay Gupta
Approximating Wisdom of Crowds using K-RBMs
8 pages, 1 figure
null
null
null
cs.LG
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
An important way to make large training sets is to gather noisy labels from crowds of non experts. We propose a method to aggregate noisy labels collected from a crowd of workers or annotators. Eliciting labels is important in tasks such as judging web search quality and rating products. Our method assumes that labels are generated by a probability distribution over items and labels. We formulate the method by drawing parallels between Gaussian Mixture Models (GMMs) and Restricted Boltzmann Machines (RBMs) and show that the problem of vote aggregation can be viewed as one of clustering. We use K-RBMs to perform clustering. We finally show some empirical evaluations over real datasets.
[ { "version": "v1", "created": "Wed, 16 Nov 2016 16:01:48 GMT" }, { "version": "v2", "created": "Thu, 17 Nov 2016 02:48:04 GMT" } ]
2016-11-18T00:00:00
[ [ "Gupta", "Abhay", "" ] ]
TITLE: Approximating Wisdom of Crowds using K-RBMs ABSTRACT: An important way to make large training sets is to gather noisy labels from crowds of non experts. We propose a method to aggregate noisy labels collected from a crowd of workers or annotators. Eliciting labels is important in tasks such as judging web search quality and rating products. Our method assumes that labels are generated by a probability distribution over items and labels. We formulate the method by drawing parallels between Gaussian Mixture Models (GMMs) and Restricted Boltzmann Machines (RBMs) and show that the problem of vote aggregation can be viewed as one of clustering. We use K-RBMs to perform clustering. We finally show some empirical evaluations over real datasets.
no_new_dataset
0.94699
1611.05503
Yu Liu
Yu Liu, Yanming Guo, and Michael S. Lew
On the Exploration of Convolutional Fusion Networks for Visual Recognition
23rd International Conference on MultiMedia Modeling (MMM 2017)
null
null
null
cs.CV
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Despite recent advances in multi-scale deep representations, their limitations are attributed to expensive parameters and weak fusion modules. Hence, we propose an efficient approach to fuse multi-scale deep representations, called convolutional fusion networks (CFN). Owing to using 1$\times$1 convolution and global average pooling, CFN can efficiently generate the side branches while adding few parameters. In addition, we present a locally-connected fusion module, which can learn adaptive weights for the side branches and form a discriminatively fused feature. CFN models trained on the CIFAR and ImageNet datasets demonstrate remarkable improvements over the plain CNNs. Furthermore, we generalize CFN to three new tasks, including scene recognition, fine-grained recognition and image retrieval. Our experiments show that it can obtain consistent improvements towards the transferring tasks.
[ { "version": "v1", "created": "Wed, 16 Nov 2016 23:33:38 GMT" } ]
2016-11-18T00:00:00
[ [ "Liu", "Yu", "" ], [ "Guo", "Yanming", "" ], [ "Lew", "Michael S.", "" ] ]
TITLE: On the Exploration of Convolutional Fusion Networks for Visual Recognition ABSTRACT: Despite recent advances in multi-scale deep representations, their limitations are attributed to expensive parameters and weak fusion modules. Hence, we propose an efficient approach to fuse multi-scale deep representations, called convolutional fusion networks (CFN). Owing to using 1$\times$1 convolution and global average pooling, CFN can efficiently generate the side branches while adding few parameters. In addition, we present a locally-connected fusion module, which can learn adaptive weights for the side branches and form a discriminatively fused feature. CFN models trained on the CIFAR and ImageNet datasets demonstrate remarkable improvements over the plain CNNs. Furthermore, we generalize CFN to three new tasks, including scene recognition, fine-grained recognition and image retrieval. Our experiments show that it can obtain consistent improvements towards the transferring tasks.
no_new_dataset
0.947186
1611.05521
Yang Wang
Lin Wu, Yang Wang
Robust Hashing for Multi-View Data: Jointly Learning Low-Rank Kernelized Similarity Consensus and Hash Functions
Accepted to appear in Image and Vision Computing
null
null
null
cs.LG
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Learning hash functions/codes for similarity search over multi-view data is attracting increasing attention, where similar hash codes are assigned to the data objects characterizing consistently neighborhood relationship across views. Traditional methods in this category inherently suffer three limitations: 1) they commonly adopt a two-stage scheme where similarity matrix is first constructed, followed by a subsequent hash function learning; 2) these methods are commonly developed on the assumption that data samples with multiple representations are noise-free,which is not practical in real-life applications; 3) they often incur cumbersome training model caused by the neighborhood graph construction using all $N$ points in the database ($O(N)$). In this paper, we motivate the problem of jointly and efficiently training the robust hash functions over data objects with multi-feature representations which may be noise corrupted. To achieve both the robustness and training efficiency, we propose an approach to effectively and efficiently learning low-rank kernelized \footnote{We use kernelized similarity rather than kernel, as it is not a squared symmetric matrix for data-landmark affinity matrix.} hash functions shared across views. Specifically, we utilize landmark graphs to construct tractable similarity matrices in multi-views to automatically discover neighborhood structure in the data. To learn robust hash functions, a latent low-rank kernel function is used to construct hash functions in order to accommodate linearly inseparable data. In particular, a latent kernelized similarity matrix is recovered by rank minimization on multiple kernel-based similarity matrices. Extensive experiments on real-world multi-view datasets validate the efficacy of our method in the presence of error corruptions.
[ { "version": "v1", "created": "Thu, 17 Nov 2016 01:21:26 GMT" } ]
2016-11-18T00:00:00
[ [ "Wu", "Lin", "" ], [ "Wang", "Yang", "" ] ]
TITLE: Robust Hashing for Multi-View Data: Jointly Learning Low-Rank Kernelized Similarity Consensus and Hash Functions ABSTRACT: Learning hash functions/codes for similarity search over multi-view data is attracting increasing attention, where similar hash codes are assigned to the data objects characterizing consistently neighborhood relationship across views. Traditional methods in this category inherently suffer three limitations: 1) they commonly adopt a two-stage scheme where similarity matrix is first constructed, followed by a subsequent hash function learning; 2) these methods are commonly developed on the assumption that data samples with multiple representations are noise-free,which is not practical in real-life applications; 3) they often incur cumbersome training model caused by the neighborhood graph construction using all $N$ points in the database ($O(N)$). In this paper, we motivate the problem of jointly and efficiently training the robust hash functions over data objects with multi-feature representations which may be noise corrupted. To achieve both the robustness and training efficiency, we propose an approach to effectively and efficiently learning low-rank kernelized \footnote{We use kernelized similarity rather than kernel, as it is not a squared symmetric matrix for data-landmark affinity matrix.} hash functions shared across views. Specifically, we utilize landmark graphs to construct tractable similarity matrices in multi-views to automatically discover neighborhood structure in the data. To learn robust hash functions, a latent low-rank kernel function is used to construct hash functions in order to accommodate linearly inseparable data. In particular, a latent kernelized similarity matrix is recovered by rank minimization on multiple kernel-based similarity matrices. Extensive experiments on real-world multi-view datasets validate the efficacy of our method in the presence of error corruptions.
no_new_dataset
0.952926
1611.05592
Junbo Wang
Junbo Wang, Wei Wang, Yan Huang, Liang Wang, Tieniu Tan
Multimodal Memory Modelling for Video Captioning
null
null
null
null
cs.CV
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Video captioning which automatically translates video clips into natural language sentences is a very important task in computer vision. By virtue of recent deep learning technologies, e.g., convolutional neural networks (CNNs) and recurrent neural networks (RNNs), video captioning has made great progress. However, learning an effective mapping from visual sequence space to language space is still a challenging problem. In this paper, we propose a Multimodal Memory Model (M3) to describe videos, which builds a visual and textual shared memory to model the long-term visual-textual dependency and further guide global visual attention on described targets. Specifically, the proposed M3 attaches an external memory to store and retrieve both visual and textual contents by interacting with video and sentence with multiple read and write operations. First, text representation in the Long Short-Term Memory (LSTM) based text decoder is written into the memory, and the memory contents will be read out to guide an attention to select related visual targets. Then, the selected visual information is written into the memory, which will be further read out to the text decoder. To evaluate the proposed model, we perform experiments on two publicly benchmark datasets: MSVD and MSR-VTT. The experimental results demonstrate that our method outperforms the state-of-theart methods in terms of BLEU and METEOR.
[ { "version": "v1", "created": "Thu, 17 Nov 2016 07:24:03 GMT" } ]
2016-11-18T00:00:00
[ [ "Wang", "Junbo", "" ], [ "Wang", "Wei", "" ], [ "Huang", "Yan", "" ], [ "Wang", "Liang", "" ], [ "Tan", "Tieniu", "" ] ]
TITLE: Multimodal Memory Modelling for Video Captioning ABSTRACT: Video captioning which automatically translates video clips into natural language sentences is a very important task in computer vision. By virtue of recent deep learning technologies, e.g., convolutional neural networks (CNNs) and recurrent neural networks (RNNs), video captioning has made great progress. However, learning an effective mapping from visual sequence space to language space is still a challenging problem. In this paper, we propose a Multimodal Memory Model (M3) to describe videos, which builds a visual and textual shared memory to model the long-term visual-textual dependency and further guide global visual attention on described targets. Specifically, the proposed M3 attaches an external memory to store and retrieve both visual and textual contents by interacting with video and sentence with multiple read and write operations. First, text representation in the Long Short-Term Memory (LSTM) based text decoder is written into the memory, and the memory contents will be read out to guide an attention to select related visual targets. Then, the selected visual information is written into the memory, which will be further read out to the text decoder. To evaluate the proposed model, we perform experiments on two publicly benchmark datasets: MSVD and MSR-VTT. The experimental results demonstrate that our method outperforms the state-of-theart methods in terms of BLEU and METEOR.
no_new_dataset
0.949435
1611.05603
Kai Yu
Kai Yu, Biao Leng, Zhang Zhang, Dangwei Li, Kaiqi Huang
Weakly-supervised Learning of Mid-level Features for Pedestrian Attribute Recognition and Localization
Containing 9 pages and 5 figures. Codes open-sourced on https://github.com/kyu-sz/WPAL-network
null
null
null
cs.CV
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
State-of-the-art methods treat pedestrian attribute recognition as a multi-label image classification problem. The location information of person attributes is usually eliminated or simply encoded in the rigid splitting of whole body in previous work. In this paper, we formulate the task in a weakly-supervised attribute localization framework. Based on GoogLeNet, firstly, a set of mid-level attribute features are discovered by novelly designed detection layers, where a max-pooling based weakly-supervised object detection technique is used to train these layers with only image-level labels without the need of bounding box annotations of pedestrian attributes. Secondly, attribute labels are predicted by regression of the detection response magnitudes. Finally, the locations and rough shapes of pedestrian attributes can be inferred by performing clustering on a fusion of activation maps of the detection layers, where the fusion weights are estimated as the correlation strengths between each attribute and its relevant mid-level features. Extensive experiments are performed on the two currently largest pedestrian attribute datasets, i.e. the PETA dataset and the RAP dataset. Results show that the proposed method has achieved competitive performance on attribute recognition, compared to other state-of-the-art methods. Moreover, the results of attribute localization are visualized to understand the characteristics of the proposed method.
[ { "version": "v1", "created": "Thu, 17 Nov 2016 08:20:23 GMT" } ]
2016-11-18T00:00:00
[ [ "Yu", "Kai", "" ], [ "Leng", "Biao", "" ], [ "Zhang", "Zhang", "" ], [ "Li", "Dangwei", "" ], [ "Huang", "Kaiqi", "" ] ]
TITLE: Weakly-supervised Learning of Mid-level Features for Pedestrian Attribute Recognition and Localization ABSTRACT: State-of-the-art methods treat pedestrian attribute recognition as a multi-label image classification problem. The location information of person attributes is usually eliminated or simply encoded in the rigid splitting of whole body in previous work. In this paper, we formulate the task in a weakly-supervised attribute localization framework. Based on GoogLeNet, firstly, a set of mid-level attribute features are discovered by novelly designed detection layers, where a max-pooling based weakly-supervised object detection technique is used to train these layers with only image-level labels without the need of bounding box annotations of pedestrian attributes. Secondly, attribute labels are predicted by regression of the detection response magnitudes. Finally, the locations and rough shapes of pedestrian attributes can be inferred by performing clustering on a fusion of activation maps of the detection layers, where the fusion weights are estimated as the correlation strengths between each attribute and its relevant mid-level features. Extensive experiments are performed on the two currently largest pedestrian attribute datasets, i.e. the PETA dataset and the RAP dataset. Results show that the proposed method has achieved competitive performance on attribute recognition, compared to other state-of-the-art methods. Moreover, the results of attribute localization are visualized to understand the characteristics of the proposed method.
no_new_dataset
0.947137
1611.05735
Yaniv Altshuler
Yaniv Altshuler, Alex Pentland, Shlomo Bekhor, Yoram Shiftan, Alfred Bruckstein
Optimal Dynamic Coverage Infrastructure for Large-Scale Fleets of Reconnaissance UAVs
35 pages, 19 figures
null
null
null
cs.AI
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Current state of the art in the field of UAV activation relies solely on human operators for the design and adaptation of the drones' flying routes. Furthermore, this is being done today on an individual level (one vehicle per operators), with some exceptions of a handful of new systems, that are comprised of a small number of self-organizing swarms, manually guided by a human operator. Drones-based monitoring is of great importance in variety of civilian domains, such as road safety, homeland security, and even environmental control. In its military aspect, efficiently detecting evading targets by a fleet of unmanned drones has an ever increasing impact on the ability of modern armies to engage in warfare. The latter is true both traditional symmetric conflicts among armies as well as asymmetric ones. Be it a speeding driver, a polluting trailer or a covert convoy, the basic challenge remains the same -- how can its detection probability be maximized using as little number of drones as possible. In this work we propose a novel approach for the optimization of large scale swarms of reconnaissance drones -- capable of producing on-demand optimal coverage strategies for any given search scenario. Given an estimation cost of the threat's potential damages, as well as types of monitoring drones available and their comparative performance, our proposed method generates an analytically provable strategy, stating the optimal number and types of drones to be deployed, in order to cost-efficiently monitor a pre-defined region for targets maneuvering using a given roads networks. We demonstrate our model using a unique dataset of the Israeli transportation network, on which different deployment schemes for drones deployment are evaluated.
[ { "version": "v1", "created": "Thu, 17 Nov 2016 15:28:14 GMT" } ]
2016-11-18T00:00:00
[ [ "Altshuler", "Yaniv", "" ], [ "Pentland", "Alex", "" ], [ "Bekhor", "Shlomo", "" ], [ "Shiftan", "Yoram", "" ], [ "Bruckstein", "Alfred", "" ] ]
TITLE: Optimal Dynamic Coverage Infrastructure for Large-Scale Fleets of Reconnaissance UAVs ABSTRACT: Current state of the art in the field of UAV activation relies solely on human operators for the design and adaptation of the drones' flying routes. Furthermore, this is being done today on an individual level (one vehicle per operators), with some exceptions of a handful of new systems, that are comprised of a small number of self-organizing swarms, manually guided by a human operator. Drones-based monitoring is of great importance in variety of civilian domains, such as road safety, homeland security, and even environmental control. In its military aspect, efficiently detecting evading targets by a fleet of unmanned drones has an ever increasing impact on the ability of modern armies to engage in warfare. The latter is true both traditional symmetric conflicts among armies as well as asymmetric ones. Be it a speeding driver, a polluting trailer or a covert convoy, the basic challenge remains the same -- how can its detection probability be maximized using as little number of drones as possible. In this work we propose a novel approach for the optimization of large scale swarms of reconnaissance drones -- capable of producing on-demand optimal coverage strategies for any given search scenario. Given an estimation cost of the threat's potential damages, as well as types of monitoring drones available and their comparative performance, our proposed method generates an analytically provable strategy, stating the optimal number and types of drones to be deployed, in order to cost-efficiently monitor a pre-defined region for targets maneuvering using a given roads networks. We demonstrate our model using a unique dataset of the Israeli transportation network, on which different deployment schemes for drones deployment are evaluated.
new_dataset
0.851645
1611.05751
Hamid Reza Hassanzadeh
Hamid Reza Hassanzadeh, John H. Phan, May D. Wang
A Multi-Modal Graph-Based Semi-Supervised Pipeline for Predicting Cancer Survival
in 2016 IEEE International Conference on Bioinformatics and Biomedicine (BIBM)
null
null
null
cs.LG stat.ML
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Cancer survival prediction is an active area of research that can help prevent unnecessary therapies and improve patient's quality of life. Gene expression profiling is being widely used in cancer studies to discover informative biomarkers that aid predict different clinical endpoint prediction. We use multiple modalities of data derived from RNA deep-sequencing (RNA-seq) to predict survival of cancer patients. Despite the wealth of information available in expression profiles of cancer tumors, fulfilling the aforementioned objective remains a big challenge, for the most part, due to the paucity of data samples compared to the high dimension of the expression profiles. As such, analysis of transcriptomic data modalities calls for state-of-the-art big-data analytics techniques that can maximally use all the available data to discover the relevant information hidden within a significant amount of noise. In this paper, we propose a pipeline that predicts cancer patients' survival by exploiting the structure of the input (manifold learning) and by leveraging the unlabeled samples using Laplacian support vector machines, a graph-based semi supervised learning (GSSL) paradigm. We show that under certain circumstances, no single modality per se will result in the best accuracy and by fusing different models together via a stacked generalization strategy, we may boost the accuracy synergistically. We apply our approach to two cancer datasets and present promising results. We maintain that a similar pipeline can be used for predictive tasks where labeled samples are expensive to acquire.
[ { "version": "v1", "created": "Thu, 17 Nov 2016 16:01:36 GMT" } ]
2016-11-18T00:00:00
[ [ "Hassanzadeh", "Hamid Reza", "" ], [ "Phan", "John H.", "" ], [ "Wang", "May D.", "" ] ]
TITLE: A Multi-Modal Graph-Based Semi-Supervised Pipeline for Predicting Cancer Survival ABSTRACT: Cancer survival prediction is an active area of research that can help prevent unnecessary therapies and improve patient's quality of life. Gene expression profiling is being widely used in cancer studies to discover informative biomarkers that aid predict different clinical endpoint prediction. We use multiple modalities of data derived from RNA deep-sequencing (RNA-seq) to predict survival of cancer patients. Despite the wealth of information available in expression profiles of cancer tumors, fulfilling the aforementioned objective remains a big challenge, for the most part, due to the paucity of data samples compared to the high dimension of the expression profiles. As such, analysis of transcriptomic data modalities calls for state-of-the-art big-data analytics techniques that can maximally use all the available data to discover the relevant information hidden within a significant amount of noise. In this paper, we propose a pipeline that predicts cancer patients' survival by exploiting the structure of the input (manifold learning) and by leveraging the unlabeled samples using Laplacian support vector machines, a graph-based semi supervised learning (GSSL) paradigm. We show that under certain circumstances, no single modality per se will result in the best accuracy and by fusing different models together via a stacked generalization strategy, we may boost the accuracy synergistically. We apply our approach to two cancer datasets and present promising results. We maintain that a similar pipeline can be used for predictive tasks where labeled samples are expensive to acquire.
no_new_dataset
0.949106
1611.05755
Alan Godoy
Guilherme Folego, Marcus A. Angeloni, Jos\'e Augusto Stuchi, Alan Godoy, Anderson Rocha
Cross-Domain Face Verification: Matching ID Document and Self-Portrait Photographs
XII WORKSHOP DE VIS\~AO COMPUTACIONAL (Campo Grande, Brazil). In XII Workshop de Vis\~ao Computacional (pp. 311-316) (2016)
null
null
null
cs.CV
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Cross-domain biometrics has been emerging as a new necessity, which poses several additional challenges, including harsh illumination changes, noise, pose variation, among others. In this paper, we explore approaches to cross-domain face verification, comparing self-portrait photographs ("selfies") to ID documents. We approach the problem with proper image photometric adjustment and data standardization techniques, along with deep learning methods to extract the most prominent features from the data, reducing the effects of domain shift in this problem. We validate the methods using a novel dataset comprising 50 individuals. The obtained results are promising and indicate that the adopted path is worth further investigation.
[ { "version": "v1", "created": "Thu, 17 Nov 2016 16:05:11 GMT" } ]
2016-11-18T00:00:00
[ [ "Folego", "Guilherme", "" ], [ "Angeloni", "Marcus A.", "" ], [ "Stuchi", "José Augusto", "" ], [ "Godoy", "Alan", "" ], [ "Rocha", "Anderson", "" ] ]
TITLE: Cross-Domain Face Verification: Matching ID Document and Self-Portrait Photographs ABSTRACT: Cross-domain biometrics has been emerging as a new necessity, which poses several additional challenges, including harsh illumination changes, noise, pose variation, among others. In this paper, we explore approaches to cross-domain face verification, comparing self-portrait photographs ("selfies") to ID documents. We approach the problem with proper image photometric adjustment and data standardization techniques, along with deep learning methods to extract the most prominent features from the data, reducing the effects of domain shift in this problem. We validate the methods using a novel dataset comprising 50 individuals. The obtained results are promising and indicate that the adopted path is worth further investigation.
new_dataset
0.956145
1611.05777
Hamid Reza Hassanzadeh
Hamid Reza Hassanzadeh, May D. Wang
DeeperBind: Enhancing Prediction of Sequence Specificities of DNA Binding Proteins
in 2016 IEEE International Conference on Bioinformatics and Biomedicine (BIBM)
null
null
null
cs.CV
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Transcription factors (TFs) are macromolecules that bind to \textit{cis}-regulatory specific sub-regions of DNA promoters and initiate transcription. Finding the exact location of these binding sites (aka motifs) is important in a variety of domains such as drug design and development. To address this need, several \textit{in vivo} and \textit{in vitro} techniques have been developed so far that try to characterize and predict the binding specificity of a protein to different DNA loci. The major problem with these techniques is that they are not accurate enough in prediction of the binding affinity and characterization of the corresponding motifs. As a result, downstream analysis is required to uncover the locations where proteins of interest bind. Here, we propose DeeperBind, a long short term recurrent convolutional network for prediction of protein binding specificities with respect to DNA probes. DeeperBind can model the positional dynamics of probe sequences and hence reckons with the contributions made by individual sub-regions in DNA sequences, in an effective way. Moreover, it can be trained and tested on datasets containing varying-length sequences. We apply our pipeline to the datasets derived from protein binding microarrays (PBMs), an in-vitro high-throughput technology for quantification of protein-DNA binding preferences, and present promising results. To the best of our knowledge, this is the most accurate pipeline that can predict binding specificities of DNA sequences from the data produced by high-throughput technologies through utilization of the power of deep learning for feature generation and positional dynamics modeling.
[ { "version": "v1", "created": "Thu, 17 Nov 2016 16:52:41 GMT" } ]
2016-11-18T00:00:00
[ [ "Hassanzadeh", "Hamid Reza", "" ], [ "Wang", "May D.", "" ] ]
TITLE: DeeperBind: Enhancing Prediction of Sequence Specificities of DNA Binding Proteins ABSTRACT: Transcription factors (TFs) are macromolecules that bind to \textit{cis}-regulatory specific sub-regions of DNA promoters and initiate transcription. Finding the exact location of these binding sites (aka motifs) is important in a variety of domains such as drug design and development. To address this need, several \textit{in vivo} and \textit{in vitro} techniques have been developed so far that try to characterize and predict the binding specificity of a protein to different DNA loci. The major problem with these techniques is that they are not accurate enough in prediction of the binding affinity and characterization of the corresponding motifs. As a result, downstream analysis is required to uncover the locations where proteins of interest bind. Here, we propose DeeperBind, a long short term recurrent convolutional network for prediction of protein binding specificities with respect to DNA probes. DeeperBind can model the positional dynamics of probe sequences and hence reckons with the contributions made by individual sub-regions in DNA sequences, in an effective way. Moreover, it can be trained and tested on datasets containing varying-length sequences. We apply our pipeline to the datasets derived from protein binding microarrays (PBMs), an in-vitro high-throughput technology for quantification of protein-DNA binding preferences, and present promising results. To the best of our knowledge, this is the most accurate pipeline that can predict binding specificities of DNA sequences from the data produced by high-throughput technologies through utilization of the power of deep learning for feature generation and positional dynamics modeling.
no_new_dataset
0.949856
1611.05799
Nichola Abdo
Philipp Jund, Nichola Abdo, Andreas Eitel, Wolfram Burgard
The Freiburg Groceries Dataset
Link to dataset: http://www2.informatik.uni-freiburg.de/~eitel/freiburg_groceries_dataset.html Link to code: https://github.com/PhilJd/freiburg_groceries_dataset
null
null
null
cs.CV
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
With the increasing performance of machine learning techniques in the last few years, the computer vision and robotics communities have created a large number of datasets for benchmarking object recognition tasks. These datasets cover a large spectrum of natural images and object categories, making them not only useful as a testbed for comparing machine learning approaches, but also a great resource for bootstrapping different domain-specific perception and robotic systems. One such domain is domestic environments, where an autonomous robot has to recognize a large variety of everyday objects such as groceries. This is a challenging task due to the large variety of objects and products, and where there is great need for real-world training data that goes beyond product images available online. In this paper, we address this issue and present a dataset consisting of 5,000 images covering 25 different classes of groceries, with at least 97 images per class. We collected all images from real-world settings at different stores and apartments. In contrast to existing groceries datasets, our dataset includes a large variety of perspectives, lighting conditions, and degrees of clutter. Overall, our images contain thousands of different object instances. It is our hope that machine learning and robotics researchers find this dataset of use for training, testing, and bootstrapping their approaches. As a baseline classifier to facilitate comparison, we re-trained the CaffeNet architecture (an adaptation of the well-known AlexNet) on our dataset and achieved a mean accuracy of 78.9%. We release this trained model along with the code and data splits we used in our experiments.
[ { "version": "v1", "created": "Thu, 17 Nov 2016 17:35:21 GMT" } ]
2016-11-18T00:00:00
[ [ "Jund", "Philipp", "" ], [ "Abdo", "Nichola", "" ], [ "Eitel", "Andreas", "" ], [ "Burgard", "Wolfram", "" ] ]
TITLE: The Freiburg Groceries Dataset ABSTRACT: With the increasing performance of machine learning techniques in the last few years, the computer vision and robotics communities have created a large number of datasets for benchmarking object recognition tasks. These datasets cover a large spectrum of natural images and object categories, making them not only useful as a testbed for comparing machine learning approaches, but also a great resource for bootstrapping different domain-specific perception and robotic systems. One such domain is domestic environments, where an autonomous robot has to recognize a large variety of everyday objects such as groceries. This is a challenging task due to the large variety of objects and products, and where there is great need for real-world training data that goes beyond product images available online. In this paper, we address this issue and present a dataset consisting of 5,000 images covering 25 different classes of groceries, with at least 97 images per class. We collected all images from real-world settings at different stores and apartments. In contrast to existing groceries datasets, our dataset includes a large variety of perspectives, lighting conditions, and degrees of clutter. Overall, our images contain thousands of different object instances. It is our hope that machine learning and robotics researchers find this dataset of use for training, testing, and bootstrapping their approaches. As a baseline classifier to facilitate comparison, we re-trained the CaffeNet architecture (an adaptation of the well-known AlexNet) on our dataset and achieved a mean accuracy of 78.9%. We release this trained model along with the code and data splits we used in our experiments.
new_dataset
0.967287
1611.05803
Mohamed Nait Meziane
Thomas Picon, Mohamed Nait Meziane, Philippe Ravier, Guy Lamarque, Clarisse Novello, Jean-Charles Le Bunetel, Yves Raingeaud
COOLL: Controlled On/Off Loads Library, a Public Dataset of High-Sampled Electrical Signals for Appliance Identification
5 pages, 2 figures, 3 tables
null
null
null
cs.OH
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
This paper gives a brief description of the Controlled On/Off Loads Library (COOLL) dataset. This latter is a dataset of high-sampled electrical current and voltage measurements representing individual appliances consumption. The measurements were taken in June 2016 in the PRISME laboratory of the University of Orl\'eans, France. The appliances are mainly controllable appliances (i.e. we can precisely control their turn-on/off time instants). 42 appliances of 12 types were measured at a 100 kHz sampling frequency.
[ { "version": "v1", "created": "Thu, 17 Nov 2016 18:03:05 GMT" } ]
2016-11-18T00:00:00
[ [ "Picon", "Thomas", "" ], [ "Meziane", "Mohamed Nait", "" ], [ "Ravier", "Philippe", "" ], [ "Lamarque", "Guy", "" ], [ "Novello", "Clarisse", "" ], [ "Bunetel", "Jean-Charles Le", "" ], [ "Raingeaud", "Yves", "" ] ]
TITLE: COOLL: Controlled On/Off Loads Library, a Public Dataset of High-Sampled Electrical Signals for Appliance Identification ABSTRACT: This paper gives a brief description of the Controlled On/Off Loads Library (COOLL) dataset. This latter is a dataset of high-sampled electrical current and voltage measurements representing individual appliances consumption. The measurements were taken in June 2016 in the PRISME laboratory of the University of Orl\'eans, France. The appliances are mainly controllable appliances (i.e. we can precisely control their turn-on/off time instants). 42 appliances of 12 types were measured at a 100 kHz sampling frequency.
new_dataset
0.937555
1611.05842
Dilip K. Prasad
D. K. Prasad, D. Rajan, L. Rachmawati, E. Rajabaly, C. Quek
Video Processing from Electro-optical Sensors for Object Detection and Tracking in Maritime Environment: A Survey
23 pages
null
null
null
cs.CV
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We present a survey on maritime object detection and tracking approaches, which are essential for the development of a navigational system for autonomous ships. The electro-optical (EO) sensor considered here is a video camera that operates in the visible or the infrared spectra, which conventionally complement radar and sonar and have demonstrated effectiveness for situational awareness at sea has demonstrated its effectiveness over the last few years. This paper provides a comprehensive overview of various approaches of video processing for object detection and tracking in the maritime environment. We follow an approach-based taxonomy wherein the advantages and limitations of each approach are compared. The object detection system consists of the following modules: horizon detection, static background subtraction and foreground segmentation. Each of these has been studied extensively in maritime situations and has been shown to be challenging due to the presence of background motion especially due to waves and wakes. The main processes involved in object tracking include video frame registration, dynamic background subtraction, and the object tracking algorithm itself. The challenges for robust tracking arise due to camera motion, dynamic background and low contrast of tracked object, possibly due to environmental degradation. The survey also discusses multisensor approaches and commercial maritime systems that use EO sensors. The survey also highlights methods from computer vision research which hold promise to perform well in maritime EO data processing. Performance of several maritime and computer vision techniques is evaluated on newly proposed Singapore Maritime Dataset.
[ { "version": "v1", "created": "Thu, 17 Nov 2016 20:11:51 GMT" } ]
2016-11-18T00:00:00
[ [ "Prasad", "D. K.", "" ], [ "Rajan", "D.", "" ], [ "Rachmawati", "L.", "" ], [ "Rajabaly", "E.", "" ], [ "Quek", "C.", "" ] ]
TITLE: Video Processing from Electro-optical Sensors for Object Detection and Tracking in Maritime Environment: A Survey ABSTRACT: We present a survey on maritime object detection and tracking approaches, which are essential for the development of a navigational system for autonomous ships. The electro-optical (EO) sensor considered here is a video camera that operates in the visible or the infrared spectra, which conventionally complement radar and sonar and have demonstrated effectiveness for situational awareness at sea has demonstrated its effectiveness over the last few years. This paper provides a comprehensive overview of various approaches of video processing for object detection and tracking in the maritime environment. We follow an approach-based taxonomy wherein the advantages and limitations of each approach are compared. The object detection system consists of the following modules: horizon detection, static background subtraction and foreground segmentation. Each of these has been studied extensively in maritime situations and has been shown to be challenging due to the presence of background motion especially due to waves and wakes. The main processes involved in object tracking include video frame registration, dynamic background subtraction, and the object tracking algorithm itself. The challenges for robust tracking arise due to camera motion, dynamic background and low contrast of tracked object, possibly due to environmental degradation. The survey also discusses multisensor approaches and commercial maritime systems that use EO sensors. The survey also highlights methods from computer vision research which hold promise to perform well in maritime EO data processing. Performance of several maritime and computer vision techniques is evaluated on newly proposed Singapore Maritime Dataset.
no_new_dataset
0.948822
physics/0701084
Alessandra Retico
P. Delogu, M.E. Fantacci, A. Preite Martinez, A. Retico, A. Stefanini, A. Tata
A scalable system for microcalcification cluster automated detection in a distributed mammographic database
6 pages, 4 figures; Proceedings of the IEEE NNS and MIC Conference, October 23-29, 2005, Puerto Rico
Nuclear Science Symposium Conference Record, 2005 IEEE, Volume 3, 23-29 Oct. 2005, 5 pp
10.1109/NSSMIC.2005.1596609
null
physics.med-ph
null
A computer-aided detection (CADe) system for microcalcification cluster identification in mammograms has been developed in the framework of the EU-founded MammoGrid project. The CADe software is mainly based on wavelet transforms and artificial neural networks. It is able to identify microcalcifications in different datasets of mammograms (i.e. acquired with different machines and settings, digitized with different pitch and bit depth or direct digital ones). The CADe can be remotely run from GRID-connected acquisition and annotation stations, supporting clinicians from geographically distant locations in the interpretation of mammographic data. We report and discuss the system performances on different datasets of mammograms and the status of the GRID-enabled CADe analysis.
[ { "version": "v1", "created": "Mon, 8 Jan 2007 11:08:52 GMT" } ]
2016-11-18T00:00:00
[ [ "Delogu", "P.", "" ], [ "Fantacci", "M. E.", "" ], [ "Martinez", "A. Preite", "" ], [ "Retico", "A.", "" ], [ "Stefanini", "A.", "" ], [ "Tata", "A.", "" ] ]
TITLE: A scalable system for microcalcification cluster automated detection in a distributed mammographic database ABSTRACT: A computer-aided detection (CADe) system for microcalcification cluster identification in mammograms has been developed in the framework of the EU-founded MammoGrid project. The CADe software is mainly based on wavelet transforms and artificial neural networks. It is able to identify microcalcifications in different datasets of mammograms (i.e. acquired with different machines and settings, digitized with different pitch and bit depth or direct digital ones). The CADe can be remotely run from GRID-connected acquisition and annotation stations, supporting clinicians from geographically distant locations in the interpretation of mammographic data. We report and discuss the system performances on different datasets of mammograms and the status of the GRID-enabled CADe analysis.
no_new_dataset
0.953362
0808.3546
Ioan Raicu
Ioan Raicu, Yong Zhao, Ian Foster, Alex Szalay
Accelerating Large-scale Data Exploration through Data Diffusion
IEEE/ACM International Workshop on Data-Aware Distributed Computing 2008
null
10.1145/1383519.1383521
null
cs.DC
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Data-intensive applications often require exploratory analysis of large datasets. If analysis is performed on distributed resources, data locality can be crucial to high throughput and performance. We propose a "data diffusion" approach that acquires compute and storage resources dynamically, replicates data in response to demand, and schedules computations close to data. As demand increases, more resources are acquired, thus allowing faster response to subsequent requests that refer to the same data; when demand drops, resources are released. This approach can provide the benefits of dedicated hardware without the associated high costs, depending on workload and resource characteristics. The approach is reminiscent of cooperative caching, web-caching, and peer-to-peer storage systems, but addresses different application demands. Other data-aware scheduling approaches assume dedicated resources, which can be expensive and/or inefficient if load varies significantly. To explore the feasibility of the data diffusion approach, we have extended the Falkon resource provisioning and task scheduling system to support data caching and data-aware scheduling. Performance results from both micro-benchmarks and a large scale astronomy application demonstrate that our approach improves performance relative to alternative approaches, as well as provides improved scalability as aggregated I/O bandwidth scales linearly with the number of data cache nodes.
[ { "version": "v1", "created": "Tue, 26 Aug 2008 16:02:50 GMT" } ]
2016-11-17T00:00:00
[ [ "Raicu", "Ioan", "" ], [ "Zhao", "Yong", "" ], [ "Foster", "Ian", "" ], [ "Szalay", "Alex", "" ] ]
TITLE: Accelerating Large-scale Data Exploration through Data Diffusion ABSTRACT: Data-intensive applications often require exploratory analysis of large datasets. If analysis is performed on distributed resources, data locality can be crucial to high throughput and performance. We propose a "data diffusion" approach that acquires compute and storage resources dynamically, replicates data in response to demand, and schedules computations close to data. As demand increases, more resources are acquired, thus allowing faster response to subsequent requests that refer to the same data; when demand drops, resources are released. This approach can provide the benefits of dedicated hardware without the associated high costs, depending on workload and resource characteristics. The approach is reminiscent of cooperative caching, web-caching, and peer-to-peer storage systems, but addresses different application demands. Other data-aware scheduling approaches assume dedicated resources, which can be expensive and/or inefficient if load varies significantly. To explore the feasibility of the data diffusion approach, we have extended the Falkon resource provisioning and task scheduling system to support data caching and data-aware scheduling. Performance results from both micro-benchmarks and a large scale astronomy application demonstrate that our approach improves performance relative to alternative approaches, as well as provides improved scalability as aggregated I/O bandwidth scales linearly with the number of data cache nodes.
no_new_dataset
0.947478
0904.3310
Shariq Bashir Mr.
Shariq Bashir, Abdul Rauf Baig
FastLMFI: An Efficient Approach for Local Maximal Patterns Propagation and Maximal Patterns Superset Checking
8 Pages, In the proceedings of 4th ACS/IEEE International Conference on Computer Systems and Applications 2006, March 8, 2006, Dubai/Sharjah, UAE, 2006, Page(s) 452-459
null
10.1109/AICCSA.2006.205130
null
cs.DB cs.AI cs.DS
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Maximal frequent patterns superset checking plays an important role in the efficient mining of complete Maximal Frequent Itemsets (MFI) and maximal search space pruning. In this paper we present a new indexing approach, FastLMFI for local maximal frequent patterns (itemset) propagation and maximal patterns superset checking. Experimental results on different sparse and dense datasets show that our work is better than the previous well known progressive focusing technique. We have also integrated our superset checking approach with an existing state of the art maximal itemsets algorithm Mafia, and compare our results with current best maximal itemsets algorithms afopt-max and FP (zhu)-max. Our results outperform afopt-max and FP (zhu)-max on dense (chess and mushroom) datasets on almost all support thresholds, which shows the effectiveness of our approach.
[ { "version": "v1", "created": "Tue, 21 Apr 2009 18:33:04 GMT" } ]
2016-11-17T00:00:00
[ [ "Bashir", "Shariq", "" ], [ "Baig", "Abdul Rauf", "" ] ]
TITLE: FastLMFI: An Efficient Approach for Local Maximal Patterns Propagation and Maximal Patterns Superset Checking ABSTRACT: Maximal frequent patterns superset checking plays an important role in the efficient mining of complete Maximal Frequent Itemsets (MFI) and maximal search space pruning. In this paper we present a new indexing approach, FastLMFI for local maximal frequent patterns (itemset) propagation and maximal patterns superset checking. Experimental results on different sparse and dense datasets show that our work is better than the previous well known progressive focusing technique. We have also integrated our superset checking approach with an existing state of the art maximal itemsets algorithm Mafia, and compare our results with current best maximal itemsets algorithms afopt-max and FP (zhu)-max. Our results outperform afopt-max and FP (zhu)-max on dense (chess and mushroom) datasets on almost all support thresholds, which shows the effectiveness of our approach.
no_new_dataset
0.950549
0904.3312
Shariq Bashir Mr.
Shariq Bashir, and Abdul Rauf Baig
HybridMiner: Mining Maximal Frequent Itemsets Using Hybrid Database Representation Approach
8 Pages In the proceedings of 9th IEEE-INMIC 2005, Karachi, Pakistan, 2005
null
10.1109/INMIC.2005.334484
null
cs.DB cs.AI cs.DS
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
In this paper we present a novel hybrid (arraybased layout and vertical bitmap layout) database representation approach for mining complete Maximal Frequent Itemset (MFI) on sparse and large datasets. Our work is novel in terms of scalability, item search order and two horizontal and vertical projection techniques. We also present a maximal algorithm using this hybrid database representation approach. Different experimental results on real and sparse benchmark datasets show that our approach is better than previous state of art maximal algorithms.
[ { "version": "v1", "created": "Tue, 21 Apr 2009 18:38:25 GMT" } ]
2016-11-17T00:00:00
[ [ "Bashir", "Shariq", "" ], [ "Baig", "Abdul Rauf", "" ] ]
TITLE: HybridMiner: Mining Maximal Frequent Itemsets Using Hybrid Database Representation Approach ABSTRACT: In this paper we present a novel hybrid (arraybased layout and vertical bitmap layout) database representation approach for mining complete Maximal Frequent Itemset (MFI) on sparse and large datasets. Our work is novel in terms of scalability, item search order and two horizontal and vertical projection techniques. We also present a maximal algorithm using this hybrid database representation approach. Different experimental results on real and sparse benchmark datasets show that our approach is better than previous state of art maximal algorithms.
no_new_dataset
0.948775
0906.0391
Ilya Volnyansky
Ilya Volnyansky, Vladimir Pestov
Curse of Dimensionality in Pivot-based Indexes
9 pp., 4 figures, latex 2e, a revised submission to the 2nd International Workshop on Similarity Search and Applications, 2009
Proc. 2nd Int. Workshop on Similarity Search and Applications (SISAP 2009), Prague, Aug. 29-30, 2009, T. Skopal and P. Zezula (eds.), IEEE Computer Society, Los Alamitos--Washington--Tokyo, 2009, pp. 39-46.
10.1109/SISAP.2009.9
null
cs.DS
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We offer a theoretical validation of the curse of dimensionality in the pivot-based indexing of datasets for similarity search, by proving, in the framework of statistical learning, that in high dimensions no pivot-based indexing scheme can essentially outperform the linear scan. A study of the asymptotic performance of pivot-based indexing schemes is performed on a sequence of datasets modeled as samples $X_d$ picked in i.i.d. fashion from metric spaces $\Omega_d$. We allow the size of the dataset $n=n_d$ to be such that $d$, the ``dimension'', is superlogarithmic but subpolynomial in $n$. The number of pivots is allowed to grow as $o(n/d)$. We pick the least restrictive cost model of similarity search where we count each distance calculation as a single computation and disregard the rest. We demonstrate that if the intrinsic dimension of the spaces $\Omega_d$ in the sense of concentration of measure phenomenon is $O(d)$, then the performance of similarity search pivot-based indexes is asymptotically linear in $n$.
[ { "version": "v1", "created": "Tue, 2 Jun 2009 00:41:46 GMT" }, { "version": "v2", "created": "Thu, 18 Jun 2009 23:50:44 GMT" } ]
2016-11-17T00:00:00
[ [ "Volnyansky", "Ilya", "" ], [ "Pestov", "Vladimir", "" ] ]
TITLE: Curse of Dimensionality in Pivot-based Indexes ABSTRACT: We offer a theoretical validation of the curse of dimensionality in the pivot-based indexing of datasets for similarity search, by proving, in the framework of statistical learning, that in high dimensions no pivot-based indexing scheme can essentially outperform the linear scan. A study of the asymptotic performance of pivot-based indexing schemes is performed on a sequence of datasets modeled as samples $X_d$ picked in i.i.d. fashion from metric spaces $\Omega_d$. We allow the size of the dataset $n=n_d$ to be such that $d$, the ``dimension'', is superlogarithmic but subpolynomial in $n$. The number of pivots is allowed to grow as $o(n/d)$. We pick the least restrictive cost model of similarity search where we count each distance calculation as a single computation and disregard the rest. We demonstrate that if the intrinsic dimension of the spaces $\Omega_d$ in the sense of concentration of measure phenomenon is $O(d)$, then the performance of similarity search pivot-based indexes is asymptotically linear in $n$.
no_new_dataset
0.943086
0911.2904
Maxim Raginsky
Maxim Raginsky, Rebecca Willett, Corinne Horn, Jorge Silva, Roummel Marcia
Sequential anomaly detection in the presence of noise and limited feedback
19 pages, 12 pdf figures; final version to be published in IEEE Transactions on Information Theory
null
10.1109/TIT.2012.2201375
null
cs.LG
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
This paper describes a methodology for detecting anomalies from sequentially observed and potentially noisy data. The proposed approach consists of two main elements: (1) {\em filtering}, or assigning a belief or likelihood to each successive measurement based upon our ability to predict it from previous noisy observations, and (2) {\em hedging}, or flagging potential anomalies by comparing the current belief against a time-varying and data-adaptive threshold. The threshold is adjusted based on the available feedback from an end user. Our algorithms, which combine universal prediction with recent work on online convex programming, do not require computing posterior distributions given all current observations and involve simple primal-dual parameter updates. At the heart of the proposed approach lie exponential-family models which can be used in a wide variety of contexts and applications, and which yield methods that achieve sublinear per-round regret against both static and slowly varying product distributions with marginals drawn from the same exponential family. Moreover, the regret against static distributions coincides with the minimax value of the corresponding online strongly convex game. We also prove bounds on the number of mistakes made during the hedging step relative to the best offline choice of the threshold with access to all estimated beliefs and feedback signals. We validate the theory on synthetic data drawn from a time-varying distribution over binary vectors of high dimensionality, as well as on the Enron email dataset.
[ { "version": "v1", "created": "Sun, 15 Nov 2009 18:43:10 GMT" }, { "version": "v2", "created": "Wed, 14 Jul 2010 17:30:25 GMT" }, { "version": "v3", "created": "Sun, 5 Feb 2012 23:11:54 GMT" }, { "version": "v4", "created": "Tue, 13 Mar 2012 16:11:21 GMT" } ]
2016-11-17T00:00:00
[ [ "Raginsky", "Maxim", "" ], [ "Willett", "Rebecca", "" ], [ "Horn", "Corinne", "" ], [ "Silva", "Jorge", "" ], [ "Marcia", "Roummel", "" ] ]
TITLE: Sequential anomaly detection in the presence of noise and limited feedback ABSTRACT: This paper describes a methodology for detecting anomalies from sequentially observed and potentially noisy data. The proposed approach consists of two main elements: (1) {\em filtering}, or assigning a belief or likelihood to each successive measurement based upon our ability to predict it from previous noisy observations, and (2) {\em hedging}, or flagging potential anomalies by comparing the current belief against a time-varying and data-adaptive threshold. The threshold is adjusted based on the available feedback from an end user. Our algorithms, which combine universal prediction with recent work on online convex programming, do not require computing posterior distributions given all current observations and involve simple primal-dual parameter updates. At the heart of the proposed approach lie exponential-family models which can be used in a wide variety of contexts and applications, and which yield methods that achieve sublinear per-round regret against both static and slowly varying product distributions with marginals drawn from the same exponential family. Moreover, the regret against static distributions coincides with the minimax value of the corresponding online strongly convex game. We also prove bounds on the number of mistakes made during the hedging step relative to the best offline choice of the threshold with access to all estimated beliefs and feedback signals. We validate the theory on synthetic data drawn from a time-varying distribution over binary vectors of high dimensionality, as well as on the Enron email dataset.
no_new_dataset
0.944638
1001.2411
Uwe Aickelin
Julie Greensmith, Jamie Twycross, Uwe Aickelin
Dendritic Cells for Anomaly Detection
8 pages, 10 tables, 4 figures, IEEE Congress on Evolutionary Computation (CEC2006), Vancouver, Canada
Proceedings of the IEEE Congress on Evolutionary Computation (CEC2006), Vancouver, Canada
10.1109/CEC.2006.1688374
null
cs.AI cs.NE
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Artificial immune systems, more specifically the negative selection algorithm, have previously been applied to intrusion detection. The aim of this research is to develop an intrusion detection system based on a novel concept in immunology, the Danger Theory. Dendritic Cells (DCs) are antigen presenting cells and key to the activation of the human signals from the host tissue and correlate these signals with proteins know as antigens. In algorithmic terms, individual DCs perform multi-sensor data fusion based on time-windows. The whole population of DCs asynchronously correlates the fused signals with a secondary data stream. The behaviour of human DCs is abstracted to form the DC Algorithm (DCA), which is implemented using an immune inspired framework, libtissue. This system is used to detect context switching for a basic machine learning dataset and to detect outgoing portscans in real-time. Experimental results show a significant difference between an outgoing portscan and normal traffic.
[ { "version": "v1", "created": "Thu, 14 Jan 2010 10:51:41 GMT" } ]
2016-11-17T00:00:00
[ [ "Greensmith", "Julie", "" ], [ "Twycross", "Jamie", "" ], [ "Aickelin", "Uwe", "" ] ]
TITLE: Dendritic Cells for Anomaly Detection ABSTRACT: Artificial immune systems, more specifically the negative selection algorithm, have previously been applied to intrusion detection. The aim of this research is to develop an intrusion detection system based on a novel concept in immunology, the Danger Theory. Dendritic Cells (DCs) are antigen presenting cells and key to the activation of the human signals from the host tissue and correlate these signals with proteins know as antigens. In algorithmic terms, individual DCs perform multi-sensor data fusion based on time-windows. The whole population of DCs asynchronously correlates the fused signals with a secondary data stream. The behaviour of human DCs is abstracted to form the DC Algorithm (DCA), which is implemented using an immune inspired framework, libtissue. This system is used to detect context switching for a basic machine learning dataset and to detect outgoing portscans in real-time. Experimental results show a significant difference between an outgoing portscan and normal traffic.
no_new_dataset
0.943556