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1612.08333
Karthik Bangalore Mani
Karthik Bangalore Mani
Text Summarization using Deep Learning and Ridge Regression
4 pages,10 figures
null
null
null
cs.CL
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We develop models and extract relevant features for automatic text summarization and investigate the performance of different models on the DUC 2001 dataset. Two different models were developed, one being a ridge regressor and the other one was a multi-layer perceptron. The hyperparameters were varied and their performance were noted. We segregated the summarization task into 2 main steps, the first being sentence ranking and the second step being sentence selection. In the first step, given a document, we sort the sentences based on their Importance, and in the second step, in order to obtain non-redundant sentences, we weed out the sentences that are have high similarity with the previously selected sentences.
[ { "version": "v1", "created": "Mon, 26 Dec 2016 07:17:30 GMT" }, { "version": "v2", "created": "Tue, 13 Jun 2017 06:37:24 GMT" }, { "version": "v3", "created": "Wed, 14 Jun 2017 00:23:45 GMT" }, { "version": "v4", "created": "Thu, 15 Jun 2017 02:42:47 GMT" } ]
2017-06-16T00:00:00
[ [ "Mani", "Karthik Bangalore", "" ] ]
TITLE: Text Summarization using Deep Learning and Ridge Regression ABSTRACT: We develop models and extract relevant features for automatic text summarization and investigate the performance of different models on the DUC 2001 dataset. Two different models were developed, one being a ridge regressor and the other one was a multi-layer perceptron. The hyperparameters were varied and their performance were noted. We segregated the summarization task into 2 main steps, the first being sentence ranking and the second step being sentence selection. In the first step, given a document, we sort the sentences based on their Importance, and in the second step, in order to obtain non-redundant sentences, we weed out the sentences that are have high similarity with the previously selected sentences.
no_new_dataset
0.955527
1701.02593
Diego Marcheggiani
Diego Marcheggiani, Anton Frolov, Ivan Titov
A Simple and Accurate Syntax-Agnostic Neural Model for Dependency-based Semantic Role Labeling
To appear in CoNLL 2017
null
null
null
cs.CL cs.AI
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We introduce a simple and accurate neural model for dependency-based semantic role labeling. Our model predicts predicate-argument dependencies relying on states of a bidirectional LSTM encoder. The semantic role labeler achieves competitive performance on English, even without any kind of syntactic information and only using local inference. However, when automatically predicted part-of-speech tags are provided as input, it substantially outperforms all previous local models and approaches the best reported results on the English CoNLL-2009 dataset. We also consider Chinese, Czech and Spanish where our approach also achieves competitive results. Syntactic parsers are unreliable on out-of-domain data, so standard (i.e., syntactically-informed) SRL models are hindered when tested in this setting. Our syntax-agnostic model appears more robust, resulting in the best reported results on standard out-of-domain test sets.
[ { "version": "v1", "created": "Tue, 10 Jan 2017 14:01:47 GMT" }, { "version": "v2", "created": "Thu, 15 Jun 2017 16:47:47 GMT" } ]
2017-06-16T00:00:00
[ [ "Marcheggiani", "Diego", "" ], [ "Frolov", "Anton", "" ], [ "Titov", "Ivan", "" ] ]
TITLE: A Simple and Accurate Syntax-Agnostic Neural Model for Dependency-based Semantic Role Labeling ABSTRACT: We introduce a simple and accurate neural model for dependency-based semantic role labeling. Our model predicts predicate-argument dependencies relying on states of a bidirectional LSTM encoder. The semantic role labeler achieves competitive performance on English, even without any kind of syntactic information and only using local inference. However, when automatically predicted part-of-speech tags are provided as input, it substantially outperforms all previous local models and approaches the best reported results on the English CoNLL-2009 dataset. We also consider Chinese, Czech and Spanish where our approach also achieves competitive results. Syntactic parsers are unreliable on out-of-domain data, so standard (i.e., syntactically-informed) SRL models are hindered when tested in this setting. Our syntax-agnostic model appears more robust, resulting in the best reported results on standard out-of-domain test sets.
no_new_dataset
0.948822
1702.02519
Adrian Benton
Adrian Benton, Huda Khayrallah, Biman Gujral, Dee Ann Reisinger, Sheng Zhang, Raman Arora
Deep Generalized Canonical Correlation Analysis
14 pages, 6 figures
null
null
null
cs.LG cs.AI stat.ML
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We present Deep Generalized Canonical Correlation Analysis (DGCCA) -- a method for learning nonlinear transformations of arbitrarily many views of data, such that the resulting transformations are maximally informative of each other. While methods for nonlinear two-view representation learning (Deep CCA, (Andrew et al., 2013)) and linear many-view representation learning (Generalized CCA (Horst, 1961)) exist, DGCCA is the first CCA-style multiview representation learning technique that combines the flexibility of nonlinear (deep) representation learning with the statistical power of incorporating information from many independent sources, or views. We present the DGCCA formulation as well as an efficient stochastic optimization algorithm for solving it. We learn DGCCA representations on two distinct datasets for three downstream tasks: phonetic transcription from acoustic and articulatory measurements, and recommending hashtags and friends on a dataset of Twitter users. We find that DGCCA representations soundly beat existing methods at phonetic transcription and hashtag recommendation, and in general perform no worse than standard linear many-view techniques.
[ { "version": "v1", "created": "Wed, 8 Feb 2017 16:57:48 GMT" }, { "version": "v2", "created": "Thu, 15 Jun 2017 00:06:08 GMT" } ]
2017-06-16T00:00:00
[ [ "Benton", "Adrian", "" ], [ "Khayrallah", "Huda", "" ], [ "Gujral", "Biman", "" ], [ "Reisinger", "Dee Ann", "" ], [ "Zhang", "Sheng", "" ], [ "Arora", "Raman", "" ] ]
TITLE: Deep Generalized Canonical Correlation Analysis ABSTRACT: We present Deep Generalized Canonical Correlation Analysis (DGCCA) -- a method for learning nonlinear transformations of arbitrarily many views of data, such that the resulting transformations are maximally informative of each other. While methods for nonlinear two-view representation learning (Deep CCA, (Andrew et al., 2013)) and linear many-view representation learning (Generalized CCA (Horst, 1961)) exist, DGCCA is the first CCA-style multiview representation learning technique that combines the flexibility of nonlinear (deep) representation learning with the statistical power of incorporating information from many independent sources, or views. We present the DGCCA formulation as well as an efficient stochastic optimization algorithm for solving it. We learn DGCCA representations on two distinct datasets for three downstream tasks: phonetic transcription from acoustic and articulatory measurements, and recommending hashtags and friends on a dataset of Twitter users. We find that DGCCA representations soundly beat existing methods at phonetic transcription and hashtag recommendation, and in general perform no worse than standard linear many-view techniques.
no_new_dataset
0.948489
1706.03038
Mohammadamin Barekatain
Mohammadamin Barekatain, Miquel Mart\'i, Hsueh-Fu Shih, Samuel Murray, Kotaro Nakayama, Yutaka Matsuo and Helmut Prendinger
Okutama-Action: An Aerial View Video Dataset for Concurrent Human Action Detection
Computer Vision and Pattern Recognition Workshops (CVPRW), Hawaii, USA, 2017
null
null
null
cs.CV
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Despite significant progress in the development of human action detection datasets and algorithms, no current dataset is representative of real-world aerial view scenarios. We present Okutama-Action, a new video dataset for aerial view concurrent human action detection. It consists of 43 minute-long fully-annotated sequences with 12 action classes. Okutama-Action features many challenges missing in current datasets, including dynamic transition of actions, significant changes in scale and aspect ratio, abrupt camera movement, as well as multi-labeled actors. As a result, our dataset is more challenging than existing ones, and will help push the field forward to enable real-world applications.
[ { "version": "v1", "created": "Fri, 9 Jun 2017 16:54:51 GMT" }, { "version": "v2", "created": "Thu, 15 Jun 2017 16:04:01 GMT" } ]
2017-06-16T00:00:00
[ [ "Barekatain", "Mohammadamin", "" ], [ "Martí", "Miquel", "" ], [ "Shih", "Hsueh-Fu", "" ], [ "Murray", "Samuel", "" ], [ "Nakayama", "Kotaro", "" ], [ "Matsuo", "Yutaka", "" ], [ "Prendinger", "Helmut", "" ] ]
TITLE: Okutama-Action: An Aerial View Video Dataset for Concurrent Human Action Detection ABSTRACT: Despite significant progress in the development of human action detection datasets and algorithms, no current dataset is representative of real-world aerial view scenarios. We present Okutama-Action, a new video dataset for aerial view concurrent human action detection. It consists of 43 minute-long fully-annotated sequences with 12 action classes. Okutama-Action features many challenges missing in current datasets, including dynamic transition of actions, significant changes in scale and aspect ratio, abrupt camera movement, as well as multi-labeled actors. As a result, our dataset is more challenging than existing ones, and will help push the field forward to enable real-world applications.
new_dataset
0.955527
1706.03610
Georg Wiese
Georg Wiese, Dirk Weissenborn, Mariana Neves
Neural Domain Adaptation for Biomedical Question Answering
null
null
null
null
cs.CL cs.AI cs.NE
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Factoid question answering (QA) has recently benefited from the development of deep learning (DL) systems. Neural network models outperform traditional approaches in domains where large datasets exist, such as SQuAD (ca. 100,000 questions) for Wikipedia articles. However, these systems have not yet been applied to QA in more specific domains, such as biomedicine, because datasets are generally too small to train a DL system from scratch. For example, the BioASQ dataset for biomedical QA comprises less then 900 factoid (single answer) and list (multiple answers) QA instances. In this work, we adapt a neural QA system trained on a large open-domain dataset (SQuAD, source) to a biomedical dataset (BioASQ, target) by employing various transfer learning techniques. Our network architecture is based on a state-of-the-art QA system, extended with biomedical word embeddings and a novel mechanism to answer list questions. In contrast to existing biomedical QA systems, our system does not rely on domain-specific ontologies, parsers or entity taggers, which are expensive to create. Despite this fact, our systems achieve state-of-the-art results on factoid questions and competitive results on list questions.
[ { "version": "v1", "created": "Mon, 12 Jun 2017 13:08:21 GMT" }, { "version": "v2", "created": "Thu, 15 Jun 2017 15:16:18 GMT" } ]
2017-06-16T00:00:00
[ [ "Wiese", "Georg", "" ], [ "Weissenborn", "Dirk", "" ], [ "Neves", "Mariana", "" ] ]
TITLE: Neural Domain Adaptation for Biomedical Question Answering ABSTRACT: Factoid question answering (QA) has recently benefited from the development of deep learning (DL) systems. Neural network models outperform traditional approaches in domains where large datasets exist, such as SQuAD (ca. 100,000 questions) for Wikipedia articles. However, these systems have not yet been applied to QA in more specific domains, such as biomedicine, because datasets are generally too small to train a DL system from scratch. For example, the BioASQ dataset for biomedical QA comprises less then 900 factoid (single answer) and list (multiple answers) QA instances. In this work, we adapt a neural QA system trained on a large open-domain dataset (SQuAD, source) to a biomedical dataset (BioASQ, target) by employing various transfer learning techniques. Our network architecture is based on a state-of-the-art QA system, extended with biomedical word embeddings and a novel mechanism to answer list questions. In contrast to existing biomedical QA systems, our system does not rely on domain-specific ontologies, parsers or entity taggers, which are expensive to create. Despite this fact, our systems achieve state-of-the-art results on factoid questions and competitive results on list questions.
no_new_dataset
0.932453
1706.04124
Jinzhuo Wang
Baoyang Chen, Wenmin Wang, Jinzhuo Wang, Xiongtao Chen
Video Imagination from a Single Image with Transformation Generation
9 pages, 10 figures
null
null
null
cs.CV
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
In this work, we focus on a challenging task: synthesizing multiple imaginary videos given a single image. Major problems come from high dimensionality of pixel space and the ambiguity of potential motions. To overcome those problems, we propose a new framework that produce imaginary videos by transformation generation. The generated transformations are applied to the original image in a novel volumetric merge network to reconstruct frames in imaginary video. Through sampling different latent variables, our method can output different imaginary video samples. The framework is trained in an adversarial way with unsupervised learning. For evaluation, we propose a new assessment metric $RIQA$. In experiments, we test on 3 datasets varying from synthetic data to natural scene. Our framework achieves promising performance in image quality assessment. The visual inspection indicates that it can successfully generate diverse five-frame videos in acceptable perceptual quality.
[ { "version": "v1", "created": "Tue, 13 Jun 2017 15:31:10 GMT" }, { "version": "v2", "created": "Thu, 15 Jun 2017 07:51:22 GMT" } ]
2017-06-16T00:00:00
[ [ "Chen", "Baoyang", "" ], [ "Wang", "Wenmin", "" ], [ "Wang", "Jinzhuo", "" ], [ "Chen", "Xiongtao", "" ] ]
TITLE: Video Imagination from a Single Image with Transformation Generation ABSTRACT: In this work, we focus on a challenging task: synthesizing multiple imaginary videos given a single image. Major problems come from high dimensionality of pixel space and the ambiguity of potential motions. To overcome those problems, we propose a new framework that produce imaginary videos by transformation generation. The generated transformations are applied to the original image in a novel volumetric merge network to reconstruct frames in imaginary video. Through sampling different latent variables, our method can output different imaginary video samples. The framework is trained in an adversarial way with unsupervised learning. For evaluation, we propose a new assessment metric $RIQA$. In experiments, we test on 3 datasets varying from synthetic data to natural scene. Our framework achieves promising performance in image quality assessment. The visual inspection indicates that it can successfully generate diverse five-frame videos in acceptable perceptual quality.
no_new_dataset
0.947914
1706.04737
Lin Yang
Lin Yang, Yizhe Zhang, Jianxu Chen, Siyuan Zhang, Danny Z. Chen
Suggestive Annotation: A Deep Active Learning Framework for Biomedical Image Segmentation
Accepted at MICCAI 2017
null
null
null
cs.CV
http://creativecommons.org/licenses/by-nc-sa/4.0/
Image segmentation is a fundamental problem in biomedical image analysis. Recent advances in deep learning have achieved promising results on many biomedical image segmentation benchmarks. However, due to large variations in biomedical images (different modalities, image settings, objects, noise, etc), to utilize deep learning on a new application, it usually needs a new set of training data. This can incur a great deal of annotation effort and cost, because only biomedical experts can annotate effectively, and often there are too many instances in images (e.g., cells) to annotate. In this paper, we aim to address the following question: With limited effort (e.g., time) for annotation, what instances should be annotated in order to attain the best performance? We present a deep active learning framework that combines fully convolutional network (FCN) and active learning to significantly reduce annotation effort by making judicious suggestions on the most effective annotation areas. We utilize uncertainty and similarity information provided by FCN and formulate a generalized version of the maximum set cover problem to determine the most representative and uncertain areas for annotation. Extensive experiments using the 2015 MICCAI Gland Challenge dataset and a lymph node ultrasound image segmentation dataset show that, using annotation suggestions by our method, state-of-the-art segmentation performance can be achieved by using only 50% of training data.
[ { "version": "v1", "created": "Thu, 15 Jun 2017 05:01:53 GMT" } ]
2017-06-16T00:00:00
[ [ "Yang", "Lin", "" ], [ "Zhang", "Yizhe", "" ], [ "Chen", "Jianxu", "" ], [ "Zhang", "Siyuan", "" ], [ "Chen", "Danny Z.", "" ] ]
TITLE: Suggestive Annotation: A Deep Active Learning Framework for Biomedical Image Segmentation ABSTRACT: Image segmentation is a fundamental problem in biomedical image analysis. Recent advances in deep learning have achieved promising results on many biomedical image segmentation benchmarks. However, due to large variations in biomedical images (different modalities, image settings, objects, noise, etc), to utilize deep learning on a new application, it usually needs a new set of training data. This can incur a great deal of annotation effort and cost, because only biomedical experts can annotate effectively, and often there are too many instances in images (e.g., cells) to annotate. In this paper, we aim to address the following question: With limited effort (e.g., time) for annotation, what instances should be annotated in order to attain the best performance? We present a deep active learning framework that combines fully convolutional network (FCN) and active learning to significantly reduce annotation effort by making judicious suggestions on the most effective annotation areas. We utilize uncertainty and similarity information provided by FCN and formulate a generalized version of the maximum set cover problem to determine the most representative and uncertain areas for annotation. Extensive experiments using the 2015 MICCAI Gland Challenge dataset and a lymph node ultrasound image segmentation dataset show that, using annotation suggestions by our method, state-of-the-art segmentation performance can be achieved by using only 50% of training data.
no_new_dataset
0.950686
1706.04769
Simone Scardapane
Simone Scardapane, Paolo Di Lorenzo
Stochastic Training of Neural Networks via Successive Convex Approximations
Preprint submitted to IEEE Transactions on Neural Networks and Learning Systems
null
null
null
stat.ML cs.LG
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
This paper proposes a new family of algorithms for training neural networks (NNs). These are based on recent developments in the field of non-convex optimization, going under the general name of successive convex approximation (SCA) techniques. The basic idea is to iteratively replace the original (non-convex, highly dimensional) learning problem with a sequence of (strongly convex) approximations, which are both accurate and simple to optimize. Differently from similar ideas (e.g., quasi-Newton algorithms), the approximations can be constructed using only first-order information of the neural network function, in a stochastic fashion, while exploiting the overall structure of the learning problem for a faster convergence. We discuss several use cases, based on different choices for the loss function (e.g., squared loss and cross-entropy loss), and for the regularization of the NN's weights. We experiment on several medium-sized benchmark problems, and on a large-scale dataset involving simulated physical data. The results show how the algorithm outperforms state-of-the-art techniques, providing faster convergence to a better minimum. Additionally, we show how the algorithm can be easily parallelized over multiple computational units without hindering its performance. In particular, each computational unit can optimize a tailored surrogate function defined on a randomly assigned subset of the input variables, whose dimension can be selected depending entirely on the available computational power.
[ { "version": "v1", "created": "Thu, 15 Jun 2017 08:11:22 GMT" } ]
2017-06-16T00:00:00
[ [ "Scardapane", "Simone", "" ], [ "Di Lorenzo", "Paolo", "" ] ]
TITLE: Stochastic Training of Neural Networks via Successive Convex Approximations ABSTRACT: This paper proposes a new family of algorithms for training neural networks (NNs). These are based on recent developments in the field of non-convex optimization, going under the general name of successive convex approximation (SCA) techniques. The basic idea is to iteratively replace the original (non-convex, highly dimensional) learning problem with a sequence of (strongly convex) approximations, which are both accurate and simple to optimize. Differently from similar ideas (e.g., quasi-Newton algorithms), the approximations can be constructed using only first-order information of the neural network function, in a stochastic fashion, while exploiting the overall structure of the learning problem for a faster convergence. We discuss several use cases, based on different choices for the loss function (e.g., squared loss and cross-entropy loss), and for the regularization of the NN's weights. We experiment on several medium-sized benchmark problems, and on a large-scale dataset involving simulated physical data. The results show how the algorithm outperforms state-of-the-art techniques, providing faster convergence to a better minimum. Additionally, we show how the algorithm can be easily parallelized over multiple computational units without hindering its performance. In particular, each computational unit can optimize a tailored surrogate function defined on a randomly assigned subset of the input variables, whose dimension can be selected depending entirely on the available computational power.
no_new_dataset
0.947137
1706.04870
Ashraf Darwish
Ayat Taha, Ashraf Darwish, and Aboul Ella Hassanien
Arabian Horse Identification Benchmark Dataset
null
null
null
null
cs.CV
http://creativecommons.org/publicdomain/zero/1.0/
The lack of a standard muzzle print database is a challenge for conducting researches in Arabian horse identification systems. Therefore, collecting a muzzle print images database is a crucial decision. The dataset presented in this paper is an option for the studies that need a dataset for testing and comparing the algorithms under development for Arabian horse identification. Our collected dataset consists of 300 color images that were collected from 50 Arabian horse muzzle species. This dataset has been collected from 50 Arabian horses with 6 muzzle print images each. A special care has been given to the quality of the collected images. The collected images cover different quality levels and degradation factors such as image rotation and image partiality for simulating real time identification operations. This dataset can be used to test the identification of Arabian horse system including the extracted features and the selected classifier.
[ { "version": "v1", "created": "Thu, 15 Jun 2017 13:58:02 GMT" } ]
2017-06-16T00:00:00
[ [ "Taha", "Ayat", "" ], [ "Darwish", "Ashraf", "" ], [ "Hassanien", "Aboul Ella", "" ] ]
TITLE: Arabian Horse Identification Benchmark Dataset ABSTRACT: The lack of a standard muzzle print database is a challenge for conducting researches in Arabian horse identification systems. Therefore, collecting a muzzle print images database is a crucial decision. The dataset presented in this paper is an option for the studies that need a dataset for testing and comparing the algorithms under development for Arabian horse identification. Our collected dataset consists of 300 color images that were collected from 50 Arabian horse muzzle species. This dataset has been collected from 50 Arabian horses with 6 muzzle print images each. A special care has been given to the quality of the collected images. The collected images cover different quality levels and degradation factors such as image rotation and image partiality for simulating real time identification operations. This dataset can be used to test the identification of Arabian horse system including the extracted features and the selected classifier.
new_dataset
0.965414
1508.06950
Kevin Chan
Sameet Sreenivasan, Kevin S. Chan, Ananthram Swami, Gyorgy Korniss and Boleslaw Szymanski
Information Cascades in Feed-based Networks of Users with Limited Attention
8 pages, 5 figures, For IEEE Transactions on Network Science and Engineering (submitted)
IEEE Transactions on Network Science and Engineering 4, 120-128 (2017)
10.1109/TNSE.2016.2625807
null
physics.soc-ph cs.SI
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We build a model of information cascades on feed-based networks, taking into account the finite attention span of users, message generation rates and message forwarding rates. Using this model, we study through simulations, the effect of the extent of user attention on the probability that the cascade becomes viral. In analogy with a branching process, we estimate the branching factor associated with the cascade process for different attention spans and different forwarding probabilities, and demonstrate that beyond a certain attention span, critical forwarding probabilities exist that constitute a threshold after which cascades can become viral. The critical forwarding probabilities have an inverse relationship with the attention span. Next, we develop a semi-analytical approach for our model, that allows us determine the branching factor for given values of message generation rates, message forwarding rates and attention spans. The branching factors obtained using this analytical approach show good agreement with those obtained through simulations. Finally, we analyze an event specific dataset obtained from Twitter, and show that estimated branching factors correlate well with the cascade size distributions associated with distinct hashtags.
[ { "version": "v1", "created": "Thu, 27 Aug 2015 17:36:45 GMT" } ]
2017-06-15T00:00:00
[ [ "Sreenivasan", "Sameet", "" ], [ "Chan", "Kevin S.", "" ], [ "Swami", "Ananthram", "" ], [ "Korniss", "Gyorgy", "" ], [ "Szymanski", "Boleslaw", "" ] ]
TITLE: Information Cascades in Feed-based Networks of Users with Limited Attention ABSTRACT: We build a model of information cascades on feed-based networks, taking into account the finite attention span of users, message generation rates and message forwarding rates. Using this model, we study through simulations, the effect of the extent of user attention on the probability that the cascade becomes viral. In analogy with a branching process, we estimate the branching factor associated with the cascade process for different attention spans and different forwarding probabilities, and demonstrate that beyond a certain attention span, critical forwarding probabilities exist that constitute a threshold after which cascades can become viral. The critical forwarding probabilities have an inverse relationship with the attention span. Next, we develop a semi-analytical approach for our model, that allows us determine the branching factor for given values of message generation rates, message forwarding rates and attention spans. The branching factors obtained using this analytical approach show good agreement with those obtained through simulations. Finally, we analyze an event specific dataset obtained from Twitter, and show that estimated branching factors correlate well with the cascade size distributions associated with distinct hashtags.
no_new_dataset
0.95222
1512.04280
Liang Lu
Liang Lu and Steve Renals
Small-footprint Deep Neural Networks with Highway Connections for Speech Recognition
5 pages, 3 figures, fixed typo, accepted by Interspeech 2016
null
null
null
cs.CL cs.LG cs.NE
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
For speech recognition, deep neural networks (DNNs) have significantly improved the recognition accuracy in most of benchmark datasets and application domains. However, compared to the conventional Gaussian mixture models, DNN-based acoustic models usually have much larger number of model parameters, making it challenging for their applications in resource constrained platforms, e.g., mobile devices. In this paper, we study the application of the recently proposed highway network to train small-footprint DNNs, which are {\it thinner} and {\it deeper}, and have significantly smaller number of model parameters compared to conventional DNNs. We investigated this approach on the AMI meeting speech transcription corpus which has around 70 hours of audio data. The highway neural networks constantly outperformed their plain DNN counterparts, and the number of model parameters can be reduced significantly without sacrificing the recognition accuracy.
[ { "version": "v1", "created": "Mon, 14 Dec 2015 12:29:32 GMT" }, { "version": "v2", "created": "Thu, 3 Mar 2016 12:14:06 GMT" }, { "version": "v3", "created": "Mon, 20 Jun 2016 10:30:54 GMT" }, { "version": "v4", "created": "Wed, 14 Jun 2017 15:17:27 GMT" } ]
2017-06-15T00:00:00
[ [ "Lu", "Liang", "" ], [ "Renals", "Steve", "" ] ]
TITLE: Small-footprint Deep Neural Networks with Highway Connections for Speech Recognition ABSTRACT: For speech recognition, deep neural networks (DNNs) have significantly improved the recognition accuracy in most of benchmark datasets and application domains. However, compared to the conventional Gaussian mixture models, DNN-based acoustic models usually have much larger number of model parameters, making it challenging for their applications in resource constrained platforms, e.g., mobile devices. In this paper, we study the application of the recently proposed highway network to train small-footprint DNNs, which are {\it thinner} and {\it deeper}, and have significantly smaller number of model parameters compared to conventional DNNs. We investigated this approach on the AMI meeting speech transcription corpus which has around 70 hours of audio data. The highway neural networks constantly outperformed their plain DNN counterparts, and the number of model parameters can be reduced significantly without sacrificing the recognition accuracy.
no_new_dataset
0.951504
1604.07243
Mattia Desana
Mattia Desana and Christoph Schn\"orr
Learning Arbitrary Sum-Product Network Leaves with Expectation-Maximization
null
null
null
null
cs.LG
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Sum-Product Networks with complex probability distribution at the leaves have been shown to be powerful tractable-inference probabilistic models. However, while learning the internal parameters has been amply studied, learning complex leaf distribution is an open problem with only few results available in special cases. In this paper we derive an efficient method to learn a very large class of leaf distributions with Expectation-Maximization. The EM updates have the form of simple weighted maximum likelihood problems, allowing to use any distribution that can be learned with maximum likelihood, even approximately. The algorithm has cost linear in the model size and converges even if only partial optimizations are performed. We demonstrate this approach with experiments on twenty real-life datasets for density estimation, using tree graphical models as leaves. Our model outperforms state-of-the-art methods for parameter learning despite using SPNs with much fewer parameters.
[ { "version": "v1", "created": "Mon, 25 Apr 2016 13:22:55 GMT" }, { "version": "v2", "created": "Mon, 12 Dec 2016 16:42:59 GMT" }, { "version": "v3", "created": "Wed, 14 Jun 2017 14:08:22 GMT" } ]
2017-06-15T00:00:00
[ [ "Desana", "Mattia", "" ], [ "Schnörr", "Christoph", "" ] ]
TITLE: Learning Arbitrary Sum-Product Network Leaves with Expectation-Maximization ABSTRACT: Sum-Product Networks with complex probability distribution at the leaves have been shown to be powerful tractable-inference probabilistic models. However, while learning the internal parameters has been amply studied, learning complex leaf distribution is an open problem with only few results available in special cases. In this paper we derive an efficient method to learn a very large class of leaf distributions with Expectation-Maximization. The EM updates have the form of simple weighted maximum likelihood problems, allowing to use any distribution that can be learned with maximum likelihood, even approximately. The algorithm has cost linear in the model size and converges even if only partial optimizations are performed. We demonstrate this approach with experiments on twenty real-life datasets for density estimation, using tree graphical models as leaves. Our model outperforms state-of-the-art methods for parameter learning despite using SPNs with much fewer parameters.
no_new_dataset
0.944995
1609.04938
Yuntian Deng
Yuntian Deng, Anssi Kanervisto, Jeffrey Ling, Alexander M. Rush
Image-to-Markup Generation with Coarse-to-Fine Attention
Accepted by ICML 2017
null
null
null
cs.CV cs.CL cs.LG cs.NE
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We present a neural encoder-decoder model to convert images into presentational markup based on a scalable coarse-to-fine attention mechanism. Our method is evaluated in the context of image-to-LaTeX generation, and we introduce a new dataset of real-world rendered mathematical expressions paired with LaTeX markup. We show that unlike neural OCR techniques using CTC-based models, attention-based approaches can tackle this non-standard OCR task. Our approach outperforms classical mathematical OCR systems by a large margin on in-domain rendered data, and, with pretraining, also performs well on out-of-domain handwritten data. To reduce the inference complexity associated with the attention-based approaches, we introduce a new coarse-to-fine attention layer that selects a support region before applying attention.
[ { "version": "v1", "created": "Fri, 16 Sep 2016 08:14:50 GMT" }, { "version": "v2", "created": "Tue, 13 Jun 2017 22:48:53 GMT" } ]
2017-06-15T00:00:00
[ [ "Deng", "Yuntian", "" ], [ "Kanervisto", "Anssi", "" ], [ "Ling", "Jeffrey", "" ], [ "Rush", "Alexander M.", "" ] ]
TITLE: Image-to-Markup Generation with Coarse-to-Fine Attention ABSTRACT: We present a neural encoder-decoder model to convert images into presentational markup based on a scalable coarse-to-fine attention mechanism. Our method is evaluated in the context of image-to-LaTeX generation, and we introduce a new dataset of real-world rendered mathematical expressions paired with LaTeX markup. We show that unlike neural OCR techniques using CTC-based models, attention-based approaches can tackle this non-standard OCR task. Our approach outperforms classical mathematical OCR systems by a large margin on in-domain rendered data, and, with pretraining, also performs well on out-of-domain handwritten data. To reduce the inference complexity associated with the attention-based approaches, we introduce a new coarse-to-fine attention layer that selects a support region before applying attention.
new_dataset
0.958731
1610.04794
Bo Yang
Bo Yang, Xiao Fu, Nicholas D. Sidiropoulos, Mingyi Hong
Towards K-means-friendly Spaces: Simultaneous Deep Learning and Clustering
Final ICML2017 version. Main paper: 10 pages; Supplementary material: 4 pages
null
null
null
cs.LG
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Most learning approaches treat dimensionality reduction (DR) and clustering separately (i.e., sequentially), but recent research has shown that optimizing the two tasks jointly can substantially improve the performance of both. The premise behind the latter genre is that the data samples are obtained via linear transformation of latent representations that are easy to cluster; but in practice, the transformation from the latent space to the data can be more complicated. In this work, we assume that this transformation is an unknown and possibly nonlinear function. To recover the `clustering-friendly' latent representations and to better cluster the data, we propose a joint DR and K-means clustering approach in which DR is accomplished via learning a deep neural network (DNN). The motivation is to keep the advantages of jointly optimizing the two tasks, while exploiting the deep neural network's ability to approximate any nonlinear function. This way, the proposed approach can work well for a broad class of generative models. Towards this end, we carefully design the DNN structure and the associated joint optimization criterion, and propose an effective and scalable algorithm to handle the formulated optimization problem. Experiments using different real datasets are employed to showcase the effectiveness of the proposed approach.
[ { "version": "v1", "created": "Sat, 15 Oct 2016 22:51:06 GMT" }, { "version": "v2", "created": "Tue, 13 Jun 2017 22:40:26 GMT" } ]
2017-06-15T00:00:00
[ [ "Yang", "Bo", "" ], [ "Fu", "Xiao", "" ], [ "Sidiropoulos", "Nicholas D.", "" ], [ "Hong", "Mingyi", "" ] ]
TITLE: Towards K-means-friendly Spaces: Simultaneous Deep Learning and Clustering ABSTRACT: Most learning approaches treat dimensionality reduction (DR) and clustering separately (i.e., sequentially), but recent research has shown that optimizing the two tasks jointly can substantially improve the performance of both. The premise behind the latter genre is that the data samples are obtained via linear transformation of latent representations that are easy to cluster; but in practice, the transformation from the latent space to the data can be more complicated. In this work, we assume that this transformation is an unknown and possibly nonlinear function. To recover the `clustering-friendly' latent representations and to better cluster the data, we propose a joint DR and K-means clustering approach in which DR is accomplished via learning a deep neural network (DNN). The motivation is to keep the advantages of jointly optimizing the two tasks, while exploiting the deep neural network's ability to approximate any nonlinear function. This way, the proposed approach can work well for a broad class of generative models. Towards this end, we carefully design the DNN structure and the associated joint optimization criterion, and propose an effective and scalable algorithm to handle the formulated optimization problem. Experiments using different real datasets are employed to showcase the effectiveness of the proposed approach.
no_new_dataset
0.946399
1702.08720
Weihua Hu
Weihua Hu, Takeru Miyato, Seiya Tokui, Eiichi Matsumoto, Masashi Sugiyama
Learning Discrete Representations via Information Maximizing Self-Augmented Training
To appear at ICML 2017
null
null
null
stat.ML cs.LG
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Learning discrete representations of data is a central machine learning task because of the compactness of the representations and ease of interpretation. The task includes clustering and hash learning as special cases. Deep neural networks are promising to be used because they can model the non-linearity of data and scale to large datasets. However, their model complexity is huge, and therefore, we need to carefully regularize the networks in order to learn useful representations that exhibit intended invariance for applications of interest. To this end, we propose a method called Information Maximizing Self-Augmented Training (IMSAT). In IMSAT, we use data augmentation to impose the invariance on discrete representations. More specifically, we encourage the predicted representations of augmented data points to be close to those of the original data points in an end-to-end fashion. At the same time, we maximize the information-theoretic dependency between data and their predicted discrete representations. Extensive experiments on benchmark datasets show that IMSAT produces state-of-the-art results for both clustering and unsupervised hash learning.
[ { "version": "v1", "created": "Tue, 28 Feb 2017 09:57:27 GMT" }, { "version": "v2", "created": "Wed, 1 Mar 2017 10:14:51 GMT" }, { "version": "v3", "created": "Wed, 14 Jun 2017 04:18:11 GMT" } ]
2017-06-15T00:00:00
[ [ "Hu", "Weihua", "" ], [ "Miyato", "Takeru", "" ], [ "Tokui", "Seiya", "" ], [ "Matsumoto", "Eiichi", "" ], [ "Sugiyama", "Masashi", "" ] ]
TITLE: Learning Discrete Representations via Information Maximizing Self-Augmented Training ABSTRACT: Learning discrete representations of data is a central machine learning task because of the compactness of the representations and ease of interpretation. The task includes clustering and hash learning as special cases. Deep neural networks are promising to be used because they can model the non-linearity of data and scale to large datasets. However, their model complexity is huge, and therefore, we need to carefully regularize the networks in order to learn useful representations that exhibit intended invariance for applications of interest. To this end, we propose a method called Information Maximizing Self-Augmented Training (IMSAT). In IMSAT, we use data augmentation to impose the invariance on discrete representations. More specifically, we encourage the predicted representations of augmented data points to be close to those of the original data points in an end-to-end fashion. At the same time, we maximize the information-theoretic dependency between data and their predicted discrete representations. Extensive experiments on benchmark datasets show that IMSAT produces state-of-the-art results for both clustering and unsupervised hash learning.
no_new_dataset
0.944893
1703.02161
Sofia Ira Ktena
Sofia Ira Ktena, Sarah Parisot, Enzo Ferrante, Martin Rajchl, Matthew Lee, Ben Glocker, Daniel Rueckert
Distance Metric Learning using Graph Convolutional Networks: Application to Functional Brain Networks
International Conference on Medical Image Computing and Computer-Assisted Interventions (MICCAI) 2017
null
null
null
cs.CV cs.LG
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Evaluating similarity between graphs is of major importance in several computer vision and pattern recognition problems, where graph representations are often used to model objects or interactions between elements. The choice of a distance or similarity metric is, however, not trivial and can be highly dependent on the application at hand. In this work, we propose a novel metric learning method to evaluate distance between graphs that leverages the power of convolutional neural networks, while exploiting concepts from spectral graph theory to allow these operations on irregular graphs. We demonstrate the potential of our method in the field of connectomics, where neuronal pathways or functional connections between brain regions are commonly modelled as graphs. In this problem, the definition of an appropriate graph similarity function is critical to unveil patterns of disruptions associated with certain brain disorders. Experimental results on the ABIDE dataset show that our method can learn a graph similarity metric tailored for a clinical application, improving the performance of a simple k-nn classifier by 11.9% compared to a traditional distance metric.
[ { "version": "v1", "created": "Tue, 7 Mar 2017 00:49:27 GMT" }, { "version": "v2", "created": "Wed, 14 Jun 2017 11:05:52 GMT" } ]
2017-06-15T00:00:00
[ [ "Ktena", "Sofia Ira", "" ], [ "Parisot", "Sarah", "" ], [ "Ferrante", "Enzo", "" ], [ "Rajchl", "Martin", "" ], [ "Lee", "Matthew", "" ], [ "Glocker", "Ben", "" ], [ "Rueckert", "Daniel", "" ] ]
TITLE: Distance Metric Learning using Graph Convolutional Networks: Application to Functional Brain Networks ABSTRACT: Evaluating similarity between graphs is of major importance in several computer vision and pattern recognition problems, where graph representations are often used to model objects or interactions between elements. The choice of a distance or similarity metric is, however, not trivial and can be highly dependent on the application at hand. In this work, we propose a novel metric learning method to evaluate distance between graphs that leverages the power of convolutional neural networks, while exploiting concepts from spectral graph theory to allow these operations on irregular graphs. We demonstrate the potential of our method in the field of connectomics, where neuronal pathways or functional connections between brain regions are commonly modelled as graphs. In this problem, the definition of an appropriate graph similarity function is critical to unveil patterns of disruptions associated with certain brain disorders. Experimental results on the ABIDE dataset show that our method can learn a graph similarity metric tailored for a clinical application, improving the performance of a simple k-nn classifier by 11.9% compared to a traditional distance metric.
no_new_dataset
0.947817
1704.08387
Jianpeng Cheng J
Jianpeng Cheng, Siva Reddy, Vijay Saraswat, Mirella Lapata
Learning Structured Natural Language Representations for Semantic Parsing
null
null
null
null
cs.CL
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We introduce a neural semantic parser that converts natural language utterances to intermediate representations in the form of predicate-argument structures, which are induced with a transition system and subsequently mapped to target domains. The semantic parser is trained end-to-end using annotated logical forms or their denotations. We obtain competitive results on various datasets. The induced predicate-argument structures shed light on the types of representations useful for semantic parsing and how these are different from linguistically motivated ones.
[ { "version": "v1", "created": "Thu, 27 Apr 2017 00:24:20 GMT" }, { "version": "v2", "created": "Wed, 17 May 2017 09:57:29 GMT" }, { "version": "v3", "created": "Wed, 14 Jun 2017 04:18:26 GMT" } ]
2017-06-15T00:00:00
[ [ "Cheng", "Jianpeng", "" ], [ "Reddy", "Siva", "" ], [ "Saraswat", "Vijay", "" ], [ "Lapata", "Mirella", "" ] ]
TITLE: Learning Structured Natural Language Representations for Semantic Parsing ABSTRACT: We introduce a neural semantic parser that converts natural language utterances to intermediate representations in the form of predicate-argument structures, which are induced with a transition system and subsequently mapped to target domains. The semantic parser is trained end-to-end using annotated logical forms or their denotations. We obtain competitive results on various datasets. The induced predicate-argument structures shed light on the types of representations useful for semantic parsing and how these are different from linguistically motivated ones.
no_new_dataset
0.941975
1705.05732
Tatiana Alessandra Bubba
Tatiana A. Bubba, Markus Juvonen, Jonatan Lehtonen, Maximilian M\"arz, Alexander Meaney, Zenith Purisha and Samuli Siltanen
Tomographic X-ray data of carved cheese
arXiv admin note: substantial text overlap with arXiv:1609.07299, arXiv:1502.04064
null
null
null
physics.med-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
This is the documentation of the tomographic X-ray data of a carved cheese slice. Data are available at www.fips.fi/dataset.php, and can be freely used for scientific purposes with appropriate references to them, and to this document in http://arxiv.org/. The data set consists of (1) the X-ray sinogram of a single 2D slice of the cheese slice with three different resolutions and (2) the corresponding measurement matrices modeling the linear operation of the X-ray transform. Each of these sinograms was obtained from a measured 360-projection fan-beam sinogram by down-sampling and taking logarithms. The original (measured) sinogram is also provided in its original form and resolution.
[ { "version": "v1", "created": "Fri, 12 May 2017 14:02:15 GMT" }, { "version": "v2", "created": "Wed, 14 Jun 2017 14:22:00 GMT" } ]
2017-06-15T00:00:00
[ [ "Bubba", "Tatiana A.", "" ], [ "Juvonen", "Markus", "" ], [ "Lehtonen", "Jonatan", "" ], [ "März", "Maximilian", "" ], [ "Meaney", "Alexander", "" ], [ "Purisha", "Zenith", "" ], [ "Siltanen", "Samuli", "" ] ]
TITLE: Tomographic X-ray data of carved cheese ABSTRACT: This is the documentation of the tomographic X-ray data of a carved cheese slice. Data are available at www.fips.fi/dataset.php, and can be freely used for scientific purposes with appropriate references to them, and to this document in http://arxiv.org/. The data set consists of (1) the X-ray sinogram of a single 2D slice of the cheese slice with three different resolutions and (2) the corresponding measurement matrices modeling the linear operation of the X-ray transform. Each of these sinograms was obtained from a measured 360-projection fan-beam sinogram by down-sampling and taking logarithms. The original (measured) sinogram is also provided in its original form and resolution.
no_new_dataset
0.924073
1706.04215
Ashwinkumar Ganesan
Mandar Haldekar, Ashwinkumar Ganesan, Tim Oates
Identifying Spatial Relations in Images using Convolutional Neural Networks
null
null
null
null
cs.AI cs.CV cs.NE
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Traditional approaches to building a large scale knowledge graph have usually relied on extracting information (entities, their properties, and relations between them) from unstructured text (e.g. Dbpedia). Recent advances in Convolutional Neural Networks (CNN) allow us to shift our focus to learning entities and relations from images, as they build robust models that require little or no pre-processing of the images. In this paper, we present an approach to identify and extract spatial relations (e.g., The girl is standing behind the table) from images using CNNs. Our research addresses two specific challenges: providing insight into how spatial relations are learned by the network and which parts of the image are used to predict these relations. We use the pre-trained network VGGNet to extract features from an image and train a Multi-layer Perceptron (MLP) on a set of synthetic images and the sun09 dataset to extract spatial relations. The MLP predicts spatial relations without a bounding box around the objects or the space in the image depicting the relation. To understand how the spatial relations are represented in the network, a heatmap is overlayed on the image to show the regions that are deemed important by the network. Also, we analyze the MLP to show the relationship between the activation of consistent groups of nodes and the prediction of a spatial relation. We show how the loss of these groups affects the networks ability to identify relations.
[ { "version": "v1", "created": "Tue, 13 Jun 2017 18:24:11 GMT" } ]
2017-06-15T00:00:00
[ [ "Haldekar", "Mandar", "" ], [ "Ganesan", "Ashwinkumar", "" ], [ "Oates", "Tim", "" ] ]
TITLE: Identifying Spatial Relations in Images using Convolutional Neural Networks ABSTRACT: Traditional approaches to building a large scale knowledge graph have usually relied on extracting information (entities, their properties, and relations between them) from unstructured text (e.g. Dbpedia). Recent advances in Convolutional Neural Networks (CNN) allow us to shift our focus to learning entities and relations from images, as they build robust models that require little or no pre-processing of the images. In this paper, we present an approach to identify and extract spatial relations (e.g., The girl is standing behind the table) from images using CNNs. Our research addresses two specific challenges: providing insight into how spatial relations are learned by the network and which parts of the image are used to predict these relations. We use the pre-trained network VGGNet to extract features from an image and train a Multi-layer Perceptron (MLP) on a set of synthetic images and the sun09 dataset to extract spatial relations. The MLP predicts spatial relations without a bounding box around the objects or the space in the image depicting the relation. To understand how the spatial relations are represented in the network, a heatmap is overlayed on the image to show the regions that are deemed important by the network. Also, we analyze the MLP to show the relationship between the activation of consistent groups of nodes and the prediction of a spatial relation. We show how the loss of these groups affects the networks ability to identify relations.
no_new_dataset
0.948058
1706.04256
Ulugbek Kamilov
Kevin Degraux, Ulugbek S. Kamilov, Petros T. Boufounos, Dehong Liu
Online Convolutional Dictionary Learning for Multimodal Imaging
null
null
null
null
cs.CV
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Computational imaging methods that can exploit multiple modalities have the potential to enhance the capabilities of traditional sensing systems. In this paper, we propose a new method that reconstructs multimodal images from their linear measurements by exploiting redundancies across different modalities. Our method combines a convolutional group-sparse representation of images with total variation (TV) regularization for high-quality multimodal imaging. We develop an online algorithm that enables the unsupervised learning of convolutional dictionaries on large-scale datasets that are typical in such applications. We illustrate the benefit of our approach in the context of joint intensity-depth imaging.
[ { "version": "v1", "created": "Tue, 13 Jun 2017 21:08:33 GMT" } ]
2017-06-15T00:00:00
[ [ "Degraux", "Kevin", "" ], [ "Kamilov", "Ulugbek S.", "" ], [ "Boufounos", "Petros T.", "" ], [ "Liu", "Dehong", "" ] ]
TITLE: Online Convolutional Dictionary Learning for Multimodal Imaging ABSTRACT: Computational imaging methods that can exploit multiple modalities have the potential to enhance the capabilities of traditional sensing systems. In this paper, we propose a new method that reconstructs multimodal images from their linear measurements by exploiting redundancies across different modalities. Our method combines a convolutional group-sparse representation of images with total variation (TV) regularization for high-quality multimodal imaging. We develop an online algorithm that enables the unsupervised learning of convolutional dictionaries on large-scale datasets that are typical in such applications. We illustrate the benefit of our approach in the context of joint intensity-depth imaging.
no_new_dataset
0.951414
1706.04285
Chenxing Xia
Chenxing Xia and Hanling Zhang and Xiuju Gao
Saliency detection by aggregating complementary background template with optimization framework
28 pages,10 figures
null
null
null
cs.CV
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
This paper proposes an unsupervised bottom-up saliency detection approach by aggregating complementary background template with refinement. Feature vectors are extracted from each superpixel to cover regional color, contrast and texture information. By using these features, a coarse detection for salient region is realized based on background template achieved by different combinations of boundary regions instead of only treating four boundaries as background. Then, by ranking the relevance of the image nodes with foreground cues extracted from the former saliency map, we obtain an improved result. Finally, smoothing operation is utilized to refine the foreground-based saliency map to improve the contrast between salient and non-salient regions until a close to binary saliency map is reached. Experimental results show that the proposed algorithm generates more accurate saliency maps and performs favorably against the state-off-the-art saliency detection methods on four publicly available datasets.
[ { "version": "v1", "created": "Wed, 14 Jun 2017 00:06:02 GMT" } ]
2017-06-15T00:00:00
[ [ "Xia", "Chenxing", "" ], [ "Zhang", "Hanling", "" ], [ "Gao", "Xiuju", "" ] ]
TITLE: Saliency detection by aggregating complementary background template with optimization framework ABSTRACT: This paper proposes an unsupervised bottom-up saliency detection approach by aggregating complementary background template with refinement. Feature vectors are extracted from each superpixel to cover regional color, contrast and texture information. By using these features, a coarse detection for salient region is realized based on background template achieved by different combinations of boundary regions instead of only treating four boundaries as background. Then, by ranking the relevance of the image nodes with foreground cues extracted from the former saliency map, we obtain an improved result. Finally, smoothing operation is utilized to refine the foreground-based saliency map to improve the contrast between salient and non-salient regions until a close to binary saliency map is reached. Experimental results show that the proposed algorithm generates more accurate saliency maps and performs favorably against the state-off-the-art saliency detection methods on four publicly available datasets.
no_new_dataset
0.952353
1706.04318
Tetsu Matsukawa
Tetsu Matsukawa, Takahiro Okabe, Einoshin Suzuki, Yoichi Sato
Hierarchical Gaussian Descriptors with Application to Person Re-Identification
14 pages, 12 figures, 4 tables
null
null
null
cs.CV
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Describing the color and textural information of a person image is one of the most crucial aspects of person re-identification (re-id). In this paper, we present novel meta-descriptors based on a hierarchical distribution of pixel features. Although hierarchical covariance descriptors have been successfully applied to image classification, the mean information of pixel features, which is absent from the covariance, tends to be the major discriminative information for person re-id. To solve this problem, we describe a local region in an image via hierarchical Gaussian distribution in which both means and covariances are included in their parameters. More specifically, the region is modeled as a set of multiple Gaussian distributions in which each Gaussian represents the appearance of a local patch. The characteristics of the set of Gaussians are again described by another Gaussian distribution. In both steps, we embed the parameters of the Gaussian into a point of Symmetric Positive Definite (SPD) matrix manifold. By changing the way to handle mean information in this embedding, we develop two hierarchical Gaussian descriptors. Additionally, we develop feature norm normalization methods with the ability to alleviate the biased trends that exist on the descriptors. The experimental results conducted on five public datasets indicate that the proposed descriptors achieve remarkably high performance on person re-id.
[ { "version": "v1", "created": "Wed, 14 Jun 2017 05:16:16 GMT" } ]
2017-06-15T00:00:00
[ [ "Matsukawa", "Tetsu", "" ], [ "Okabe", "Takahiro", "" ], [ "Suzuki", "Einoshin", "" ], [ "Sato", "Yoichi", "" ] ]
TITLE: Hierarchical Gaussian Descriptors with Application to Person Re-Identification ABSTRACT: Describing the color and textural information of a person image is one of the most crucial aspects of person re-identification (re-id). In this paper, we present novel meta-descriptors based on a hierarchical distribution of pixel features. Although hierarchical covariance descriptors have been successfully applied to image classification, the mean information of pixel features, which is absent from the covariance, tends to be the major discriminative information for person re-id. To solve this problem, we describe a local region in an image via hierarchical Gaussian distribution in which both means and covariances are included in their parameters. More specifically, the region is modeled as a set of multiple Gaussian distributions in which each Gaussian represents the appearance of a local patch. The characteristics of the set of Gaussians are again described by another Gaussian distribution. In both steps, we embed the parameters of the Gaussian into a point of Symmetric Positive Definite (SPD) matrix manifold. By changing the way to handle mean information in this embedding, we develop two hierarchical Gaussian descriptors. Additionally, we develop feature norm normalization methods with the ability to alleviate the biased trends that exist on the descriptors. The experimental results conducted on five public datasets indicate that the proposed descriptors achieve remarkably high performance on person re-id.
no_new_dataset
0.948106
1706.04372
Zhe Wang
Zhe Wang, Yanxin Yin, Jianping Shi, Wei Fang, Hongsheng Li and Xiaogang Wang
Zoom-in-Net: Deep Mining Lesions for Diabetic Retinopathy Detection
accepted by MICCAI 2017
null
null
null
cs.CV
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We propose a convolution neural network based algorithm for simultaneously diagnosing diabetic retinopathy and highlighting suspicious regions. Our contributions are two folds: 1) a network termed Zoom-in-Net which mimics the zoom-in process of a clinician to examine the retinal images. Trained with only image-level supervisions, Zoomin-Net can generate attention maps which highlight suspicious regions, and predicts the disease level accurately based on both the whole image and its high resolution suspicious patches. 2) Only four bounding boxes generated from the automatically learned attention maps are enough to cover 80% of the lesions labeled by an experienced ophthalmologist, which shows good localization ability of the attention maps. By clustering features at high response locations on the attention maps, we discover meaningful clusters which contain potential lesions in diabetic retinopathy. Experiments show that our algorithm outperform the state-of-the-art methods on two datasets, EyePACS and Messidor.
[ { "version": "v1", "created": "Wed, 14 Jun 2017 09:13:52 GMT" } ]
2017-06-15T00:00:00
[ [ "Wang", "Zhe", "" ], [ "Yin", "Yanxin", "" ], [ "Shi", "Jianping", "" ], [ "Fang", "Wei", "" ], [ "Li", "Hongsheng", "" ], [ "Wang", "Xiaogang", "" ] ]
TITLE: Zoom-in-Net: Deep Mining Lesions for Diabetic Retinopathy Detection ABSTRACT: We propose a convolution neural network based algorithm for simultaneously diagnosing diabetic retinopathy and highlighting suspicious regions. Our contributions are two folds: 1) a network termed Zoom-in-Net which mimics the zoom-in process of a clinician to examine the retinal images. Trained with only image-level supervisions, Zoomin-Net can generate attention maps which highlight suspicious regions, and predicts the disease level accurately based on both the whole image and its high resolution suspicious patches. 2) Only four bounding boxes generated from the automatically learned attention maps are enough to cover 80% of the lesions labeled by an experienced ophthalmologist, which shows good localization ability of the attention maps. By clustering features at high response locations on the attention maps, we discover meaningful clusters which contain potential lesions in diabetic retinopathy. Experiments show that our algorithm outperform the state-of-the-art methods on two datasets, EyePACS and Messidor.
no_new_dataset
0.948822
1706.04399
Manh Duong Phung
Manh Duong Phung, Cong Hoang Quach, Tran Hiep Dinh, Quang Ha
Enhanced discrete particle swarm optimization path planning for UAV vision-based surface inspection
null
Automation in Construction, Vol.81, pp.25-33 (2017)
10.1016/j.autcon.2017.04.013
null
cs.RO cs.AI cs.CV
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
In built infrastructure monitoring, an efficient path planning algorithm is essential for robotic inspection of large surfaces using computer vision. In this work, we first formulate the inspection path planning problem as an extended travelling salesman problem (TSP) in which both the coverage and obstacle avoidance were taken into account. An enhanced discrete particle swarm optimization (DPSO) algorithm is then proposed to solve the TSP, with performance improvement by using deterministic initialization, random mutation, and edge exchange. Finally, we take advantage of parallel computing to implement the DPSO in a GPU-based framework so that the computation time can be significantly reduced while keeping the hardware requirement unchanged. To show the effectiveness of the proposed algorithm, experimental results are included for datasets obtained from UAV inspection of an office building and a bridge.
[ { "version": "v1", "created": "Wed, 14 Jun 2017 10:40:19 GMT" } ]
2017-06-15T00:00:00
[ [ "Phung", "Manh Duong", "" ], [ "Quach", "Cong Hoang", "" ], [ "Dinh", "Tran Hiep", "" ], [ "Ha", "Quang", "" ] ]
TITLE: Enhanced discrete particle swarm optimization path planning for UAV vision-based surface inspection ABSTRACT: In built infrastructure monitoring, an efficient path planning algorithm is essential for robotic inspection of large surfaces using computer vision. In this work, we first formulate the inspection path planning problem as an extended travelling salesman problem (TSP) in which both the coverage and obstacle avoidance were taken into account. An enhanced discrete particle swarm optimization (DPSO) algorithm is then proposed to solve the TSP, with performance improvement by using deterministic initialization, random mutation, and edge exchange. Finally, we take advantage of parallel computing to implement the DPSO in a GPU-based framework so that the computation time can be significantly reduced while keeping the hardware requirement unchanged. To show the effectiveness of the proposed algorithm, experimental results are included for datasets obtained from UAV inspection of an office building and a bridge.
no_new_dataset
0.947721
1706.04472
Prerana Mukherjee
Prerana Mukherjee, Brejesh Lall, Sarvaswa Tandon
SalProp: Salient object proposals via aggregated edge cues
5 pages, 4 figures, accepted at ICIP 2017
null
null
null
cs.CV
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
In this paper, we propose a novel object proposal generation scheme by formulating a graph-based salient edge classification framework that utilizes the edge context. In the proposed method, we construct a Bayesian probabilistic edge map to assign a saliency value to the edgelets by exploiting low level edge features. A Conditional Random Field is then learned to effectively combine these features for edge classification with object/non-object label. We propose an objectness score for the generated windows by analyzing the salient edge density inside the bounding box. Extensive experiments on PASCAL VOC 2007 dataset demonstrate that the proposed method gives competitive performance against 10 popular generic object detection techniques while using fewer number of proposals.
[ { "version": "v1", "created": "Wed, 14 Jun 2017 13:17:42 GMT" } ]
2017-06-15T00:00:00
[ [ "Mukherjee", "Prerana", "" ], [ "Lall", "Brejesh", "" ], [ "Tandon", "Sarvaswa", "" ] ]
TITLE: SalProp: Salient object proposals via aggregated edge cues ABSTRACT: In this paper, we propose a novel object proposal generation scheme by formulating a graph-based salient edge classification framework that utilizes the edge context. In the proposed method, we construct a Bayesian probabilistic edge map to assign a saliency value to the edgelets by exploiting low level edge features. A Conditional Random Field is then learned to effectively combine these features for edge classification with object/non-object label. We propose an objectness score for the generated windows by analyzing the salient edge density inside the bounding box. Extensive experiments on PASCAL VOC 2007 dataset demonstrate that the proposed method gives competitive performance against 10 popular generic object detection techniques while using fewer number of proposals.
no_new_dataset
0.948106
1706.04473
Kairit Sirts
Kairit Sirts, Olivier Piguet, Mark Johnson
Idea density for predicting Alzheimer's disease from transcribed speech
CoNLL 2017
null
null
null
cs.CL
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Idea Density (ID) measures the rate at which ideas or elementary predications are expressed in an utterance or in a text. Lower ID is found to be associated with an increased risk of developing Alzheimer's disease (AD) (Snowdon et al., 1996; Engelman et al., 2010). ID has been used in two different versions: propositional idea density (PID) counts the expressed ideas and can be applied to any text while semantic idea density (SID) counts pre-defined information content units and is naturally more applicable to normative domains, such as picture description tasks. In this paper, we develop DEPID, a novel dependency-based method for computing PID, and its version DEPID-R that enables to exclude repeating ideas---a feature characteristic to AD speech. We conduct the first comparison of automatically extracted PID and SID in the diagnostic classification task on two different AD datasets covering both closed-topic and free-recall domains. While SID performs better on the normative dataset, adding PID leads to a small but significant improvement (+1.7 F-score). On the free-topic dataset, PID performs better than SID as expected (77.6 vs 72.3 in F-score) but adding the features derived from the word embedding clustering underlying the automatic SID increases the results considerably, leading to an F-score of 84.8.
[ { "version": "v1", "created": "Wed, 14 Jun 2017 13:18:08 GMT" } ]
2017-06-15T00:00:00
[ [ "Sirts", "Kairit", "" ], [ "Piguet", "Olivier", "" ], [ "Johnson", "Mark", "" ] ]
TITLE: Idea density for predicting Alzheimer's disease from transcribed speech ABSTRACT: Idea Density (ID) measures the rate at which ideas or elementary predications are expressed in an utterance or in a text. Lower ID is found to be associated with an increased risk of developing Alzheimer's disease (AD) (Snowdon et al., 1996; Engelman et al., 2010). ID has been used in two different versions: propositional idea density (PID) counts the expressed ideas and can be applied to any text while semantic idea density (SID) counts pre-defined information content units and is naturally more applicable to normative domains, such as picture description tasks. In this paper, we develop DEPID, a novel dependency-based method for computing PID, and its version DEPID-R that enables to exclude repeating ideas---a feature characteristic to AD speech. We conduct the first comparison of automatically extracted PID and SID in the diagnostic classification task on two different AD datasets covering both closed-topic and free-recall domains. While SID performs better on the normative dataset, adding PID leads to a small but significant improvement (+1.7 F-score). On the free-topic dataset, PID performs better than SID as expected (77.6 vs 72.3 in F-score) but adding the features derived from the word embedding clustering underlying the automatic SID increases the results considerably, leading to an F-score of 84.8.
no_new_dataset
0.951142
1706.04488
Manuk Akopyan
Manuk Akopyan (1), and Eshsou Khashba (1) ((1) Institute for System Programming)
Large-Scale YouTube-8M Video Understanding with Deep Neural Networks
6 pages, 5 figures, 3 tables
null
null
null
cs.CV
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Video classification problem has been studied many years. The success of Convolutional Neural Networks (CNN) in image recognition tasks gives a powerful incentive for researchers to create more advanced video classification approaches. As video has a temporal content Long Short Term Memory (LSTM) networks become handy tool allowing to model long-term temporal clues. Both approaches need a large dataset of input data. In this paper three models provided to address video classification using recently announced YouTube-8M large-scale dataset. The first model is based on frame pooling approach. Two other models based on LSTM networks. Mixture of Experts intermediate layer is used in third model allowing to increase model capacity without dramatically increasing computations. The set of experiments for handling imbalanced training data has been conducted.
[ { "version": "v1", "created": "Wed, 14 Jun 2017 13:38:43 GMT" } ]
2017-06-15T00:00:00
[ [ "Akopyan", "Manuk", "" ], [ "Khashba", "Eshsou", "" ] ]
TITLE: Large-Scale YouTube-8M Video Understanding with Deep Neural Networks ABSTRACT: Video classification problem has been studied many years. The success of Convolutional Neural Networks (CNN) in image recognition tasks gives a powerful incentive for researchers to create more advanced video classification approaches. As video has a temporal content Long Short Term Memory (LSTM) networks become handy tool allowing to model long-term temporal clues. Both approaches need a large dataset of input data. In this paper three models provided to address video classification using recently announced YouTube-8M large-scale dataset. The first model is based on frame pooling approach. Two other models based on LSTM networks. Mixture of Experts intermediate layer is used in third model allowing to increase model capacity without dramatically increasing computations. The set of experiments for handling imbalanced training data has been conducted.
no_new_dataset
0.94868
1706.04525
Giulio Siracusano Dr.
Giulio Siracusano, Aurelio La Corte, Michele Gaeta, Giovanni Finocchio
A data-Oriented based Self-Calibration And Robust chemical-shift encoding by using clusterization (OSCAR) - Theory, Optimization and Clinical Validation in Neuromuscular disorders
29 pages and 11 images as supplemental materials
null
null
null
physics.med-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Multi-echo Chemical Shift Encoded methods for Fat-Water quantification are growing in clinical use due to their ability to estimate and correct some confounding effects. State of the art CSE water-fat separation approaches rely on a multi-peak fat spectrum with peak frequencies and relative amplitudes kept constant over the entire MRI dataset. However, the latter approximation introduces a systematic error in fat percentage quantification in patients where the differences in lipid chemical composition are significant, such as for neuromuscular disorders, because of the spatial dependence of the peak amplitudes. The present work aims to overcome this limitation by taking advantage of an unsupervised clusterization-based approach offering a reliable criterion to carry out a data-driven segmentation of the input MRI dataset into multiple regions. The idea is to apply the clusterization for partitioning the multi-echo MRI dataset into a finite number of clusters whose internal voxels exhibit similar distance metrics. For each cluster, the estimation of the fat spectral properties are evaluated with a self-calibration technique and finally the fat-water percentages are computed via a non-linear fitting. The method is tested in ad-hoc and public datasets. The overall performance and results in terms of fitting accuracy, robustness and reproducibility are compared with other state-of-the-art CSE algorithms. This approach provides a more accurate and reproducible identification of chemical species, hence fat-water separation, when compared with other calibrated and non-calibrated approaches.
[ { "version": "v1", "created": "Wed, 14 Jun 2017 15:02:44 GMT" } ]
2017-06-15T00:00:00
[ [ "Siracusano", "Giulio", "" ], [ "La Corte", "Aurelio", "" ], [ "Gaeta", "Michele", "" ], [ "Finocchio", "Giovanni", "" ] ]
TITLE: A data-Oriented based Self-Calibration And Robust chemical-shift encoding by using clusterization (OSCAR) - Theory, Optimization and Clinical Validation in Neuromuscular disorders ABSTRACT: Multi-echo Chemical Shift Encoded methods for Fat-Water quantification are growing in clinical use due to their ability to estimate and correct some confounding effects. State of the art CSE water-fat separation approaches rely on a multi-peak fat spectrum with peak frequencies and relative amplitudes kept constant over the entire MRI dataset. However, the latter approximation introduces a systematic error in fat percentage quantification in patients where the differences in lipid chemical composition are significant, such as for neuromuscular disorders, because of the spatial dependence of the peak amplitudes. The present work aims to overcome this limitation by taking advantage of an unsupervised clusterization-based approach offering a reliable criterion to carry out a data-driven segmentation of the input MRI dataset into multiple regions. The idea is to apply the clusterization for partitioning the multi-echo MRI dataset into a finite number of clusters whose internal voxels exhibit similar distance metrics. For each cluster, the estimation of the fat spectral properties are evaluated with a self-calibration technique and finally the fat-water percentages are computed via a non-linear fitting. The method is tested in ad-hoc and public datasets. The overall performance and results in terms of fitting accuracy, robustness and reproducibility are compared with other state-of-the-art CSE algorithms. This approach provides a more accurate and reproducible identification of chemical species, hence fat-water separation, when compared with other calibrated and non-calibrated approaches.
no_new_dataset
0.951774
1706.04572
Miha Skalic
Miha Skalic, Marcin Pekalski, Xingguo E. Pan
Deep Learning Methods for Efficient Large Scale Video Labeling
7 pages, 5 tables, 1 figure
null
null
null
stat.ML cs.CV cs.LG
http://creativecommons.org/licenses/by/4.0/
We present a solution to "Google Cloud and YouTube-8M Video Understanding Challenge" that ranked 5th place. The proposed model is an ensemble of three model families, two frame level and one video level. The training was performed on augmented dataset, with cross validation.
[ { "version": "v1", "created": "Wed, 14 Jun 2017 16:24:18 GMT" } ]
2017-06-15T00:00:00
[ [ "Skalic", "Miha", "" ], [ "Pekalski", "Marcin", "" ], [ "Pan", "Xingguo E.", "" ] ]
TITLE: Deep Learning Methods for Efficient Large Scale Video Labeling ABSTRACT: We present a solution to "Google Cloud and YouTube-8M Video Understanding Challenge" that ranked 5th place. The proposed model is an ensemble of three model families, two frame level and one video level. The training was performed on augmented dataset, with cross validation.
no_new_dataset
0.952662
1609.06377
Reza Mahjourian
Reza Mahjourian, Martin Wicke, Anelia Angelova
Geometry-Based Next Frame Prediction from Monocular Video
To appear in 2017 IEEE Intelligent Vehicles Symposium
null
null
null
cs.LG cs.CV
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We consider the problem of next frame prediction from video input. A recurrent convolutional neural network is trained to predict depth from monocular video input, which, along with the current video image and the camera trajectory, can then be used to compute the next frame. Unlike prior next-frame prediction approaches, we take advantage of the scene geometry and use the predicted depth for generating the next frame prediction. Our approach can produce rich next frame predictions which include depth information attached to each pixel. Another novel aspect of our approach is that it predicts depth from a sequence of images (e.g. in a video), rather than from a single still image. We evaluate the proposed approach on the KITTI dataset, a standard dataset for benchmarking tasks relevant to autonomous driving. The proposed method produces results which are visually and numerically superior to existing methods that directly predict the next frame. We show that the accuracy of depth prediction improves as more prior frames are considered.
[ { "version": "v1", "created": "Tue, 20 Sep 2016 22:49:34 GMT" }, { "version": "v2", "created": "Mon, 12 Jun 2017 21:52:06 GMT" } ]
2017-06-14T00:00:00
[ [ "Mahjourian", "Reza", "" ], [ "Wicke", "Martin", "" ], [ "Angelova", "Anelia", "" ] ]
TITLE: Geometry-Based Next Frame Prediction from Monocular Video ABSTRACT: We consider the problem of next frame prediction from video input. A recurrent convolutional neural network is trained to predict depth from monocular video input, which, along with the current video image and the camera trajectory, can then be used to compute the next frame. Unlike prior next-frame prediction approaches, we take advantage of the scene geometry and use the predicted depth for generating the next frame prediction. Our approach can produce rich next frame predictions which include depth information attached to each pixel. Another novel aspect of our approach is that it predicts depth from a sequence of images (e.g. in a video), rather than from a single still image. We evaluate the proposed approach on the KITTI dataset, a standard dataset for benchmarking tasks relevant to autonomous driving. The proposed method produces results which are visually and numerically superior to existing methods that directly predict the next frame. We show that the accuracy of depth prediction improves as more prior frames are considered.
no_new_dataset
0.952397
1612.09548
Zhenhua Feng
Zhen-Hua Feng, Josef Kittler, William Christmas and Xiao-Jun Wu
A Unified Tensor-based Active Appearance Face Model
null
null
null
null
cs.CV
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Appearance variations result in many difficulties in face image analysis. To deal with this challenge, we present a Unified Tensor-based Active Appearance Model (UT-AAM) for jointly modelling the geometry and texture information of 2D faces. For each type of face information, namely shape and texture, we construct a unified tensor model capturing all relevant appearance variations. This contrasts with the variation-specific models of the classical tensor AAM. To achieve the unification across pose variations, a strategy for dealing with self-occluded faces is proposed to obtain consistent shape and texture representations of pose-varied faces. In addition, our UT-AAM is capable of constructing the model from an incomplete training dataset, using tensor completion methods. Last, we use an effective cascaded-regression-based method for UT-AAM fitting. With these advancements, the utility of UT-AAM in practice is considerably enhanced. As an example, we demonstrate the improvements in training facial landmark detectors through the use of UT-AAM to synthesise a large number of virtual samples. Experimental results obtained using the Multi-PIE and 300-W face datasets demonstrate the merits of the proposed approach.
[ { "version": "v1", "created": "Fri, 30 Dec 2016 18:08:16 GMT" }, { "version": "v2", "created": "Tue, 13 Jun 2017 16:33:25 GMT" } ]
2017-06-14T00:00:00
[ [ "Feng", "Zhen-Hua", "" ], [ "Kittler", "Josef", "" ], [ "Christmas", "William", "" ], [ "Wu", "Xiao-Jun", "" ] ]
TITLE: A Unified Tensor-based Active Appearance Face Model ABSTRACT: Appearance variations result in many difficulties in face image analysis. To deal with this challenge, we present a Unified Tensor-based Active Appearance Model (UT-AAM) for jointly modelling the geometry and texture information of 2D faces. For each type of face information, namely shape and texture, we construct a unified tensor model capturing all relevant appearance variations. This contrasts with the variation-specific models of the classical tensor AAM. To achieve the unification across pose variations, a strategy for dealing with self-occluded faces is proposed to obtain consistent shape and texture representations of pose-varied faces. In addition, our UT-AAM is capable of constructing the model from an incomplete training dataset, using tensor completion methods. Last, we use an effective cascaded-regression-based method for UT-AAM fitting. With these advancements, the utility of UT-AAM in practice is considerably enhanced. As an example, we demonstrate the improvements in training facial landmark detectors through the use of UT-AAM to synthesise a large number of virtual samples. Experimental results obtained using the Multi-PIE and 300-W face datasets demonstrate the merits of the proposed approach.
no_new_dataset
0.948155
1701.00193
Hao Liu
Hao Liu, Zequn Jie, Karlekar Jayashree, Meibin Qi, Jianguo Jiang, Shuicheng Yan, Jiashi Feng
Video-based Person Re-identification with Accumulative Motion Context
accepted by TCSVT
null
null
null
cs.CV
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Video based person re-identification plays a central role in realistic security and video surveillance. In this paper we propose a novel Accumulative Motion Context (AMOC) network for addressing this important problem, which effectively exploits the long-range motion context for robustly identifying the same person under challenging conditions. Given a video sequence of the same or different persons, the proposed AMOC network jointly learns appearance representation and motion context from a collection of adjacent frames using a two-stream convolutional architecture. Then AMOC accumulates clues from motion context by recurrent aggregation, allowing effective information flow among adjacent frames and capturing dynamic gist of the persons. The architecture of AMOC is end-to-end trainable and thus motion context can be adapted to complement appearance clues under unfavorable conditions (e.g. occlusions). Extensive experiments are conduced on three public benchmark datasets, i.e., the iLIDS-VID, PRID-2011 and MARS datasets, to investigate the performance of AMOC. The experimental results demonstrate that the proposed AMOC network outperforms state-of-the-arts for video-based re-identification significantly and confirm the advantage of exploiting long-range motion context for video based person re-identification, validating our motivation evidently.
[ { "version": "v1", "created": "Sun, 1 Jan 2017 04:20:20 GMT" }, { "version": "v2", "created": "Tue, 13 Jun 2017 03:27:01 GMT" } ]
2017-06-14T00:00:00
[ [ "Liu", "Hao", "" ], [ "Jie", "Zequn", "" ], [ "Jayashree", "Karlekar", "" ], [ "Qi", "Meibin", "" ], [ "Jiang", "Jianguo", "" ], [ "Yan", "Shuicheng", "" ], [ "Feng", "Jiashi", "" ] ]
TITLE: Video-based Person Re-identification with Accumulative Motion Context ABSTRACT: Video based person re-identification plays a central role in realistic security and video surveillance. In this paper we propose a novel Accumulative Motion Context (AMOC) network for addressing this important problem, which effectively exploits the long-range motion context for robustly identifying the same person under challenging conditions. Given a video sequence of the same or different persons, the proposed AMOC network jointly learns appearance representation and motion context from a collection of adjacent frames using a two-stream convolutional architecture. Then AMOC accumulates clues from motion context by recurrent aggregation, allowing effective information flow among adjacent frames and capturing dynamic gist of the persons. The architecture of AMOC is end-to-end trainable and thus motion context can be adapted to complement appearance clues under unfavorable conditions (e.g. occlusions). Extensive experiments are conduced on three public benchmark datasets, i.e., the iLIDS-VID, PRID-2011 and MARS datasets, to investigate the performance of AMOC. The experimental results demonstrate that the proposed AMOC network outperforms state-of-the-arts for video-based re-identification significantly and confirm the advantage of exploiting long-range motion context for video based person re-identification, validating our motivation evidently.
no_new_dataset
0.951863
1701.02405
Juan Echeverria
Juan Echeverr\'ia, Shi Zhou
Discovery, Retrieval, and Analysis of 'Star Wars' botnet in Twitter
Accepted for publication at ASONAM 2017
null
null
null
cs.SI
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
It is known that many Twitter users are bots, which are accounts controlled and sometimes created by computers. Twitter bots can send spam tweets, manipulate public opinion and be used for online fraud. Here we report the discovery, retrieval, and analysis of the `Star Wars' botnet in Twitter, which consists of more than 350,000 bots tweeting random quotations exclusively from Star Wars novels. The botnet contains a single type of bot, showing exactly the same properties throughout the botnet. It is unusually large, many times larger than other available datasets. It provides a valuable source of ground truth for research on Twitter bots. We analysed and revealed rich details on how the botnet was designed and created. As of this writing, the Star Wars bots are still alive in Twitter. They have survived since their creation in 2013, despite the increasing efforts in recent years to detect and remove Twitter bots.We also reflect on the `unconventional' way in which we discovered the Star Wars bots, and discuss the current problems and future challenges of Twitter bot detection.
[ { "version": "v1", "created": "Tue, 10 Jan 2017 01:56:03 GMT" }, { "version": "v2", "created": "Wed, 26 Apr 2017 04:14:28 GMT" }, { "version": "v3", "created": "Tue, 13 Jun 2017 13:47:08 GMT" } ]
2017-06-14T00:00:00
[ [ "Echeverría", "Juan", "" ], [ "Zhou", "Shi", "" ] ]
TITLE: Discovery, Retrieval, and Analysis of 'Star Wars' botnet in Twitter ABSTRACT: It is known that many Twitter users are bots, which are accounts controlled and sometimes created by computers. Twitter bots can send spam tweets, manipulate public opinion and be used for online fraud. Here we report the discovery, retrieval, and analysis of the `Star Wars' botnet in Twitter, which consists of more than 350,000 bots tweeting random quotations exclusively from Star Wars novels. The botnet contains a single type of bot, showing exactly the same properties throughout the botnet. It is unusually large, many times larger than other available datasets. It provides a valuable source of ground truth for research on Twitter bots. We analysed and revealed rich details on how the botnet was designed and created. As of this writing, the Star Wars bots are still alive in Twitter. They have survived since their creation in 2013, despite the increasing efforts in recent years to detect and remove Twitter bots.We also reflect on the `unconventional' way in which we discovered the Star Wars bots, and discuss the current problems and future challenges of Twitter bot detection.
no_new_dataset
0.928018
1703.06337
Andriy Miranskyy
Mefta Sadat and Ayse Basar Bener and Andriy V. Miranskyy
Rediscovery Datasets: Connecting Duplicate Reports
null
Proceedings of the 14th International Conference on Mining Software Repositories (MSR '17). IEEE Press, Piscataway, NJ, USA, 527-530, 2017
10.1109/MSR.2017.50
null
cs.SE
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The same defect can be rediscovered by multiple clients, causing unplanned outages and leading to reduced customer satisfaction. In the case of popular open source software, high volume of defects is reported on a regular basis. A large number of these reports are actually duplicates / rediscoveries of each other. Researchers have analyzed the factors related to the content of duplicate defect reports in the past. However, some of the other potentially important factors, such as the inter-relationships among duplicate defect reports, are not readily available in defect tracking systems such as Bugzilla. This information may speed up bug fixing, enable efficient triaging, improve customer profiles, etc. In this paper, we present three defect rediscovery datasets mined from Bugzilla. The datasets capture data for three groups of open source software projects: Apache, Eclipse, and KDE. The datasets contain information about approximately 914 thousands of defect reports over a period of 18 years (1999-2017) to capture the inter-relationships among duplicate defects. We believe that sharing these data with the community will help researchers and practitioners to better understand the nature of defect rediscovery and enhance the analysis of defect reports.
[ { "version": "v1", "created": "Sat, 18 Mar 2017 19:01:38 GMT" } ]
2017-06-14T00:00:00
[ [ "Sadat", "Mefta", "" ], [ "Bener", "Ayse Basar", "" ], [ "Miranskyy", "Andriy V.", "" ] ]
TITLE: Rediscovery Datasets: Connecting Duplicate Reports ABSTRACT: The same defect can be rediscovered by multiple clients, causing unplanned outages and leading to reduced customer satisfaction. In the case of popular open source software, high volume of defects is reported on a regular basis. A large number of these reports are actually duplicates / rediscoveries of each other. Researchers have analyzed the factors related to the content of duplicate defect reports in the past. However, some of the other potentially important factors, such as the inter-relationships among duplicate defect reports, are not readily available in defect tracking systems such as Bugzilla. This information may speed up bug fixing, enable efficient triaging, improve customer profiles, etc. In this paper, we present three defect rediscovery datasets mined from Bugzilla. The datasets capture data for three groups of open source software projects: Apache, Eclipse, and KDE. The datasets contain information about approximately 914 thousands of defect reports over a period of 18 years (1999-2017) to capture the inter-relationships among duplicate defects. We believe that sharing these data with the community will help researchers and practitioners to better understand the nature of defect rediscovery and enhance the analysis of defect reports.
new_dataset
0.960768
1704.00551
Shuai Zhang
Shuai Zhang, Lina Yao and Xiwei Xu
AutoSVD++: An Efficient Hybrid Collaborative Filtering Model via Contractive Auto-encoders
4 pages, 3 figures
null
10.1145/3077136.3080689
null
cs.IR
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Collaborative filtering (CF) has been successfully used to provide users with personalized products and services. However, dealing with the increasing sparseness of user-item matrix still remains a challenge. To tackle such issue, hybrid CF such as combining with content based filtering and leveraging side information of users and items has been extensively studied to enhance performance. However, most of these approaches depend on hand-crafted feature engineering, which are usually noise-prone and biased by different feature extraction and selection schemes. In this paper, we propose a new hybrid model by generalizing contractive auto-encoder paradigm into matrix factorization framework with good scalability and computational efficiency, which jointly model content information as representations of effectiveness and compactness, and leverage implicit user feedback to make accurate recommendations. Extensive experiments conducted over three large scale real datasets indicate the proposed approach outperforms the compared methods for item recommendation.
[ { "version": "v1", "created": "Mon, 3 Apr 2017 12:39:25 GMT" }, { "version": "v2", "created": "Tue, 2 May 2017 00:17:14 GMT" }, { "version": "v3", "created": "Tue, 13 Jun 2017 01:01:30 GMT" } ]
2017-06-14T00:00:00
[ [ "Zhang", "Shuai", "" ], [ "Yao", "Lina", "" ], [ "Xu", "Xiwei", "" ] ]
TITLE: AutoSVD++: An Efficient Hybrid Collaborative Filtering Model via Contractive Auto-encoders ABSTRACT: Collaborative filtering (CF) has been successfully used to provide users with personalized products and services. However, dealing with the increasing sparseness of user-item matrix still remains a challenge. To tackle such issue, hybrid CF such as combining with content based filtering and leveraging side information of users and items has been extensively studied to enhance performance. However, most of these approaches depend on hand-crafted feature engineering, which are usually noise-prone and biased by different feature extraction and selection schemes. In this paper, we propose a new hybrid model by generalizing contractive auto-encoder paradigm into matrix factorization framework with good scalability and computational efficiency, which jointly model content information as representations of effectiveness and compactness, and leverage implicit user feedback to make accurate recommendations. Extensive experiments conducted over three large scale real datasets indicate the proposed approach outperforms the compared methods for item recommendation.
no_new_dataset
0.943191
1704.01212
Justin Gilmer
Justin Gilmer, Samuel S. Schoenholz, Patrick F. Riley, Oriol Vinyals, George E. Dahl
Neural Message Passing for Quantum Chemistry
14 pages
null
null
null
cs.LG
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Supervised learning on molecules has incredible potential to be useful in chemistry, drug discovery, and materials science. Luckily, several promising and closely related neural network models invariant to molecular symmetries have already been described in the literature. These models learn a message passing algorithm and aggregation procedure to compute a function of their entire input graph. At this point, the next step is to find a particularly effective variant of this general approach and apply it to chemical prediction benchmarks until we either solve them or reach the limits of the approach. In this paper, we reformulate existing models into a single common framework we call Message Passing Neural Networks (MPNNs) and explore additional novel variations within this framework. Using MPNNs we demonstrate state of the art results on an important molecular property prediction benchmark; these results are strong enough that we believe future work should focus on datasets with larger molecules or more accurate ground truth labels.
[ { "version": "v1", "created": "Tue, 4 Apr 2017 23:00:44 GMT" }, { "version": "v2", "created": "Mon, 12 Jun 2017 20:52:56 GMT" } ]
2017-06-14T00:00:00
[ [ "Gilmer", "Justin", "" ], [ "Schoenholz", "Samuel S.", "" ], [ "Riley", "Patrick F.", "" ], [ "Vinyals", "Oriol", "" ], [ "Dahl", "George E.", "" ] ]
TITLE: Neural Message Passing for Quantum Chemistry ABSTRACT: Supervised learning on molecules has incredible potential to be useful in chemistry, drug discovery, and materials science. Luckily, several promising and closely related neural network models invariant to molecular symmetries have already been described in the literature. These models learn a message passing algorithm and aggregation procedure to compute a function of their entire input graph. At this point, the next step is to find a particularly effective variant of this general approach and apply it to chemical prediction benchmarks until we either solve them or reach the limits of the approach. In this paper, we reformulate existing models into a single common framework we call Message Passing Neural Networks (MPNNs) and explore additional novel variations within this framework. Using MPNNs we demonstrate state of the art results on an important molecular property prediction benchmark; these results are strong enough that we believe future work should focus on datasets with larger molecules or more accurate ground truth labels.
no_new_dataset
0.947088
1704.05645
Bo Li
Bo Li, Mingyi He, Xuelian Cheng, Yucheng Chen, Yuchao Dai
Skeleton based action recognition using translation-scale invariant image mapping and multi-scale deep cnn
null
null
null
null
cs.CV
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
This paper presents an image classification based approach for skeleton-based video action recognition problem. Firstly, A dataset independent translation-scale invariant image mapping method is proposed, which transformes the skeleton videos to colour images, named skeleton-images. Secondly, A multi-scale deep convolutional neural network (CNN) architecture is proposed which could be built and fine-tuned on the powerful pre-trained CNNs, e.g., AlexNet, VGGNet, ResNet etal.. Even though the skeleton-images are very different from natural images, the fine-tune strategy still works well. At last, we prove that our method could also work well on 2D skeleton video data. We achieve the state-of-the-art results on the popular benchmard datasets e.g. NTU RGB+D, UTD-MHAD, MSRC-12, and G3D. Especially on the largest and challenge NTU RGB+D, UTD-MHAD, and MSRC-12 dataset, our method outperforms other methods by a large margion, which proves the efficacy of the proposed method.
[ { "version": "v1", "created": "Wed, 19 Apr 2017 08:30:19 GMT" }, { "version": "v2", "created": "Tue, 13 Jun 2017 01:59:13 GMT" } ]
2017-06-14T00:00:00
[ [ "Li", "Bo", "" ], [ "He", "Mingyi", "" ], [ "Cheng", "Xuelian", "" ], [ "Chen", "Yucheng", "" ], [ "Dai", "Yuchao", "" ] ]
TITLE: Skeleton based action recognition using translation-scale invariant image mapping and multi-scale deep cnn ABSTRACT: This paper presents an image classification based approach for skeleton-based video action recognition problem. Firstly, A dataset independent translation-scale invariant image mapping method is proposed, which transformes the skeleton videos to colour images, named skeleton-images. Secondly, A multi-scale deep convolutional neural network (CNN) architecture is proposed which could be built and fine-tuned on the powerful pre-trained CNNs, e.g., AlexNet, VGGNet, ResNet etal.. Even though the skeleton-images are very different from natural images, the fine-tune strategy still works well. At last, we prove that our method could also work well on 2D skeleton video data. We achieve the state-of-the-art results on the popular benchmard datasets e.g. NTU RGB+D, UTD-MHAD, MSRC-12, and G3D. Especially on the largest and challenge NTU RGB+D, UTD-MHAD, and MSRC-12 dataset, our method outperforms other methods by a large margion, which proves the efficacy of the proposed method.
no_new_dataset
0.949763
1706.02777
R.Stuart Geiger
R. Stuart Geiger
Summary Analysis of the 2017 GitHub Open Source Survey
58 pages
null
10.17605/OSF.IO/ENRQ5
null
cs.CY cs.SE cs.SI
http://creativecommons.org/licenses/by/4.0/
This report is a high-level summary analysis of the 2017 GitHub Open Source Survey dataset, presenting frequency counts, proportions, and frequency or proportion bar plots for every question asked in the survey.
[ { "version": "v1", "created": "Thu, 8 Jun 2017 21:29:00 GMT" } ]
2017-06-14T00:00:00
[ [ "Geiger", "R. Stuart", "" ] ]
TITLE: Summary Analysis of the 2017 GitHub Open Source Survey ABSTRACT: This report is a high-level summary analysis of the 2017 GitHub Open Source Survey dataset, presenting frequency counts, proportions, and frequency or proportion bar plots for every question asked in the survey.
no_new_dataset
0.96738
1706.03863
Kwang In Kim
James Tompkin, Kwang In Kim, Hanspeter Pfister and Christian Theobalt
Criteria Sliders: Learning Continuous Database Criteria via Interactive Ranking
null
null
null
null
cs.CV
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Large databases are often organized by hand-labeled metadata, or criteria, which are expensive to collect. We can use unsupervised learning to model database variation, but these models are often high dimensional, complex to parameterize, or require expert knowledge. We learn low-dimensional continuous criteria via interactive ranking, so that the novice user need only describe the relative ordering of examples. This is formed as semi-supervised label propagation in which we maximize the information gained from a limited number of examples. Further, we actively suggest data points to the user to rank in a more informative way than existing work. Our efficient approach allows users to interactively organize thousands of data points along 1D and 2D continuous sliders. We experiment with datasets of imagery and geometry to demonstrate that our tool is useful for quickly assessing and organizing the content of large databases.
[ { "version": "v1", "created": "Mon, 12 Jun 2017 21:59:26 GMT" } ]
2017-06-14T00:00:00
[ [ "Tompkin", "James", "" ], [ "Kim", "Kwang In", "" ], [ "Pfister", "Hanspeter", "" ], [ "Theobalt", "Christian", "" ] ]
TITLE: Criteria Sliders: Learning Continuous Database Criteria via Interactive Ranking ABSTRACT: Large databases are often organized by hand-labeled metadata, or criteria, which are expensive to collect. We can use unsupervised learning to model database variation, but these models are often high dimensional, complex to parameterize, or require expert knowledge. We learn low-dimensional continuous criteria via interactive ranking, so that the novice user need only describe the relative ordering of examples. This is formed as semi-supervised label propagation in which we maximize the information gained from a limited number of examples. Further, we actively suggest data points to the user to rank in a more informative way than existing work. Our efficient approach allows users to interactively organize thousands of data points along 1D and 2D continuous sliders. We experiment with datasets of imagery and geometry to demonstrate that our tool is useful for quickly assessing and organizing the content of large databases.
no_new_dataset
0.953708
1706.03946
Isabelle Augenstein
Ed Collins and Isabelle Augenstein and Sebastian Riedel
A Supervised Approach to Extractive Summarisation of Scientific Papers
11 pages, 6 figures
null
null
null
cs.CL cs.AI cs.NE stat.AP stat.ML
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Automatic summarisation is a popular approach to reduce a document to its main arguments. Recent research in the area has focused on neural approaches to summarisation, which can be very data-hungry. However, few large datasets exist and none for the traditionally popular domain of scientific publications, which opens up challenging research avenues centered on encoding large, complex documents. In this paper, we introduce a new dataset for summarisation of computer science publications by exploiting a large resource of author provided summaries and show straightforward ways of extending it further. We develop models on the dataset making use of both neural sentence encoding and traditionally used summarisation features and show that models which encode sentences as well as their local and global context perform best, significantly outperforming well-established baseline methods.
[ { "version": "v1", "created": "Tue, 13 Jun 2017 08:15:25 GMT" } ]
2017-06-14T00:00:00
[ [ "Collins", "Ed", "" ], [ "Augenstein", "Isabelle", "" ], [ "Riedel", "Sebastian", "" ] ]
TITLE: A Supervised Approach to Extractive Summarisation of Scientific Papers ABSTRACT: Automatic summarisation is a popular approach to reduce a document to its main arguments. Recent research in the area has focused on neural approaches to summarisation, which can be very data-hungry. However, few large datasets exist and none for the traditionally popular domain of scientific publications, which opens up challenging research avenues centered on encoding large, complex documents. In this paper, we introduce a new dataset for summarisation of computer science publications by exploiting a large resource of author provided summaries and show straightforward ways of extending it further. We develop models on the dataset making use of both neural sentence encoding and traditionally used summarisation features and show that models which encode sentences as well as their local and global context perform best, significantly outperforming well-established baseline methods.
new_dataset
0.957873
1706.04026
Panayiotis Christodoulou
Sotirios Chatzis, Panayiotis Christodoulou, Andreas S. Andreou
Recurrent Latent Variable Networks for Session-Based Recommendation
null
null
null
null
cs.IR cs.LG stat.ML
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
In this work, we attempt to ameliorate the impact of data sparsity in the context of session-based recommendation. Specifically, we seek to devise a machine learning mechanism capable of extracting subtle and complex underlying temporal dynamics in the observed session data, so as to inform the recommendation algorithm. To this end, we improve upon systems that utilize deep learning techniques with recurrently connected units; we do so by adopting concepts from the field of Bayesian statistics, namely variational inference. Our proposed approach consists in treating the network recurrent units as stochastic latent variables with a prior distribution imposed over them. On this basis, we proceed to infer corresponding posteriors; these can be used for prediction and recommendation generation, in a way that accounts for the uncertainty in the available sparse training data. To allow for our approach to easily scale to large real-world datasets, we perform inference under an approximate amortized variational inference (AVI) setup, whereby the learned posteriors are parameterized via (conventional) neural networks. We perform an extensive experimental evaluation of our approach using challenging benchmark datasets, and illustrate its superiority over existing state-of-the-art techniques.
[ { "version": "v1", "created": "Tue, 13 Jun 2017 12:35:56 GMT" } ]
2017-06-14T00:00:00
[ [ "Chatzis", "Sotirios", "" ], [ "Christodoulou", "Panayiotis", "" ], [ "Andreou", "Andreas S.", "" ] ]
TITLE: Recurrent Latent Variable Networks for Session-Based Recommendation ABSTRACT: In this work, we attempt to ameliorate the impact of data sparsity in the context of session-based recommendation. Specifically, we seek to devise a machine learning mechanism capable of extracting subtle and complex underlying temporal dynamics in the observed session data, so as to inform the recommendation algorithm. To this end, we improve upon systems that utilize deep learning techniques with recurrently connected units; we do so by adopting concepts from the field of Bayesian statistics, namely variational inference. Our proposed approach consists in treating the network recurrent units as stochastic latent variables with a prior distribution imposed over them. On this basis, we proceed to infer corresponding posteriors; these can be used for prediction and recommendation generation, in a way that accounts for the uncertainty in the available sparse training data. To allow for our approach to easily scale to large real-world datasets, we perform inference under an approximate amortized variational inference (AVI) setup, whereby the learned posteriors are parameterized via (conventional) neural networks. We perform an extensive experimental evaluation of our approach using challenging benchmark datasets, and illustrate its superiority over existing state-of-the-art techniques.
no_new_dataset
0.943867
1706.04047
Mikko Rinne
Mikko Rinne, Mehrdad Bagheri, Tuukka Tolvanen
Automatic Recognition of Public Transport Trips from Mobile Device Sensor Data and Transport Infrastructure Information
22 pages, 7 figures, 10 tables
null
null
null
cs.CY
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Automatic detection of public transport (PT) usage has important applications for intelligent transport systems. It is crucial for understanding the commuting habits of passengers at large and over longer periods of time. It also enables compilation of door-to-door trip chains, which in turn can assist public transport providers in improved optimisation of their transport networks. In addition, predictions of future trips based on past activities can be used to assist passengers with targeted information. This article documents a dataset compiled from a day of active commuting by a small group of people using different means of PT in the Helsinki region. Mobility data was collected by two means: (a) manually written details of each PT trip during the day, and (b) measurements using sensors of travellers' mobile devices. The manual log is used to cross-check and verify the results derived from automatic measurements. The mobile client application used for our data collection provides a fully automated measurement service and implements a set of algorithms for decreasing battery consumption. The live locations of some of the public transport vehicles in the region were made available by the local transport provider and sampled with a 30-second interval. The stopping times of local trains at stations during the day were retrieved from the railway operator. The static timetable information of all the PT vehicles operating in the area is made available by the transport provider, and linked to our dataset. The challenge is to correctly detect as many manually logged trips as possible by using the automatically collected data. This paper includes an analysis of challenges due to missing or partially sampled information in the data, and initial results from automatic recognition using a set of algorithms. Improvement of correct recognitions is left as an ongoing challenge.
[ { "version": "v1", "created": "Tue, 13 Jun 2017 13:19:43 GMT" } ]
2017-06-14T00:00:00
[ [ "Rinne", "Mikko", "" ], [ "Bagheri", "Mehrdad", "" ], [ "Tolvanen", "Tuukka", "" ] ]
TITLE: Automatic Recognition of Public Transport Trips from Mobile Device Sensor Data and Transport Infrastructure Information ABSTRACT: Automatic detection of public transport (PT) usage has important applications for intelligent transport systems. It is crucial for understanding the commuting habits of passengers at large and over longer periods of time. It also enables compilation of door-to-door trip chains, which in turn can assist public transport providers in improved optimisation of their transport networks. In addition, predictions of future trips based on past activities can be used to assist passengers with targeted information. This article documents a dataset compiled from a day of active commuting by a small group of people using different means of PT in the Helsinki region. Mobility data was collected by two means: (a) manually written details of each PT trip during the day, and (b) measurements using sensors of travellers' mobile devices. The manual log is used to cross-check and verify the results derived from automatic measurements. The mobile client application used for our data collection provides a fully automated measurement service and implements a set of algorithms for decreasing battery consumption. The live locations of some of the public transport vehicles in the region were made available by the local transport provider and sampled with a 30-second interval. The stopping times of local trains at stations during the day were retrieved from the railway operator. The static timetable information of all the PT vehicles operating in the area is made available by the transport provider, and linked to our dataset. The challenge is to correctly detect as many manually logged trips as possible by using the automatically collected data. This paper includes an analysis of challenges due to missing or partially sampled information in the data, and initial results from automatic recognition using a set of algorithms. Improvement of correct recognitions is left as an ongoing challenge.
no_new_dataset
0.834879
1706.04052
Jinzhuo Wang
Jinzhuo Wang, Wenmin Wang, Ronggang Wang, Wen Gao
Beyond Monte Carlo Tree Search: Playing Go with Deep Alternative Neural Network and Long-Term Evaluation
AAAI 2017
null
null
null
cs.AI cs.LG cs.NE
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Monte Carlo tree search (MCTS) is extremely popular in computer Go which determines each action by enormous simulations in a broad and deep search tree. However, human experts select most actions by pattern analysis and careful evaluation rather than brute search of millions of future nteractions. In this paper, we propose a computer Go system that follows experts way of thinking and playing. Our system consists of two parts. The first part is a novel deep alternative neural network (DANN) used to generate candidates of next move. Compared with existing deep convolutional neural network (DCNN), DANN inserts recurrent layer after each convolutional layer and stacks them in an alternative manner. We show such setting can preserve more contexts of local features and its evolutions which are beneficial for move prediction. The second part is a long-term evaluation (LTE) module used to provide a reliable evaluation of candidates rather than a single probability from move predictor. This is consistent with human experts nature of playing since they can foresee tens of steps to give an accurate estimation of candidates. In our system, for each candidate, LTE calculates a cumulative reward after several future interactions when local variations are settled. Combining criteria from the two parts, our system determines the optimal choice of next move. For more comprehensive experiments, we introduce a new professional Go dataset (PGD), consisting of 253233 professional records. Experiments on GoGoD and PGD datasets show the DANN can substantially improve performance of move prediction over pure DCNN. When combining LTE, our system outperforms most relevant approaches and open engines based on MCTS.
[ { "version": "v1", "created": "Tue, 13 Jun 2017 13:30:04 GMT" } ]
2017-06-14T00:00:00
[ [ "Wang", "Jinzhuo", "" ], [ "Wang", "Wenmin", "" ], [ "Wang", "Ronggang", "" ], [ "Gao", "Wen", "" ] ]
TITLE: Beyond Monte Carlo Tree Search: Playing Go with Deep Alternative Neural Network and Long-Term Evaluation ABSTRACT: Monte Carlo tree search (MCTS) is extremely popular in computer Go which determines each action by enormous simulations in a broad and deep search tree. However, human experts select most actions by pattern analysis and careful evaluation rather than brute search of millions of future nteractions. In this paper, we propose a computer Go system that follows experts way of thinking and playing. Our system consists of two parts. The first part is a novel deep alternative neural network (DANN) used to generate candidates of next move. Compared with existing deep convolutional neural network (DCNN), DANN inserts recurrent layer after each convolutional layer and stacks them in an alternative manner. We show such setting can preserve more contexts of local features and its evolutions which are beneficial for move prediction. The second part is a long-term evaluation (LTE) module used to provide a reliable evaluation of candidates rather than a single probability from move predictor. This is consistent with human experts nature of playing since they can foresee tens of steps to give an accurate estimation of candidates. In our system, for each candidate, LTE calculates a cumulative reward after several future interactions when local variations are settled. Combining criteria from the two parts, our system determines the optimal choice of next move. For more comprehensive experiments, we introduce a new professional Go dataset (PGD), consisting of 253233 professional records. Experiments on GoGoD and PGD datasets show the DANN can substantially improve performance of move prediction over pure DCNN. When combining LTE, our system outperforms most relevant approaches and open engines based on MCTS.
new_dataset
0.963541
1706.04097
Yingyu Liang
Yuanzhi Li, Yingyu Liang
Provable Alternating Gradient Descent for Non-negative Matrix Factorization with Strong Correlations
Accepted to the International Conference on Machine Learning (ICML), 2017
null
null
null
cs.LG cs.DS cs.NA stat.ML
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Non-negative matrix factorization is a basic tool for decomposing data into the feature and weight matrices under non-negativity constraints, and in practice is often solved in the alternating minimization framework. However, it is unclear whether such algorithms can recover the ground-truth feature matrix when the weights for different features are highly correlated, which is common in applications. This paper proposes a simple and natural alternating gradient descent based algorithm, and shows that with a mild initialization it provably recovers the ground-truth in the presence of strong correlations. In most interesting cases, the correlation can be in the same order as the highest possible. Our analysis also reveals its several favorable features including robustness to noise. We complement our theoretical results with empirical studies on semi-synthetic datasets, demonstrating its advantage over several popular methods in recovering the ground-truth.
[ { "version": "v1", "created": "Tue, 13 Jun 2017 14:39:59 GMT" } ]
2017-06-14T00:00:00
[ [ "Li", "Yuanzhi", "" ], [ "Liang", "Yingyu", "" ] ]
TITLE: Provable Alternating Gradient Descent for Non-negative Matrix Factorization with Strong Correlations ABSTRACT: Non-negative matrix factorization is a basic tool for decomposing data into the feature and weight matrices under non-negativity constraints, and in practice is often solved in the alternating minimization framework. However, it is unclear whether such algorithms can recover the ground-truth feature matrix when the weights for different features are highly correlated, which is common in applications. This paper proposes a simple and natural alternating gradient descent based algorithm, and shows that with a mild initialization it provably recovers the ground-truth in the presence of strong correlations. In most interesting cases, the correlation can be in the same order as the highest possible. Our analysis also reveals its several favorable features including robustness to noise. We complement our theoretical results with empirical studies on semi-synthetic datasets, demonstrating its advantage over several popular methods in recovering the ground-truth.
no_new_dataset
0.9462
1706.04109
Fran Casino
Fran Casino, Constantinos Patsakis, Antoni Martinez-Balleste, Frederic Borras, Edgar Batista
Technical Report: Implementation and Validation of a Smart Health Application
4-page Tech Report
null
null
null
cs.AI cs.CY
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
In this article, we explain in detail the internal structures and databases of a smart health application. Moreover, we describe how to generate a statistically sound synthetic dataset using real-world medical data.
[ { "version": "v1", "created": "Tue, 13 Jun 2017 14:58:41 GMT" } ]
2017-06-14T00:00:00
[ [ "Casino", "Fran", "" ], [ "Patsakis", "Constantinos", "" ], [ "Martinez-Balleste", "Antoni", "" ], [ "Borras", "Frederic", "" ], [ "Batista", "Edgar", "" ] ]
TITLE: Technical Report: Implementation and Validation of a Smart Health Application ABSTRACT: In this article, we explain in detail the internal structures and databases of a smart health application. Moreover, we describe how to generate a statistically sound synthetic dataset using real-world medical data.
no_new_dataset
0.9255
1706.04122
Iman Abbasnejad
Iman Abbasnejad, Sridha Sridharan, Simon Denman, Clinton Fookes, Simon Lucey
Joint Max Margin and Semantic Features for Continuous Event Detection in Complex Scenes
submit to journal of Computer Vision and Image Understanding
null
null
null
cs.CV
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
In this paper the problem of complex event detection in the continuous domain (i.e. events with unknown starting and ending locations) is addressed. Existing event detection methods are limited to features that are extracted from the local spatial or spatio-temporal patches from the videos. However, this makes the model vulnerable to the events with similar concepts e.g. "Open drawer" and "Open cupboard". In this work, in order to address the aforementioned limitations we present a novel model based on the combination of semantic and temporal features extracted from video frames. We train a max-margin classifier on top of the extracted features in an adaptive framework that is able to detect the events with unknown starting and ending locations. Our model is based on the Bidirectional Region Neural Network and large margin Structural Output SVM. The generality of our model allows it to be simply applied to different labeled and unlabeled datasets. We finally test our algorithm on three challenging datasets, "UCF 101-Action Recognition", "MPII Cooking Activities" and "Hollywood", and we report state-of-the-art performance.
[ { "version": "v1", "created": "Tue, 13 Jun 2017 15:30:16 GMT" } ]
2017-06-14T00:00:00
[ [ "Abbasnejad", "Iman", "" ], [ "Sridharan", "Sridha", "" ], [ "Denman", "Simon", "" ], [ "Fookes", "Clinton", "" ], [ "Lucey", "Simon", "" ] ]
TITLE: Joint Max Margin and Semantic Features for Continuous Event Detection in Complex Scenes ABSTRACT: In this paper the problem of complex event detection in the continuous domain (i.e. events with unknown starting and ending locations) is addressed. Existing event detection methods are limited to features that are extracted from the local spatial or spatio-temporal patches from the videos. However, this makes the model vulnerable to the events with similar concepts e.g. "Open drawer" and "Open cupboard". In this work, in order to address the aforementioned limitations we present a novel model based on the combination of semantic and temporal features extracted from video frames. We train a max-margin classifier on top of the extracted features in an adaptive framework that is able to detect the events with unknown starting and ending locations. Our model is based on the Bidirectional Region Neural Network and large margin Structural Output SVM. The generality of our model allows it to be simply applied to different labeled and unlabeled datasets. We finally test our algorithm on three challenging datasets, "UCF 101-Action Recognition", "MPII Cooking Activities" and "Hollywood", and we report state-of-the-art performance.
no_new_dataset
0.949623
1603.04908
Gedas Bertasius
Gedas Bertasius, Hyun Soo Park, Stella X. Yu, and Jianbo Shi
First Person Action-Object Detection with EgoNet
null
null
null
null
cs.CV
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Unlike traditional third-person cameras mounted on robots, a first-person camera, captures a person's visual sensorimotor object interactions from up close. In this paper, we study the tight interplay between our momentary visual attention and motor action with objects from a first-person camera. We propose a concept of action-objects---the objects that capture person's conscious visual (watching a TV) or tactile (taking a cup) interactions. Action-objects may be task-dependent but since many tasks share common person-object spatial configurations, action-objects exhibit a characteristic 3D spatial distance and orientation with respect to the person. We design a predictive model that detects action-objects using EgoNet, a joint two-stream network that holistically integrates visual appearance (RGB) and 3D spatial layout (depth and height) cues to predict per-pixel likelihood of action-objects. Our network also incorporates a first-person coordinate embedding, which is designed to learn a spatial distribution of the action-objects in the first-person data. We demonstrate EgoNet's predictive power, by showing that it consistently outperforms previous baseline approaches. Furthermore, EgoNet also exhibits a strong generalization ability, i.e., it predicts semantically meaningful objects in novel first-person datasets. Our method's ability to effectively detect action-objects could be used to improve robots' understanding of human-object interactions.
[ { "version": "v1", "created": "Tue, 15 Mar 2016 22:29:03 GMT" }, { "version": "v2", "created": "Wed, 16 Nov 2016 16:59:28 GMT" }, { "version": "v3", "created": "Sat, 10 Jun 2017 18:04:17 GMT" } ]
2017-06-13T00:00:00
[ [ "Bertasius", "Gedas", "" ], [ "Park", "Hyun Soo", "" ], [ "Yu", "Stella X.", "" ], [ "Shi", "Jianbo", "" ] ]
TITLE: First Person Action-Object Detection with EgoNet ABSTRACT: Unlike traditional third-person cameras mounted on robots, a first-person camera, captures a person's visual sensorimotor object interactions from up close. In this paper, we study the tight interplay between our momentary visual attention and motor action with objects from a first-person camera. We propose a concept of action-objects---the objects that capture person's conscious visual (watching a TV) or tactile (taking a cup) interactions. Action-objects may be task-dependent but since many tasks share common person-object spatial configurations, action-objects exhibit a characteristic 3D spatial distance and orientation with respect to the person. We design a predictive model that detects action-objects using EgoNet, a joint two-stream network that holistically integrates visual appearance (RGB) and 3D spatial layout (depth and height) cues to predict per-pixel likelihood of action-objects. Our network also incorporates a first-person coordinate embedding, which is designed to learn a spatial distribution of the action-objects in the first-person data. We demonstrate EgoNet's predictive power, by showing that it consistently outperforms previous baseline approaches. Furthermore, EgoNet also exhibits a strong generalization ability, i.e., it predicts semantically meaningful objects in novel first-person datasets. Our method's ability to effectively detect action-objects could be used to improve robots' understanding of human-object interactions.
new_dataset
0.644784
1610.01675
Michael Lash
Michael T. Lash, Qihang Lin, W. Nick Street, Jennifer G. Robinson, Jeffrey Ohlmann
Generalized Inverse Classification
Accepted to SDM 2017. Full paper + supplemental material
null
10.1137/1.9781611974973.19
null
cs.LG stat.ML
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Inverse classification is the process of perturbing an instance in a meaningful way such that it is more likely to conform to a specific class. Historical methods that address such a problem are often framed to leverage only a single classifier, or specific set of classifiers. These works are often accompanied by naive assumptions. In this work we propose generalized inverse classification (GIC), which avoids restricting the classification model that can be used. We incorporate this formulation into a refined framework in which GIC takes place. Under this framework, GIC operates on features that are immediately actionable. Each change incurs an individual cost, either linear or non-linear. Such changes are subjected to occur within a specified level of cumulative change (budget). Furthermore, our framework incorporates the estimation of features that change as a consequence of direct actions taken (indirectly changeable features). To solve such a problem, we propose three real-valued heuristic-based methods and two sensitivity analysis-based comparison methods, each of which is evaluated on two freely available real-world datasets. Our results demonstrate the validity and benefits of our formulation, framework, and methods.
[ { "version": "v1", "created": "Wed, 5 Oct 2016 22:28:01 GMT" }, { "version": "v2", "created": "Thu, 12 Jan 2017 17:38:58 GMT" } ]
2017-06-13T00:00:00
[ [ "Lash", "Michael T.", "" ], [ "Lin", "Qihang", "" ], [ "Street", "W. Nick", "" ], [ "Robinson", "Jennifer G.", "" ], [ "Ohlmann", "Jeffrey", "" ] ]
TITLE: Generalized Inverse Classification ABSTRACT: Inverse classification is the process of perturbing an instance in a meaningful way such that it is more likely to conform to a specific class. Historical methods that address such a problem are often framed to leverage only a single classifier, or specific set of classifiers. These works are often accompanied by naive assumptions. In this work we propose generalized inverse classification (GIC), which avoids restricting the classification model that can be used. We incorporate this formulation into a refined framework in which GIC takes place. Under this framework, GIC operates on features that are immediately actionable. Each change incurs an individual cost, either linear or non-linear. Such changes are subjected to occur within a specified level of cumulative change (budget). Furthermore, our framework incorporates the estimation of features that change as a consequence of direct actions taken (indirectly changeable features). To solve such a problem, we propose three real-valued heuristic-based methods and two sensitivity analysis-based comparison methods, each of which is evaluated on two freely available real-world datasets. Our results demonstrate the validity and benefits of our formulation, framework, and methods.
no_new_dataset
0.9462
1611.02315
Jacob Steinhardt
Moses Charikar and Jacob Steinhardt and Gregory Valiant
Learning from Untrusted Data
Updated based on STOC camera-ready
null
null
null
cs.LG cs.AI cs.CC cs.CR math.ST stat.TH
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The vast majority of theoretical results in machine learning and statistics assume that the available training data is a reasonably reliable reflection of the phenomena to be learned or estimated. Similarly, the majority of machine learning and statistical techniques used in practice are brittle to the presence of large amounts of biased or malicious data. In this work we consider two frameworks in which to study estimation, learning, and optimization in the presence of significant fractions of arbitrary data. The first framework, list-decodable learning, asks whether it is possible to return a list of answers, with the guarantee that at least one of them is accurate. For example, given a dataset of $n$ points for which an unknown subset of $\alpha n$ points are drawn from a distribution of interest, and no assumptions are made about the remaining $(1-\alpha)n$ points, is it possible to return a list of $\operatorname{poly}(1/\alpha)$ answers, one of which is correct? The second framework, which we term the semi-verified learning model, considers the extent to which a small dataset of trusted data (drawn from the distribution in question) can be leveraged to enable the accurate extraction of information from a much larger but untrusted dataset (of which only an $\alpha$-fraction is drawn from the distribution). We show strong positive results in both settings, and provide an algorithm for robust learning in a very general stochastic optimization setting. This general result has immediate implications for robust estimation in a number of settings, including for robustly estimating the mean of distributions with bounded second moments, robustly learning mixtures of such distributions, and robustly finding planted partitions in random graphs in which significant portions of the graph have been perturbed by an adversary.
[ { "version": "v1", "created": "Mon, 7 Nov 2016 21:43:39 GMT" }, { "version": "v2", "created": "Sun, 11 Jun 2017 17:48:31 GMT" } ]
2017-06-13T00:00:00
[ [ "Charikar", "Moses", "" ], [ "Steinhardt", "Jacob", "" ], [ "Valiant", "Gregory", "" ] ]
TITLE: Learning from Untrusted Data ABSTRACT: The vast majority of theoretical results in machine learning and statistics assume that the available training data is a reasonably reliable reflection of the phenomena to be learned or estimated. Similarly, the majority of machine learning and statistical techniques used in practice are brittle to the presence of large amounts of biased or malicious data. In this work we consider two frameworks in which to study estimation, learning, and optimization in the presence of significant fractions of arbitrary data. The first framework, list-decodable learning, asks whether it is possible to return a list of answers, with the guarantee that at least one of them is accurate. For example, given a dataset of $n$ points for which an unknown subset of $\alpha n$ points are drawn from a distribution of interest, and no assumptions are made about the remaining $(1-\alpha)n$ points, is it possible to return a list of $\operatorname{poly}(1/\alpha)$ answers, one of which is correct? The second framework, which we term the semi-verified learning model, considers the extent to which a small dataset of trusted data (drawn from the distribution in question) can be leveraged to enable the accurate extraction of information from a much larger but untrusted dataset (of which only an $\alpha$-fraction is drawn from the distribution). We show strong positive results in both settings, and provide an algorithm for robust learning in a very general stochastic optimization setting. This general result has immediate implications for robust estimation in a number of settings, including for robustly estimating the mean of distributions with bounded second moments, robustly learning mixtures of such distributions, and robustly finding planted partitions in random graphs in which significant portions of the graph have been perturbed by an adversary.
no_new_dataset
0.939692
1612.05062
Thomas Nestmeyer
Thomas Nestmeyer, Peter V. Gehler
Reflectance Adaptive Filtering Improves Intrinsic Image Estimation
CVPR 2017
null
null
null
cs.CV
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Separating an image into reflectance and shading layers poses a challenge for learning approaches because no large corpus of precise and realistic ground truth decompositions exists. The Intrinsic Images in the Wild~(IIW) dataset provides a sparse set of relative human reflectance judgments, which serves as a standard benchmark for intrinsic images. A number of methods use IIW to learn statistical dependencies between the images and their reflectance layer. Although learning plays an important role for high performance, we show that a standard signal processing technique achieves performance on par with current state-of-the-art. We propose a loss function for CNN learning of dense reflectance predictions. Our results show a simple pixel-wise decision, without any context or prior knowledge, is sufficient to provide a strong baseline on IIW. This sets a competitive baseline which only two other approaches surpass. We then develop a joint bilateral filtering method that implements strong prior knowledge about reflectance constancy. This filtering operation can be applied to any intrinsic image algorithm and we improve several previous results achieving a new state-of-the-art on IIW. Our findings suggest that the effect of learning-based approaches may have been over-estimated so far. Explicit prior knowledge is still at least as important to obtain high performance in intrinsic image decompositions.
[ { "version": "v1", "created": "Thu, 15 Dec 2016 13:42:54 GMT" }, { "version": "v2", "created": "Mon, 12 Jun 2017 12:39:49 GMT" } ]
2017-06-13T00:00:00
[ [ "Nestmeyer", "Thomas", "" ], [ "Gehler", "Peter V.", "" ] ]
TITLE: Reflectance Adaptive Filtering Improves Intrinsic Image Estimation ABSTRACT: Separating an image into reflectance and shading layers poses a challenge for learning approaches because no large corpus of precise and realistic ground truth decompositions exists. The Intrinsic Images in the Wild~(IIW) dataset provides a sparse set of relative human reflectance judgments, which serves as a standard benchmark for intrinsic images. A number of methods use IIW to learn statistical dependencies between the images and their reflectance layer. Although learning plays an important role for high performance, we show that a standard signal processing technique achieves performance on par with current state-of-the-art. We propose a loss function for CNN learning of dense reflectance predictions. Our results show a simple pixel-wise decision, without any context or prior knowledge, is sufficient to provide a strong baseline on IIW. This sets a competitive baseline which only two other approaches surpass. We then develop a joint bilateral filtering method that implements strong prior knowledge about reflectance constancy. This filtering operation can be applied to any intrinsic image algorithm and we improve several previous results achieving a new state-of-the-art on IIW. Our findings suggest that the effect of learning-based approaches may have been over-estimated so far. Explicit prior knowledge is still at least as important to obtain high performance in intrinsic image decompositions.
no_new_dataset
0.944177
1612.05970
Wentao Zhu
Wentao Zhu, Xiang Xiang, Trac D. Tran, Xiaohui Xie
Adversarial Deep Structural Networks for Mammographic Mass Segmentation
First version on arXiv 2016, MICCAI 2017 Deep Learning in Medical Image Analysis (DLMIA) workshop
null
null
null
cs.CV cs.LG
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Mass segmentation is an important task in mammogram analysis, providing effective morphological features and regions of interest (ROI) for mass detection and classification. Inspired by the success of using deep convolutional features for natural image analysis and conditional random fields (CRF) for structural learning, we propose an end-to-end network for mammographic mass segmentation. The network employs a fully convolutional network (FCN) to model potential function, followed by a CRF to perform structural learning. Because the mass distribution varies greatly with pixel position, the FCN is combined with position priori for the task. Due to the small size of mammogram datasets, we use adversarial training to control over-fitting. Four models with different convolutional kernels are further fused to improve the segmentation results. Experimental results on two public datasets, INbreast and DDSM-BCRP, show that our end-to-end network combined with adversarial training achieves the-state-of-the-art results.
[ { "version": "v1", "created": "Sun, 18 Dec 2016 18:40:21 GMT" }, { "version": "v2", "created": "Fri, 9 Jun 2017 21:32:38 GMT" } ]
2017-06-13T00:00:00
[ [ "Zhu", "Wentao", "" ], [ "Xiang", "Xiang", "" ], [ "Tran", "Trac D.", "" ], [ "Xie", "Xiaohui", "" ] ]
TITLE: Adversarial Deep Structural Networks for Mammographic Mass Segmentation ABSTRACT: Mass segmentation is an important task in mammogram analysis, providing effective morphological features and regions of interest (ROI) for mass detection and classification. Inspired by the success of using deep convolutional features for natural image analysis and conditional random fields (CRF) for structural learning, we propose an end-to-end network for mammographic mass segmentation. The network employs a fully convolutional network (FCN) to model potential function, followed by a CRF to perform structural learning. Because the mass distribution varies greatly with pixel position, the FCN is combined with position priori for the task. Due to the small size of mammogram datasets, we use adversarial training to control over-fitting. Four models with different convolutional kernels are further fused to improve the segmentation results. Experimental results on two public datasets, INbreast and DDSM-BCRP, show that our end-to-end network combined with adversarial training achieves the-state-of-the-art results.
no_new_dataset
0.954563
1702.01426
Nadav Israel
Nadav Israel, Lior Wolf, Ran Barzilay, Gal Shoval
Robust features for facial action recognition
null
null
null
null
cs.CV
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Automatic recognition of facial gestures is becoming increasingly important as real world AI agents become a reality. In this paper, we present an automated system that recognizes facial gestures by capturing local changes and encoding the motion into a histogram of frequencies. We evaluate the proposed method by demonstrating its effectiveness on spontaneous face action benchmarks: the FEEDTUM dataset, the Pain dataset and the HMDB51 dataset. The results show that, compared to known methods, the new encoding methods significantly improve the recognition accuracy and the robustness of analysis for a variety of applications.
[ { "version": "v1", "created": "Sun, 5 Feb 2017 16:28:26 GMT" }, { "version": "v2", "created": "Sun, 11 Jun 2017 17:08:43 GMT" } ]
2017-06-13T00:00:00
[ [ "Israel", "Nadav", "" ], [ "Wolf", "Lior", "" ], [ "Barzilay", "Ran", "" ], [ "Shoval", "Gal", "" ] ]
TITLE: Robust features for facial action recognition ABSTRACT: Automatic recognition of facial gestures is becoming increasingly important as real world AI agents become a reality. In this paper, we present an automated system that recognizes facial gestures by capturing local changes and encoding the motion into a histogram of frequencies. We evaluate the proposed method by demonstrating its effectiveness on spontaneous face action benchmarks: the FEEDTUM dataset, the Pain dataset and the HMDB51 dataset. The results show that, compared to known methods, the new encoding methods significantly improve the recognition accuracy and the robustness of analysis for a variety of applications.
no_new_dataset
0.941061
1703.00366
Emiliano De Cristofaro
Apostolos Pyrgelis, Carmela Troncoso, Emiliano De Cristofaro
What Does The Crowd Say About You? Evaluating Aggregation-based Location Privacy
To appear in PETS 2017
null
null
null
cs.CR
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Information about people's movements and the locations they visit enables an increasing number of mobility analytics applications, e.g., in the context of urban and transportation planning, In this setting, rather than collecting or sharing raw data, entities often use aggregation as a privacy protection mechanism, aiming to hide individual users' location traces. Furthermore, to bound information leakage from the aggregates, they can perturb the input of the aggregation or its output to ensure that these are differentially private. In this paper, we set to evaluate the impact of releasing aggregate location time-series on the privacy of individuals contributing to the aggregation. We introduce a framework allowing us to reason about privacy against an adversary attempting to predict users' locations or recover their mobility patterns. We formalize these attacks as inference problems, and discuss a few strategies to model the adversary's prior knowledge based on the information she may have access to. We then use the framework to quantify the privacy loss stemming from aggregate location data, with and without the protection of differential privacy, using two real-world mobility datasets. We find that aggregates do leak information about individuals' punctual locations and mobility profiles. The density of the observations, as well as timing, play important roles, e.g., regular patterns during peak hours are better protected than sporadic movements. Finally, our evaluation shows that both output and input perturbation offer little additional protection, unless they introduce large amounts of noise ultimately destroying the utility of the data.
[ { "version": "v1", "created": "Wed, 1 Mar 2017 16:22:52 GMT" }, { "version": "v2", "created": "Tue, 6 Jun 2017 14:43:48 GMT" }, { "version": "v3", "created": "Sat, 10 Jun 2017 10:58:48 GMT" } ]
2017-06-13T00:00:00
[ [ "Pyrgelis", "Apostolos", "" ], [ "Troncoso", "Carmela", "" ], [ "De Cristofaro", "Emiliano", "" ] ]
TITLE: What Does The Crowd Say About You? Evaluating Aggregation-based Location Privacy ABSTRACT: Information about people's movements and the locations they visit enables an increasing number of mobility analytics applications, e.g., in the context of urban and transportation planning, In this setting, rather than collecting or sharing raw data, entities often use aggregation as a privacy protection mechanism, aiming to hide individual users' location traces. Furthermore, to bound information leakage from the aggregates, they can perturb the input of the aggregation or its output to ensure that these are differentially private. In this paper, we set to evaluate the impact of releasing aggregate location time-series on the privacy of individuals contributing to the aggregation. We introduce a framework allowing us to reason about privacy against an adversary attempting to predict users' locations or recover their mobility patterns. We formalize these attacks as inference problems, and discuss a few strategies to model the adversary's prior knowledge based on the information she may have access to. We then use the framework to quantify the privacy loss stemming from aggregate location data, with and without the protection of differential privacy, using two real-world mobility datasets. We find that aggregates do leak information about individuals' punctual locations and mobility profiles. The density of the observations, as well as timing, play important roles, e.g., regular patterns during peak hours are better protected than sporadic movements. Finally, our evaluation shows that both output and input perturbation offer little additional protection, unless they introduce large amounts of noise ultimately destroying the utility of the data.
no_new_dataset
0.943034
1703.01041
Esteban Real
Esteban Real, Sherry Moore, Andrew Selle, Saurabh Saxena, Yutaka Leon Suematsu, Jie Tan, Quoc Le, Alex Kurakin
Large-Scale Evolution of Image Classifiers
Accepted for publication at ICML 2017 (34th International Conference on Machine Learning)
null
null
null
cs.NE cs.AI cs.CV cs.DC
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Neural networks have proven effective at solving difficult problems but designing their architectures can be challenging, even for image classification problems alone. Our goal is to minimize human participation, so we employ evolutionary algorithms to discover such networks automatically. Despite significant computational requirements, we show that it is now possible to evolve models with accuracies within the range of those published in the last year. Specifically, we employ simple evolutionary techniques at unprecedented scales to discover models for the CIFAR-10 and CIFAR-100 datasets, starting from trivial initial conditions and reaching accuracies of 94.6% (95.6% for ensemble) and 77.0%, respectively. To do this, we use novel and intuitive mutation operators that navigate large search spaces; we stress that no human participation is required once evolution starts and that the output is a fully-trained model. Throughout this work, we place special emphasis on the repeatability of results, the variability in the outcomes and the computational requirements.
[ { "version": "v1", "created": "Fri, 3 Mar 2017 05:41:30 GMT" }, { "version": "v2", "created": "Sun, 11 Jun 2017 08:42:28 GMT" } ]
2017-06-13T00:00:00
[ [ "Real", "Esteban", "" ], [ "Moore", "Sherry", "" ], [ "Selle", "Andrew", "" ], [ "Saxena", "Saurabh", "" ], [ "Suematsu", "Yutaka Leon", "" ], [ "Tan", "Jie", "" ], [ "Le", "Quoc", "" ], [ "Kurakin", "Alex", "" ] ]
TITLE: Large-Scale Evolution of Image Classifiers ABSTRACT: Neural networks have proven effective at solving difficult problems but designing their architectures can be challenging, even for image classification problems alone. Our goal is to minimize human participation, so we employ evolutionary algorithms to discover such networks automatically. Despite significant computational requirements, we show that it is now possible to evolve models with accuracies within the range of those published in the last year. Specifically, we employ simple evolutionary techniques at unprecedented scales to discover models for the CIFAR-10 and CIFAR-100 datasets, starting from trivial initial conditions and reaching accuracies of 94.6% (95.6% for ensemble) and 77.0%, respectively. To do this, we use novel and intuitive mutation operators that navigate large search spaces; we stress that no human participation is required once evolution starts and that the output is a fully-trained model. Throughout this work, we place special emphasis on the repeatability of results, the variability in the outcomes and the computational requirements.
no_new_dataset
0.948442
1703.01958
David Hallac
David Hallac, Youngsuk Park, Stephen Boyd, Jure Leskovec
Network Inference via the Time-Varying Graphical Lasso
null
null
null
null
cs.LG cs.SI math.OC
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Many important problems can be modeled as a system of interconnected entities, where each entity is recording time-dependent observations or measurements. In order to spot trends, detect anomalies, and interpret the temporal dynamics of such data, it is essential to understand the relationships between the different entities and how these relationships evolve over time. In this paper, we introduce the time-varying graphical lasso (TVGL), a method of inferring time-varying networks from raw time series data. We cast the problem in terms of estimating a sparse time-varying inverse covariance matrix, which reveals a dynamic network of interdependencies between the entities. Since dynamic network inference is a computationally expensive task, we derive a scalable message-passing algorithm based on the Alternating Direction Method of Multipliers (ADMM) to solve this problem in an efficient way. We also discuss several extensions, including a streaming algorithm to update the model and incorporate new observations in real time. Finally, we evaluate our TVGL algorithm on both real and synthetic datasets, obtaining interpretable results and outperforming state-of-the-art baselines in terms of both accuracy and scalability.
[ { "version": "v1", "created": "Mon, 6 Mar 2017 16:35:48 GMT" }, { "version": "v2", "created": "Sat, 10 Jun 2017 01:07:39 GMT" } ]
2017-06-13T00:00:00
[ [ "Hallac", "David", "" ], [ "Park", "Youngsuk", "" ], [ "Boyd", "Stephen", "" ], [ "Leskovec", "Jure", "" ] ]
TITLE: Network Inference via the Time-Varying Graphical Lasso ABSTRACT: Many important problems can be modeled as a system of interconnected entities, where each entity is recording time-dependent observations or measurements. In order to spot trends, detect anomalies, and interpret the temporal dynamics of such data, it is essential to understand the relationships between the different entities and how these relationships evolve over time. In this paper, we introduce the time-varying graphical lasso (TVGL), a method of inferring time-varying networks from raw time series data. We cast the problem in terms of estimating a sparse time-varying inverse covariance matrix, which reveals a dynamic network of interdependencies between the entities. Since dynamic network inference is a computationally expensive task, we derive a scalable message-passing algorithm based on the Alternating Direction Method of Multipliers (ADMM) to solve this problem in an efficient way. We also discuss several extensions, including a streaming algorithm to update the model and incorporate new observations in real time. Finally, we evaluate our TVGL algorithm on both real and synthetic datasets, obtaining interpretable results and outperforming state-of-the-art baselines in terms of both accuracy and scalability.
no_new_dataset
0.946745
1704.05179
Levent Sagun
Matthew Dunn, Levent Sagun, Mike Higgins, V. Ugur Guney, Volkan Cirik and Kyunghyun Cho
SearchQA: A New Q&A Dataset Augmented with Context from a Search Engine
null
null
null
null
cs.CL
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We publicly release a new large-scale dataset, called SearchQA, for machine comprehension, or question-answering. Unlike recently released datasets, such as DeepMind CNN/DailyMail and SQuAD, the proposed SearchQA was constructed to reflect a full pipeline of general question-answering. That is, we start not from an existing article and generate a question-answer pair, but start from an existing question-answer pair, crawled from J! Archive, and augment it with text snippets retrieved by Google. Following this approach, we built SearchQA, which consists of more than 140k question-answer pairs with each pair having 49.6 snippets on average. Each question-answer-context tuple of the SearchQA comes with additional meta-data such as the snippet's URL, which we believe will be valuable resources for future research. We conduct human evaluation as well as test two baseline methods, one simple word selection and the other deep learning based, on the SearchQA. We show that there is a meaningful gap between the human and machine performances. This suggests that the proposed dataset could well serve as a benchmark for question-answering.
[ { "version": "v1", "created": "Tue, 18 Apr 2017 02:42:17 GMT" }, { "version": "v2", "created": "Thu, 4 May 2017 14:07:21 GMT" }, { "version": "v3", "created": "Sun, 11 Jun 2017 11:51:06 GMT" } ]
2017-06-13T00:00:00
[ [ "Dunn", "Matthew", "" ], [ "Sagun", "Levent", "" ], [ "Higgins", "Mike", "" ], [ "Guney", "V. Ugur", "" ], [ "Cirik", "Volkan", "" ], [ "Cho", "Kyunghyun", "" ] ]
TITLE: SearchQA: A New Q&A Dataset Augmented with Context from a Search Engine ABSTRACT: We publicly release a new large-scale dataset, called SearchQA, for machine comprehension, or question-answering. Unlike recently released datasets, such as DeepMind CNN/DailyMail and SQuAD, the proposed SearchQA was constructed to reflect a full pipeline of general question-answering. That is, we start not from an existing article and generate a question-answer pair, but start from an existing question-answer pair, crawled from J! Archive, and augment it with text snippets retrieved by Google. Following this approach, we built SearchQA, which consists of more than 140k question-answer pairs with each pair having 49.6 snippets on average. Each question-answer-context tuple of the SearchQA comes with additional meta-data such as the snippet's URL, which we believe will be valuable resources for future research. We conduct human evaluation as well as test two baseline methods, one simple word selection and the other deep learning based, on the SearchQA. We show that there is a meaningful gap between the human and machine performances. This suggests that the proposed dataset could well serve as a benchmark for question-answering.
new_dataset
0.956594
1705.01209
Gan Sun
Gan Sun, Yang Cong, Ji Liu and Xiaowei Xu
Lifelong Metric Learning
10 pages, 6 figures
null
null
null
cs.LG cs.AI
http://creativecommons.org/licenses/by/4.0/
The state-of-the-art online learning approaches are only capable of learning the metric for predefined tasks. In this paper, we consider lifelong learning problem to mimic "human learning", i.e., endowing a new capability to the learned metric for a new task from new online samples and incorporating previous experiences and knowledge. Therefore, we propose a new metric learning framework: lifelong metric learning (LML), which only utilizes the data of the new task to train the metric model while preserving the original capabilities. More specifically, the proposed LML maintains a common subspace for all learned metrics, named lifelong dictionary, transfers knowledge from the common subspace to each new metric task with task-specific idiosyncrasy, and redefines the common subspace over time to maximize performance across all metric tasks. For model optimization, we apply online passive aggressive optimization algorithm to solve the proposed LML framework, where the lifelong dictionary and task-specific partition are optimized alternatively and consecutively. Finally, we evaluate our approach by analyzing several multi-task metric learning datasets. Extensive experimental results demonstrate effectiveness and efficiency of the proposed framework.
[ { "version": "v1", "created": "Wed, 3 May 2017 00:31:55 GMT" }, { "version": "v2", "created": "Mon, 12 Jun 2017 15:09:20 GMT" } ]
2017-06-13T00:00:00
[ [ "Sun", "Gan", "" ], [ "Cong", "Yang", "" ], [ "Liu", "Ji", "" ], [ "Xu", "Xiaowei", "" ] ]
TITLE: Lifelong Metric Learning ABSTRACT: The state-of-the-art online learning approaches are only capable of learning the metric for predefined tasks. In this paper, we consider lifelong learning problem to mimic "human learning", i.e., endowing a new capability to the learned metric for a new task from new online samples and incorporating previous experiences and knowledge. Therefore, we propose a new metric learning framework: lifelong metric learning (LML), which only utilizes the data of the new task to train the metric model while preserving the original capabilities. More specifically, the proposed LML maintains a common subspace for all learned metrics, named lifelong dictionary, transfers knowledge from the common subspace to each new metric task with task-specific idiosyncrasy, and redefines the common subspace over time to maximize performance across all metric tasks. For model optimization, we apply online passive aggressive optimization algorithm to solve the proposed LML framework, where the lifelong dictionary and task-specific partition are optimized alternatively and consecutively. Finally, we evaluate our approach by analyzing several multi-task metric learning datasets. Extensive experimental results demonstrate effectiveness and efficiency of the proposed framework.
no_new_dataset
0.95018
1706.03112
Rameswar Panda
Rameswar Panda, Amran Bhuiyan, Vittorio Murino, Amit K. Roy-Chowdhury
Unsupervised Adaptive Re-identification in Open World Dynamic Camera Networks
CVPR 2017 Spotlight
null
null
null
cs.CV
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Person re-identification is an open and challenging problem in computer vision. Existing approaches have concentrated on either designing the best feature representation or learning optimal matching metrics in a static setting where the number of cameras are fixed in a network. Most approaches have neglected the dynamic and open world nature of the re-identification problem, where a new camera may be temporarily inserted into an existing system to get additional information. To address such a novel and very practical problem, we propose an unsupervised adaptation scheme for re-identification models in a dynamic camera network. First, we formulate a domain perceptive re-identification method based on geodesic flow kernel that can effectively find the best source camera (already installed) to adapt with a newly introduced target camera, without requiring a very expensive training phase. Second, we introduce a transitive inference algorithm for re-identification that can exploit the information from best source camera to improve the accuracy across other camera pairs in a network of multiple cameras. Extensive experiments on four benchmark datasets demonstrate that the proposed approach significantly outperforms the state-of-the-art unsupervised learning based alternatives whilst being extremely efficient to compute.
[ { "version": "v1", "created": "Fri, 9 Jun 2017 20:17:55 GMT" } ]
2017-06-13T00:00:00
[ [ "Panda", "Rameswar", "" ], [ "Bhuiyan", "Amran", "" ], [ "Murino", "Vittorio", "" ], [ "Roy-Chowdhury", "Amit K.", "" ] ]
TITLE: Unsupervised Adaptive Re-identification in Open World Dynamic Camera Networks ABSTRACT: Person re-identification is an open and challenging problem in computer vision. Existing approaches have concentrated on either designing the best feature representation or learning optimal matching metrics in a static setting where the number of cameras are fixed in a network. Most approaches have neglected the dynamic and open world nature of the re-identification problem, where a new camera may be temporarily inserted into an existing system to get additional information. To address such a novel and very practical problem, we propose an unsupervised adaptation scheme for re-identification models in a dynamic camera network. First, we formulate a domain perceptive re-identification method based on geodesic flow kernel that can effectively find the best source camera (already installed) to adapt with a newly introduced target camera, without requiring a very expensive training phase. Second, we introduce a transitive inference algorithm for re-identification that can exploit the information from best source camera to improve the accuracy across other camera pairs in a network of multiple cameras. Extensive experiments on four benchmark datasets demonstrate that the proposed approach significantly outperforms the state-of-the-art unsupervised learning based alternatives whilst being extremely efficient to compute.
no_new_dataset
0.948917
1706.03114
Rameswar Panda
Rameswar Panda, Amit K. Roy-Chowdhury
Collaborative Summarization of Topic-Related Videos
CVPR 2017
null
null
null
cs.CV
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Large collections of videos are grouped into clusters by a topic keyword, such as Eiffel Tower or Surfing, with many important visual concepts repeating across them. Such a topically close set of videos have mutual influence on each other, which could be used to summarize one of them by exploiting information from others in the set. We build on this intuition to develop a novel approach to extract a summary that simultaneously captures both important particularities arising in the given video, as well as, generalities identified from the set of videos. The topic-related videos provide visual context to identify the important parts of the video being summarized. We achieve this by developing a collaborative sparse optimization method which can be efficiently solved by a half-quadratic minimization algorithm. Our work builds upon the idea of collaborative techniques from information retrieval and natural language processing, which typically use the attributes of other similar objects to predict the attribute of a given object. Experiments on two challenging and diverse datasets well demonstrate the efficacy of our approach over state-of-the-art methods.
[ { "version": "v1", "created": "Fri, 9 Jun 2017 20:23:43 GMT" } ]
2017-06-13T00:00:00
[ [ "Panda", "Rameswar", "" ], [ "Roy-Chowdhury", "Amit K.", "" ] ]
TITLE: Collaborative Summarization of Topic-Related Videos ABSTRACT: Large collections of videos are grouped into clusters by a topic keyword, such as Eiffel Tower or Surfing, with many important visual concepts repeating across them. Such a topically close set of videos have mutual influence on each other, which could be used to summarize one of them by exploiting information from others in the set. We build on this intuition to develop a novel approach to extract a summary that simultaneously captures both important particularities arising in the given video, as well as, generalities identified from the set of videos. The topic-related videos provide visual context to identify the important parts of the video being summarized. We achieve this by developing a collaborative sparse optimization method which can be efficiently solved by a half-quadratic minimization algorithm. Our work builds upon the idea of collaborative techniques from information retrieval and natural language processing, which typically use the attributes of other similar objects to predict the attribute of a given object. Experiments on two challenging and diverse datasets well demonstrate the efficacy of our approach over state-of-the-art methods.
no_new_dataset
0.948202
1706.03121
Rameswar Panda
Rameswar Panda, Amit K. Roy-Chowdhury
Multi-View Surveillance Video Summarization via Joint Embedding and Sparse Optimization
IEEE Trans. on Multimedia, 2017 (In Press)
null
null
null
cs.CV
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Most traditional video summarization methods are designed to generate effective summaries for single-view videos, and thus they cannot fully exploit the complicated intra and inter-view correlations in summarizing multi-view videos in a camera network. In this paper, with the aim of summarizing multi-view videos, we introduce a novel unsupervised framework via joint embedding and sparse representative selection. The objective function is two-fold. The first is to capture the multi-view correlations via an embedding, which helps in extracting a diverse set of representatives. The second is to use a `2;1- norm to model the sparsity while selecting representative shots for the summary. We propose to jointly optimize both of the objectives, such that embedding can not only characterize the correlations, but also indicate the requirements of sparse representative selection. We present an efficient alternating algorithm based on half-quadratic minimization to solve the proposed non-smooth and non-convex objective with convergence analysis. A key advantage of the proposed approach with respect to the state-of-the-art is that it can summarize multi-view videos without assuming any prior correspondences/alignment between them, e.g., uncalibrated camera networks. Rigorous experiments on several multi-view datasets demonstrate that our approach clearly outperforms the state-of-the-art methods.
[ { "version": "v1", "created": "Fri, 9 Jun 2017 20:56:20 GMT" } ]
2017-06-13T00:00:00
[ [ "Panda", "Rameswar", "" ], [ "Roy-Chowdhury", "Amit K.", "" ] ]
TITLE: Multi-View Surveillance Video Summarization via Joint Embedding and Sparse Optimization ABSTRACT: Most traditional video summarization methods are designed to generate effective summaries for single-view videos, and thus they cannot fully exploit the complicated intra and inter-view correlations in summarizing multi-view videos in a camera network. In this paper, with the aim of summarizing multi-view videos, we introduce a novel unsupervised framework via joint embedding and sparse representative selection. The objective function is two-fold. The first is to capture the multi-view correlations via an embedding, which helps in extracting a diverse set of representatives. The second is to use a `2;1- norm to model the sparsity while selecting representative shots for the summary. We propose to jointly optimize both of the objectives, such that embedding can not only characterize the correlations, but also indicate the requirements of sparse representative selection. We present an efficient alternating algorithm based on half-quadratic minimization to solve the proposed non-smooth and non-convex objective with convergence analysis. A key advantage of the proposed approach with respect to the state-of-the-art is that it can summarize multi-view videos without assuming any prior correspondences/alignment between them, e.g., uncalibrated camera networks. Rigorous experiments on several multi-view datasets demonstrate that our approach clearly outperforms the state-of-the-art methods.
no_new_dataset
0.944689
1706.03205
Xiang Wang
Xiang Wang, Xiangnan He, Liqiang Nie, Tat-Seng Chua
Item Silk Road: Recommending Items from Information Domains to Social Users
10 pages, 7 figures, SIGIR 2017
null
10.1145/3077136.3080771
null
cs.IR cs.AI cs.SI
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Online platforms can be divided into information-oriented and social-oriented domains. The former refers to forums or E-commerce sites that emphasize user-item interactions, like Trip.com and Amazon; whereas the latter refers to social networking services (SNSs) that have rich user-user connections, such as Facebook and Twitter. Despite their heterogeneity, these two domains can be bridged by a few overlapping users, dubbed as bridge users. In this work, we address the problem of cross-domain social recommendation, i.e., recommending relevant items of information domains to potential users of social networks. To our knowledge, this is a new problem that has rarely been studied before. Existing cross-domain recommender systems are unsuitable for this task since they have either focused on homogeneous information domains or assumed that users are fully overlapped. Towards this end, we present a novel Neural Social Collaborative Ranking (NSCR) approach, which seamlessly sews up the user-item interactions in information domains and user-user connections in SNSs. In the information domain part, the attributes of users and items are leveraged to strengthen the embedding learning of users and items. In the SNS part, the embeddings of bridge users are propagated to learn the embeddings of other non-bridge users. Extensive experiments on two real-world datasets demonstrate the effectiveness and rationality of our NSCR method.
[ { "version": "v1", "created": "Sat, 10 Jun 2017 08:58:02 GMT" } ]
2017-06-13T00:00:00
[ [ "Wang", "Xiang", "" ], [ "He", "Xiangnan", "" ], [ "Nie", "Liqiang", "" ], [ "Chua", "Tat-Seng", "" ] ]
TITLE: Item Silk Road: Recommending Items from Information Domains to Social Users ABSTRACT: Online platforms can be divided into information-oriented and social-oriented domains. The former refers to forums or E-commerce sites that emphasize user-item interactions, like Trip.com and Amazon; whereas the latter refers to social networking services (SNSs) that have rich user-user connections, such as Facebook and Twitter. Despite their heterogeneity, these two domains can be bridged by a few overlapping users, dubbed as bridge users. In this work, we address the problem of cross-domain social recommendation, i.e., recommending relevant items of information domains to potential users of social networks. To our knowledge, this is a new problem that has rarely been studied before. Existing cross-domain recommender systems are unsuitable for this task since they have either focused on homogeneous information domains or assumed that users are fully overlapped. Towards this end, we present a novel Neural Social Collaborative Ranking (NSCR) approach, which seamlessly sews up the user-item interactions in information domains and user-user connections in SNSs. In the information domain part, the attributes of users and items are leveraged to strengthen the embedding learning of users and items. In the SNS part, the embeddings of bridge users are propagated to learn the embeddings of other non-bridge users. Extensive experiments on two real-world datasets demonstrate the effectiveness and rationality of our NSCR method.
no_new_dataset
0.94801
1706.03206
Veronica Estrada-Galinanes
Veronica del Carmen Estrada
Analysis of Anomalies in the Internet Traffic Observed at the Campus Network Gateway
Master Thesis, January 14th 2011, Graduate School of Interdisciplinary Information Studies, University of Tokyo
null
null
10m096404-01
cs.CR
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
A considerable portion of the machine learning literature applied to intrusion detection uses outdated data sets based on a simulated network with a limited environment. Moreover, flaws usually appear in datasets and the way we handle them may impact on measurements. Finally, the detection capacity of intrusion detection is highly influenced by the system configuration. We focus on a topic rarely investigated: the characterization of anomalies in a large network environment. Intrusion Detection System (IDS) are used to detect exploits or other attacks that raise alarms. These anomalous events usually receive less attention than attack alarms, causing them to be frequently overlooked by security administrators. However, the observation of this activity contributes to understand the traffic network characteristics. On one hand, abnormal behaviors may be legitimate, e.g., misinterpreted protocols or malfunctioning network equipment, but on the other hand an attacker may intentionally craft packets to introduce anomalies to evade monitoring systems. Anomalies found in operational network environments may indicate cases of evasion attacks, application bugs, and a wide variety of factors that highly influence intrusion detection performance. This study explores the nature of anomalies found in U-Tokyo Network using cooperatively Bro and Snort IDS among other resources. We analyze 6.5 TB of compressed binary tcpdump data representing 12 hours of network traffic. Our major contributions can be summarized in: 1) reporting the anomalies observed in real, up-to-date traffic from a large academic network environment, and documenting problems in research that may lead to wrong results due to misinterpretations of data or misconfigurations in software; 2) assessing the quality of data by analyzing the potential and the real problems in the capture process.
[ { "version": "v1", "created": "Sat, 10 Jun 2017 09:00:51 GMT" } ]
2017-06-13T00:00:00
[ [ "Estrada", "Veronica del Carmen", "" ] ]
TITLE: Analysis of Anomalies in the Internet Traffic Observed at the Campus Network Gateway ABSTRACT: A considerable portion of the machine learning literature applied to intrusion detection uses outdated data sets based on a simulated network with a limited environment. Moreover, flaws usually appear in datasets and the way we handle them may impact on measurements. Finally, the detection capacity of intrusion detection is highly influenced by the system configuration. We focus on a topic rarely investigated: the characterization of anomalies in a large network environment. Intrusion Detection System (IDS) are used to detect exploits or other attacks that raise alarms. These anomalous events usually receive less attention than attack alarms, causing them to be frequently overlooked by security administrators. However, the observation of this activity contributes to understand the traffic network characteristics. On one hand, abnormal behaviors may be legitimate, e.g., misinterpreted protocols or malfunctioning network equipment, but on the other hand an attacker may intentionally craft packets to introduce anomalies to evade monitoring systems. Anomalies found in operational network environments may indicate cases of evasion attacks, application bugs, and a wide variety of factors that highly influence intrusion detection performance. This study explores the nature of anomalies found in U-Tokyo Network using cooperatively Bro and Snort IDS among other resources. We analyze 6.5 TB of compressed binary tcpdump data representing 12 hours of network traffic. Our major contributions can be summarized in: 1) reporting the anomalies observed in real, up-to-date traffic from a large academic network environment, and documenting problems in research that may lead to wrong results due to misinterpretations of data or misconfigurations in software; 2) assessing the quality of data by analyzing the potential and the real problems in the capture process.
no_new_dataset
0.938576
1706.03249
Rishabh Mehrotra
Rishabh Mehrotra and Prasanta Bhattacharya
Characterizing and Predicting Supply-side Engagement on Crowd-contributed Video Sharing Platforms
8 pages, ICTIR 2017
null
null
null
cs.HC cs.IR cs.MM
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Video sharing and entertainment websites have rapidly grown in popularity and now constitute some of the most visited websites on the Internet. Despite the active user engagement on these online video-sharing platforms, most of recent research on online media platforms have restricted themselves to networking based social media sites, like Facebook or Twitter. We depart from previous studies in the online media space that have focused exclusively on demand-side user engagement, by modeling the supply-side of the crowd-contributed videos on this platform. The current study is among the first to perform a large-scale empirical study using longitudinal video upload data from a large online video platform. The modeling and subsequent prediction of video uploads is made complicated by the heterogeneity of video types (e.g. popular vs. niche video genres), and the inherent time trend effects associated with media uploads. We identify distinct genre-clusters from our dataset and employ a self-exciting Hawkes point-process model on each of these clusters to fully specify and estimate the video upload process. Additionally, we go beyond prediction to disentangle potential factors that govern user engagement and determine the video upload rates, which improves our analysis with additional explanatory power. Our findings show that using a relatively parsimonious point-process model, we are able to achieve higher model fit, and predict video uploads to the platform with a higher accuracy than competing models. The findings from this study can benefit platform owners in better understanding how their supply-side users engage with their site over time. We also offer a robust method for performing media upload prediction that is likely to be generalizable across media platforms which demonstrate similar temporal and genre-level heterogeneity.
[ { "version": "v1", "created": "Sat, 10 Jun 2017 16:26:48 GMT" } ]
2017-06-13T00:00:00
[ [ "Mehrotra", "Rishabh", "" ], [ "Bhattacharya", "Prasanta", "" ] ]
TITLE: Characterizing and Predicting Supply-side Engagement on Crowd-contributed Video Sharing Platforms ABSTRACT: Video sharing and entertainment websites have rapidly grown in popularity and now constitute some of the most visited websites on the Internet. Despite the active user engagement on these online video-sharing platforms, most of recent research on online media platforms have restricted themselves to networking based social media sites, like Facebook or Twitter. We depart from previous studies in the online media space that have focused exclusively on demand-side user engagement, by modeling the supply-side of the crowd-contributed videos on this platform. The current study is among the first to perform a large-scale empirical study using longitudinal video upload data from a large online video platform. The modeling and subsequent prediction of video uploads is made complicated by the heterogeneity of video types (e.g. popular vs. niche video genres), and the inherent time trend effects associated with media uploads. We identify distinct genre-clusters from our dataset and employ a self-exciting Hawkes point-process model on each of these clusters to fully specify and estimate the video upload process. Additionally, we go beyond prediction to disentangle potential factors that govern user engagement and determine the video upload rates, which improves our analysis with additional explanatory power. Our findings show that using a relatively parsimonious point-process model, we are able to achieve higher model fit, and predict video uploads to the platform with a higher accuracy than competing models. The findings from this study can benefit platform owners in better understanding how their supply-side users engage with their site over time. We also offer a robust method for performing media upload prediction that is likely to be generalizable across media platforms which demonstrate similar temporal and genre-level heterogeneity.
no_new_dataset
0.943138
1706.03256
Soheil Khorram
John Gideon, Soheil Khorram, Zakaria Aldeneh, Dimitrios Dimitriadis, Emily Mower Provost
Progressive Neural Networks for Transfer Learning in Emotion Recognition
5 pages, 4 figures, to appear in the proceedings of Interspeech 2017
null
null
null
cs.LG
http://creativecommons.org/licenses/by/4.0/
Many paralinguistic tasks are closely related and thus representations learned in one domain can be leveraged for another. In this paper, we investigate how knowledge can be transferred between three paralinguistic tasks: speaker, emotion, and gender recognition. Further, we extend this problem to cross-dataset tasks, asking how knowledge captured in one emotion dataset can be transferred to another. We focus on progressive neural networks and compare these networks to the conventional deep learning method of pre-training and fine-tuning. Progressive neural networks provide a way to transfer knowledge and avoid the forgetting effect present when pre-training neural networks on different tasks. Our experiments demonstrate that: (1) emotion recognition can benefit from using representations originally learned for different paralinguistic tasks and (2) transfer learning can effectively leverage additional datasets to improve the performance of emotion recognition systems.
[ { "version": "v1", "created": "Sat, 10 Jun 2017 17:26:20 GMT" } ]
2017-06-13T00:00:00
[ [ "Gideon", "John", "" ], [ "Khorram", "Soheil", "" ], [ "Aldeneh", "Zakaria", "" ], [ "Dimitriadis", "Dimitrios", "" ], [ "Provost", "Emily Mower", "" ] ]
TITLE: Progressive Neural Networks for Transfer Learning in Emotion Recognition ABSTRACT: Many paralinguistic tasks are closely related and thus representations learned in one domain can be leveraged for another. In this paper, we investigate how knowledge can be transferred between three paralinguistic tasks: speaker, emotion, and gender recognition. Further, we extend this problem to cross-dataset tasks, asking how knowledge captured in one emotion dataset can be transferred to another. We focus on progressive neural networks and compare these networks to the conventional deep learning method of pre-training and fine-tuning. Progressive neural networks provide a way to transfer knowledge and avoid the forgetting effect present when pre-training neural networks on different tasks. Our experiments demonstrate that: (1) emotion recognition can benefit from using representations originally learned for different paralinguistic tasks and (2) transfer learning can effectively leverage additional datasets to improve the performance of emotion recognition systems.
no_new_dataset
0.948822
1706.03367
Carlos G\'omez-Rodr\'iguez
Daniel Fern\'andez-Gonz\'alez, Carlos G\'omez-Rodr\'iguez
A Full Non-Monotonic Transition System for Unrestricted Non-Projective Parsing
11 pages. Accepted for publication at ACL 2017
null
null
null
cs.CL
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Restricted non-monotonicity has been shown beneficial for the projective arc-eager dependency parser in previous research, as posterior decisions can repair mistakes made in previous states due to the lack of information. In this paper, we propose a novel, fully non-monotonic transition system based on the non-projective Covington algorithm. As a non-monotonic system requires exploration of erroneous actions during the training process, we develop several non-monotonic variants of the recently defined dynamic oracle for the Covington parser, based on tight approximations of the loss. Experiments on datasets from the CoNLL-X and CoNLL-XI shared tasks show that a non-monotonic dynamic oracle outperforms the monotonic version in the majority of languages.
[ { "version": "v1", "created": "Sun, 11 Jun 2017 16:04:42 GMT" } ]
2017-06-13T00:00:00
[ [ "Fernández-González", "Daniel", "" ], [ "Gómez-Rodríguez", "Carlos", "" ] ]
TITLE: A Full Non-Monotonic Transition System for Unrestricted Non-Projective Parsing ABSTRACT: Restricted non-monotonicity has been shown beneficial for the projective arc-eager dependency parser in previous research, as posterior decisions can repair mistakes made in previous states due to the lack of information. In this paper, we propose a novel, fully non-monotonic transition system based on the non-projective Covington algorithm. As a non-monotonic system requires exploration of erroneous actions during the training process, we develop several non-monotonic variants of the recently defined dynamic oracle for the Covington parser, based on tight approximations of the loss. Experiments on datasets from the CoNLL-X and CoNLL-XI shared tasks show that a non-monotonic dynamic oracle outperforms the monotonic version in the majority of languages.
no_new_dataset
0.946597
1706.03412
Evgeny Burnaev
Vladislav Ishimtsev, Ivan Nazarov, Alexander Bernstein and Evgeny Burnaev
Conformal k-NN Anomaly Detector for Univariate Data Streams
15 pages, 2 figures, 7 tables
null
null
null
stat.ML cs.DS stat.AP stat.CO stat.ME
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Anomalies in time-series data give essential and often actionable information in many applications. In this paper we consider a model-free anomaly detection method for univariate time-series which adapts to non-stationarity in the data stream and provides probabilistic abnormality scores based on the conformal prediction paradigm. Despite its simplicity the method performs on par with complex prediction-based models on the Numenta Anomaly Detection benchmark and the Yahoo! S5 dataset.
[ { "version": "v1", "created": "Sun, 11 Jun 2017 21:45:24 GMT" } ]
2017-06-13T00:00:00
[ [ "Ishimtsev", "Vladislav", "" ], [ "Nazarov", "Ivan", "" ], [ "Bernstein", "Alexander", "" ], [ "Burnaev", "Evgeny", "" ] ]
TITLE: Conformal k-NN Anomaly Detector for Univariate Data Streams ABSTRACT: Anomalies in time-series data give essential and often actionable information in many applications. In this paper we consider a model-free anomaly detection method for univariate time-series which adapts to non-stationarity in the data stream and provides probabilistic abnormality scores based on the conformal prediction paradigm. Despite its simplicity the method performs on par with complex prediction-based models on the Numenta Anomaly Detection benchmark and the Yahoo! S5 dataset.
no_new_dataset
0.953319
1706.03449
Arman Cohan
Arman Cohan, Nazli Goharian
Scientific document summarization via citation contextualization and scientific discourse
Preprint. The final publication is available at Springer via http://dx.doi.org/10.1007/s00799-017-0216-8, International Journal on Digital Libraries (IJDL) 2017
null
10.1007/s00799-017-0216-8
null
cs.CL cs.DL
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The rapid growth of scientific literature has made it difficult for the researchers to quickly learn about the developments in their respective fields. Scientific document summarization addresses this challenge by providing summaries of the important contributions of scientific papers. We present a framework for scientific summarization which takes advantage of the citations and the scientific discourse structure. Citation texts often lack the evidence and context to support the content of the cited paper and are even sometimes inaccurate. We first address the problem of inaccuracy of the citation texts by finding the relevant context from the cited paper. We propose three approaches for contextualizing citations which are based on query reformulation, word embeddings, and supervised learning. We then train a model to identify the discourse facets for each citation. We finally propose a method for summarizing scientific papers by leveraging the faceted citations and their corresponding contexts. We evaluate our proposed method on two scientific summarization datasets in the biomedical and computational linguistics domains. Extensive evaluation results show that our methods can improve over the state of the art by large margins.
[ { "version": "v1", "created": "Mon, 12 Jun 2017 03:21:38 GMT" } ]
2017-06-13T00:00:00
[ [ "Cohan", "Arman", "" ], [ "Goharian", "Nazli", "" ] ]
TITLE: Scientific document summarization via citation contextualization and scientific discourse ABSTRACT: The rapid growth of scientific literature has made it difficult for the researchers to quickly learn about the developments in their respective fields. Scientific document summarization addresses this challenge by providing summaries of the important contributions of scientific papers. We present a framework for scientific summarization which takes advantage of the citations and the scientific discourse structure. Citation texts often lack the evidence and context to support the content of the cited paper and are even sometimes inaccurate. We first address the problem of inaccuracy of the citation texts by finding the relevant context from the cited paper. We propose three approaches for contextualizing citations which are based on query reformulation, word embeddings, and supervised learning. We then train a model to identify the discourse facets for each citation. We finally propose a method for summarizing scientific papers by leveraging the faceted citations and their corresponding contexts. We evaluate our proposed method on two scientific summarization datasets in the biomedical and computational linguistics domains. Extensive evaluation results show that our methods can improve over the state of the art by large margins.
no_new_dataset
0.946695
1706.03509
Veronika Cheplygina
Veronika Cheplygina and Pim Moeskops and Mitko Veta and Behdad Dasht Bozorg and Josien Pluim
Exploring the similarity of medical imaging classification problems
null
null
null
null
cs.CV
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Supervised learning is ubiquitous in medical image analysis. In this paper we consider the problem of meta-learning -- predicting which methods will perform well in an unseen classification problem, given previous experience with other classification problems. We investigate the first step of such an approach: how to quantify the similarity of different classification problems. We characterize datasets sampled from six classification problems by performance ranks of simple classifiers, and define the similarity by the inverse of Euclidean distance in this meta-feature space. We visualize the similarities in a 2D space, where meaningful clusters start to emerge, and show that the proposed representation can be used to classify datasets according to their origin with 89.3\% accuracy. These findings, together with the observations of recent trends in machine learning, suggest that meta-learning could be a valuable tool for the medical imaging community.
[ { "version": "v1", "created": "Mon, 12 Jun 2017 08:28:17 GMT" } ]
2017-06-13T00:00:00
[ [ "Cheplygina", "Veronika", "" ], [ "Moeskops", "Pim", "" ], [ "Veta", "Mitko", "" ], [ "Bozorg", "Behdad Dasht", "" ], [ "Pluim", "Josien", "" ] ]
TITLE: Exploring the similarity of medical imaging classification problems ABSTRACT: Supervised learning is ubiquitous in medical image analysis. In this paper we consider the problem of meta-learning -- predicting which methods will perform well in an unseen classification problem, given previous experience with other classification problems. We investigate the first step of such an approach: how to quantify the similarity of different classification problems. We characterize datasets sampled from six classification problems by performance ranks of simple classifiers, and define the similarity by the inverse of Euclidean distance in this meta-feature space. We visualize the similarities in a 2D space, where meaningful clusters start to emerge, and show that the proposed representation can be used to classify datasets according to their origin with 89.3\% accuracy. These findings, together with the observations of recent trends in machine learning, suggest that meta-learning could be a valuable tool for the medical imaging community.
no_new_dataset
0.948155
1706.03581
Artsiom Ablavatski
Artsiom Ablavatski, Shijian Lu and Jianfei Cai
Enriched Deep Recurrent Visual Attention Model for Multiple Object Recognition
null
null
10.1109/WACV.2017.113
null
cs.CV cs.LG
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We design an Enriched Deep Recurrent Visual Attention Model (EDRAM) - an improved attention-based architecture for multiple object recognition. The proposed model is a fully differentiable unit that can be optimized end-to-end by using Stochastic Gradient Descent (SGD). The Spatial Transformer (ST) was employed as visual attention mechanism which allows to learn the geometric transformation of objects within images. With the combination of the Spatial Transformer and the powerful recurrent architecture, the proposed EDRAM can localize and recognize objects simultaneously. EDRAM has been evaluated on two publicly available datasets including MNIST Cluttered (with 70K cluttered digits) and SVHN (with up to 250k real world images of house numbers). Experiments show that it obtains superior performance as compared with the state-of-the-art models.
[ { "version": "v1", "created": "Mon, 12 Jun 2017 11:55:35 GMT" } ]
2017-06-13T00:00:00
[ [ "Ablavatski", "Artsiom", "" ], [ "Lu", "Shijian", "" ], [ "Cai", "Jianfei", "" ] ]
TITLE: Enriched Deep Recurrent Visual Attention Model for Multiple Object Recognition ABSTRACT: We design an Enriched Deep Recurrent Visual Attention Model (EDRAM) - an improved attention-based architecture for multiple object recognition. The proposed model is a fully differentiable unit that can be optimized end-to-end by using Stochastic Gradient Descent (SGD). The Spatial Transformer (ST) was employed as visual attention mechanism which allows to learn the geometric transformation of objects within images. With the combination of the Spatial Transformer and the powerful recurrent architecture, the proposed EDRAM can localize and recognize objects simultaneously. EDRAM has been evaluated on two publicly available datasets including MNIST Cluttered (with 70K cluttered digits) and SVHN (with up to 250k real world images of house numbers). Experiments show that it obtains superior performance as compared with the state-of-the-art models.
no_new_dataset
0.947332
1706.03725
Zhiyuan Shi
Zhiyuan Shi, Timothy M. Hospedales, Tao Xiang
Transferring a Semantic Representation for Person Re-Identification and Search
cvpr 2015
null
null
null
cs.CV
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Learning semantic attributes for person re-identification and description-based person search has gained increasing interest due to attributes' great potential as a pose and view-invariant representation. However, existing attribute-centric approaches have thus far underperformed state-of-the-art conventional approaches. This is due to their non-scalable need for extensive domain (camera) specific annotation. In this paper we present a new semantic attribute learning approach for person re-identification and search. Our model is trained on existing fashion photography datasets -- either weakly or strongly labelled. It can then be transferred and adapted to provide a powerful semantic description of surveillance person detections, without requiring any surveillance domain supervision. The resulting representation is useful for both unsupervised and supervised person re-identification, achieving state-of-the-art and near state-of-the-art performance respectively. Furthermore, as a semantic representation it allows description-based person search to be integrated within the same framework.
[ { "version": "v1", "created": "Mon, 12 Jun 2017 16:52:57 GMT" } ]
2017-06-13T00:00:00
[ [ "Shi", "Zhiyuan", "" ], [ "Hospedales", "Timothy M.", "" ], [ "Xiang", "Tao", "" ] ]
TITLE: Transferring a Semantic Representation for Person Re-Identification and Search ABSTRACT: Learning semantic attributes for person re-identification and description-based person search has gained increasing interest due to attributes' great potential as a pose and view-invariant representation. However, existing attribute-centric approaches have thus far underperformed state-of-the-art conventional approaches. This is due to their non-scalable need for extensive domain (camera) specific annotation. In this paper we present a new semantic attribute learning approach for person re-identification and search. Our model is trained on existing fashion photography datasets -- either weakly or strongly labelled. It can then be transferred and adapted to provide a powerful semantic description of surveillance person detections, without requiring any surveillance domain supervision. The resulting representation is useful for both unsupervised and supervised person re-identification, achieving state-of-the-art and near state-of-the-art performance respectively. Furthermore, as a semantic representation it allows description-based person search to be integrated within the same framework.
no_new_dataset
0.947817
1507.05738
Serena Yeung
Serena Yeung, Olga Russakovsky, Ning Jin, Mykhaylo Andriluka, Greg Mori, Li Fei-Fei
Every Moment Counts: Dense Detailed Labeling of Actions in Complex Videos
To appear in IJCV
null
null
null
cs.CV
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Every moment counts in action recognition. A comprehensive understanding of human activity in video requires labeling every frame according to the actions occurring, placing multiple labels densely over a video sequence. To study this problem we extend the existing THUMOS dataset and introduce MultiTHUMOS, a new dataset of dense labels over unconstrained internet videos. Modeling multiple, dense labels benefits from temporal relations within and across classes. We define a novel variant of long short-term memory (LSTM) deep networks for modeling these temporal relations via multiple input and output connections. We show that this model improves action labeling accuracy and further enables deeper understanding tasks ranging from structured retrieval to action prediction.
[ { "version": "v1", "created": "Tue, 21 Jul 2015 08:07:50 GMT" }, { "version": "v2", "created": "Fri, 31 Jul 2015 22:09:30 GMT" }, { "version": "v3", "created": "Fri, 9 Jun 2017 10:42:09 GMT" } ]
2017-06-12T00:00:00
[ [ "Yeung", "Serena", "" ], [ "Russakovsky", "Olga", "" ], [ "Jin", "Ning", "" ], [ "Andriluka", "Mykhaylo", "" ], [ "Mori", "Greg", "" ], [ "Fei-Fei", "Li", "" ] ]
TITLE: Every Moment Counts: Dense Detailed Labeling of Actions in Complex Videos ABSTRACT: Every moment counts in action recognition. A comprehensive understanding of human activity in video requires labeling every frame according to the actions occurring, placing multiple labels densely over a video sequence. To study this problem we extend the existing THUMOS dataset and introduce MultiTHUMOS, a new dataset of dense labels over unconstrained internet videos. Modeling multiple, dense labels benefits from temporal relations within and across classes. We define a novel variant of long short-term memory (LSTM) deep networks for modeling these temporal relations via multiple input and output connections. We show that this model improves action labeling accuracy and further enables deeper understanding tasks ranging from structured retrieval to action prediction.
new_dataset
0.951818
1605.09068
Michael Lash
Michael T. Lash, Qihang Lin, W. Nick Street and Jennifer G. Robinson
A budget-constrained inverse classification framework for smooth classifiers
null
null
null
null
cs.LG stat.ML
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Inverse classification is the process of manipulating an instance such that it is more likely to conform to a specific class. Past methods that address such a problem have shortcomings. Greedy methods make changes that are overly radical, often relying on data that is strictly discrete. Other methods rely on certain data points, the presence of which cannot be guaranteed. In this paper we propose a general framework and method that overcomes these and other limitations. The formulation of our method can use any differentiable classification function. We demonstrate the method by using logistic regression and Gaussian kernel SVMs. We constrain the inverse classification to occur on features that can actually be changed, each of which incurs an individual cost. We further subject such changes to fall within a certain level of cumulative change (budget). Our framework can also accommodate the estimation of (indirectly changeable) features whose values change as a consequence of actions taken. Furthermore, we propose two methods for specifying feature-value ranges that result in different algorithmic behavior. We apply our method, and a proposed sensitivity analysis-based benchmark method, to two freely available datasets: Student Performance from the UCI Machine Learning Repository and a real world cardiovascular disease dataset. The results obtained demonstrate the validity and benefits of our framework and method.
[ { "version": "v1", "created": "Sun, 29 May 2016 21:50:25 GMT" }, { "version": "v2", "created": "Sat, 18 Feb 2017 22:30:53 GMT" }, { "version": "v3", "created": "Thu, 8 Jun 2017 18:27:39 GMT" } ]
2017-06-12T00:00:00
[ [ "Lash", "Michael T.", "" ], [ "Lin", "Qihang", "" ], [ "Street", "W. Nick", "" ], [ "Robinson", "Jennifer G.", "" ] ]
TITLE: A budget-constrained inverse classification framework for smooth classifiers ABSTRACT: Inverse classification is the process of manipulating an instance such that it is more likely to conform to a specific class. Past methods that address such a problem have shortcomings. Greedy methods make changes that are overly radical, often relying on data that is strictly discrete. Other methods rely on certain data points, the presence of which cannot be guaranteed. In this paper we propose a general framework and method that overcomes these and other limitations. The formulation of our method can use any differentiable classification function. We demonstrate the method by using logistic regression and Gaussian kernel SVMs. We constrain the inverse classification to occur on features that can actually be changed, each of which incurs an individual cost. We further subject such changes to fall within a certain level of cumulative change (budget). Our framework can also accommodate the estimation of (indirectly changeable) features whose values change as a consequence of actions taken. Furthermore, we propose two methods for specifying feature-value ranges that result in different algorithmic behavior. We apply our method, and a proposed sensitivity analysis-based benchmark method, to two freely available datasets: Student Performance from the UCI Machine Learning Repository and a real world cardiovascular disease dataset. The results obtained demonstrate the validity and benefits of our framework and method.
no_new_dataset
0.938913
1611.05424
Alejandro Newell
Alejandro Newell, Zhiao Huang, Jia Deng
Associative Embedding: End-to-End Learning for Joint Detection and Grouping
Added results on MS-COCO and updated results on MPII
null
null
null
cs.CV
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We introduce associative embedding, a novel method for supervising convolutional neural networks for the task of detection and grouping. A number of computer vision problems can be framed in this manner including multi-person pose estimation, instance segmentation, and multi-object tracking. Usually the grouping of detections is achieved with multi-stage pipelines, instead we propose an approach that teaches a network to simultaneously output detections and group assignments. This technique can be easily integrated into any state-of-the-art network architecture that produces pixel-wise predictions. We show how to apply this method to both multi-person pose estimation and instance segmentation and report state-of-the-art performance for multi-person pose on the MPII and MS-COCO datasets.
[ { "version": "v1", "created": "Wed, 16 Nov 2016 20:04:28 GMT" }, { "version": "v2", "created": "Fri, 9 Jun 2017 16:13:48 GMT" } ]
2017-06-12T00:00:00
[ [ "Newell", "Alejandro", "" ], [ "Huang", "Zhiao", "" ], [ "Deng", "Jia", "" ] ]
TITLE: Associative Embedding: End-to-End Learning for Joint Detection and Grouping ABSTRACT: We introduce associative embedding, a novel method for supervising convolutional neural networks for the task of detection and grouping. A number of computer vision problems can be framed in this manner including multi-person pose estimation, instance segmentation, and multi-object tracking. Usually the grouping of detections is achieved with multi-stage pipelines, instead we propose an approach that teaches a network to simultaneously output detections and group assignments. This technique can be easily integrated into any state-of-the-art network architecture that produces pixel-wise predictions. We show how to apply this method to both multi-person pose estimation and instance segmentation and report state-of-the-art performance for multi-person pose on the MPII and MS-COCO datasets.
no_new_dataset
0.947624
1611.06440
Pavlo Molchanov
Pavlo Molchanov, Stephen Tyree, Tero Karras, Timo Aila, Jan Kautz
Pruning Convolutional Neural Networks for Resource Efficient Inference
17 pages, 14 figures, ICLR 2017 paper
null
null
null
cs.LG stat.ML
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We propose a new formulation for pruning convolutional kernels in neural networks to enable efficient inference. We interleave greedy criteria-based pruning with fine-tuning by backpropagation - a computationally efficient procedure that maintains good generalization in the pruned network. We propose a new criterion based on Taylor expansion that approximates the change in the cost function induced by pruning network parameters. We focus on transfer learning, where large pretrained networks are adapted to specialized tasks. The proposed criterion demonstrates superior performance compared to other criteria, e.g. the norm of kernel weights or feature map activation, for pruning large CNNs after adaptation to fine-grained classification tasks (Birds-200 and Flowers-102) relaying only on the first order gradient information. We also show that pruning can lead to more than 10x theoretical (5x practical) reduction in adapted 3D-convolutional filters with a small drop in accuracy in a recurrent gesture classifier. Finally, we show results for the large-scale ImageNet dataset to emphasize the flexibility of our approach.
[ { "version": "v1", "created": "Sat, 19 Nov 2016 22:48:30 GMT" }, { "version": "v2", "created": "Thu, 8 Jun 2017 19:53:26 GMT" } ]
2017-06-12T00:00:00
[ [ "Molchanov", "Pavlo", "" ], [ "Tyree", "Stephen", "" ], [ "Karras", "Tero", "" ], [ "Aila", "Timo", "" ], [ "Kautz", "Jan", "" ] ]
TITLE: Pruning Convolutional Neural Networks for Resource Efficient Inference ABSTRACT: We propose a new formulation for pruning convolutional kernels in neural networks to enable efficient inference. We interleave greedy criteria-based pruning with fine-tuning by backpropagation - a computationally efficient procedure that maintains good generalization in the pruned network. We propose a new criterion based on Taylor expansion that approximates the change in the cost function induced by pruning network parameters. We focus on transfer learning, where large pretrained networks are adapted to specialized tasks. The proposed criterion demonstrates superior performance compared to other criteria, e.g. the norm of kernel weights or feature map activation, for pruning large CNNs after adaptation to fine-grained classification tasks (Birds-200 and Flowers-102) relaying only on the first order gradient information. We also show that pruning can lead to more than 10x theoretical (5x practical) reduction in adapted 3D-convolutional filters with a small drop in accuracy in a recurrent gesture classifier. Finally, we show results for the large-scale ImageNet dataset to emphasize the flexibility of our approach.
no_new_dataset
0.948728
1702.07944
Simon Du
Simon S. Du, Jianshu Chen, Lihong Li, Lin Xiao, Dengyong Zhou
Stochastic Variance Reduction Methods for Policy Evaluation
Accepted by ICML 2017
null
null
null
cs.LG cs.AI cs.SY math.OC stat.ML
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Policy evaluation is a crucial step in many reinforcement-learning procedures, which estimates a value function that predicts states' long-term value under a given policy. In this paper, we focus on policy evaluation with linear function approximation over a fixed dataset. We first transform the empirical policy evaluation problem into a (quadratic) convex-concave saddle point problem, and then present a primal-dual batch gradient method, as well as two stochastic variance reduction methods for solving the problem. These algorithms scale linearly in both sample size and feature dimension. Moreover, they achieve linear convergence even when the saddle-point problem has only strong concavity in the dual variables but no strong convexity in the primal variables. Numerical experiments on benchmark problems demonstrate the effectiveness of our methods.
[ { "version": "v1", "created": "Sat, 25 Feb 2017 20:15:55 GMT" }, { "version": "v2", "created": "Fri, 9 Jun 2017 06:02:47 GMT" } ]
2017-06-12T00:00:00
[ [ "Du", "Simon S.", "" ], [ "Chen", "Jianshu", "" ], [ "Li", "Lihong", "" ], [ "Xiao", "Lin", "" ], [ "Zhou", "Dengyong", "" ] ]
TITLE: Stochastic Variance Reduction Methods for Policy Evaluation ABSTRACT: Policy evaluation is a crucial step in many reinforcement-learning procedures, which estimates a value function that predicts states' long-term value under a given policy. In this paper, we focus on policy evaluation with linear function approximation over a fixed dataset. We first transform the empirical policy evaluation problem into a (quadratic) convex-concave saddle point problem, and then present a primal-dual batch gradient method, as well as two stochastic variance reduction methods for solving the problem. These algorithms scale linearly in both sample size and feature dimension. Moreover, they achieve linear convergence even when the saddle-point problem has only strong concavity in the dual variables but no strong convexity in the primal variables. Numerical experiments on benchmark problems demonstrate the effectiveness of our methods.
no_new_dataset
0.950319
1702.08396
Shengjia Zhao
Shengjia Zhao, Jiaming Song, Stefano Ermon
Learning Hierarchical Features from Generative Models
ICML'2017
null
null
null
cs.LG stat.ML
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Deep neural networks have been shown to be very successful at learning feature hierarchies in supervised learning tasks. Generative models, on the other hand, have benefited less from hierarchical models with multiple layers of latent variables. In this paper, we prove that hierarchical latent variable models do not take advantage of the hierarchical structure when trained with existing variational methods, and provide some limitations on the kind of features existing models can learn. Finally we propose an alternative architecture that do not suffer from these limitations. Our model is able to learn highly interpretable and disentangled hierarchical features on several natural image datasets with no task specific regularization or prior knowledge.
[ { "version": "v1", "created": "Mon, 27 Feb 2017 17:43:34 GMT" }, { "version": "v2", "created": "Fri, 9 Jun 2017 17:19:15 GMT" } ]
2017-06-12T00:00:00
[ [ "Zhao", "Shengjia", "" ], [ "Song", "Jiaming", "" ], [ "Ermon", "Stefano", "" ] ]
TITLE: Learning Hierarchical Features from Generative Models ABSTRACT: Deep neural networks have been shown to be very successful at learning feature hierarchies in supervised learning tasks. Generative models, on the other hand, have benefited less from hierarchical models with multiple layers of latent variables. In this paper, we prove that hierarchical latent variable models do not take advantage of the hierarchical structure when trained with existing variational methods, and provide some limitations on the kind of features existing models can learn. Finally we propose an alternative architecture that do not suffer from these limitations. Our model is able to learn highly interpretable and disentangled hierarchical features on several natural image datasets with no task specific regularization or prior knowledge.
no_new_dataset
0.944842
1705.04416
Joshua Peterson
Dawn Chen, Joshua C. Peterson, Thomas L. Griffiths
Evaluating vector-space models of analogy
6 pages, 4 figures, In the Proceedings of the 39th Annual Conference of the Cognitive Science Society
null
null
null
cs.CL
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Vector-space representations provide geometric tools for reasoning about the similarity of a set of objects and their relationships. Recent machine learning methods for deriving vector-space embeddings of words (e.g., word2vec) have achieved considerable success in natural language processing. These vector spaces have also been shown to exhibit a surprising capacity to capture verbal analogies, with similar results for natural images, giving new life to a classic model of analogies as parallelograms that was first proposed by cognitive scientists. We evaluate the parallelogram model of analogy as applied to modern word embeddings, providing a detailed analysis of the extent to which this approach captures human relational similarity judgments in a large benchmark dataset. We find that that some semantic relationships are better captured than others. We then provide evidence for deeper limitations of the parallelogram model based on the intrinsic geometric constraints of vector spaces, paralleling classic results for first-order similarity.
[ { "version": "v1", "created": "Fri, 12 May 2017 01:26:23 GMT" }, { "version": "v2", "created": "Thu, 8 Jun 2017 20:52:12 GMT" } ]
2017-06-12T00:00:00
[ [ "Chen", "Dawn", "" ], [ "Peterson", "Joshua C.", "" ], [ "Griffiths", "Thomas L.", "" ] ]
TITLE: Evaluating vector-space models of analogy ABSTRACT: Vector-space representations provide geometric tools for reasoning about the similarity of a set of objects and their relationships. Recent machine learning methods for deriving vector-space embeddings of words (e.g., word2vec) have achieved considerable success in natural language processing. These vector spaces have also been shown to exhibit a surprising capacity to capture verbal analogies, with similar results for natural images, giving new life to a classic model of analogies as parallelograms that was first proposed by cognitive scientists. We evaluate the parallelogram model of analogy as applied to modern word embeddings, providing a detailed analysis of the extent to which this approach captures human relational similarity judgments in a large benchmark dataset. We find that that some semantic relationships are better captured than others. We then provide evidence for deeper limitations of the parallelogram model based on the intrinsic geometric constraints of vector spaces, paralleling classic results for first-order similarity.
no_new_dataset
0.951233
1706.02384
Virag Shah
Virag Shah, Anne Bouillard, Francois Baccelli
Delay Comparison of Delivery and Coding Policies in Data Clusters
13 pages, 4 figures
null
null
null
cs.PF
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
A key function of cloud infrastructure is to store and deliver diverse files, e.g., scientific datasets, social network information, videos, etc. In such systems, for the purpose of fast and reliable delivery, files are divided into chunks, replicated or erasure-coded, and disseminated across servers. It is neither known in general how delays scale with the size of a request nor how delays compare under different policies for coding, data dissemination, and delivery. Motivated by these questions, we develop and explore a set of evolution equations as a unified model which captures the above features. These equations allow for both efficient simulation and mathematical analysis of several delivery policies under general statistical assumptions. In particular, we quantify in what sense a workload aware delivery policy performs better than a workload agnostic policy. Under a dynamic or stochastic setting, the sample path comparison of these policies does not hold in general. The comparison is shown to hold under the weaker increasing convex stochastic ordering, still stronger than the comparison of averages. This result further allows us to obtain insightful computable performance bounds. For example, we show that in a system where files are divided into chunks of equal size, replicated or erasure-coded, and disseminated across servers at random, the job delays increase sub-logarithmically in the request size for small and medium-sized files but linearly for large files.
[ { "version": "v1", "created": "Wed, 7 Jun 2017 21:27:04 GMT" }, { "version": "v2", "created": "Fri, 9 Jun 2017 14:35:54 GMT" } ]
2017-06-12T00:00:00
[ [ "Shah", "Virag", "" ], [ "Bouillard", "Anne", "" ], [ "Baccelli", "Francois", "" ] ]
TITLE: Delay Comparison of Delivery and Coding Policies in Data Clusters ABSTRACT: A key function of cloud infrastructure is to store and deliver diverse files, e.g., scientific datasets, social network information, videos, etc. In such systems, for the purpose of fast and reliable delivery, files are divided into chunks, replicated or erasure-coded, and disseminated across servers. It is neither known in general how delays scale with the size of a request nor how delays compare under different policies for coding, data dissemination, and delivery. Motivated by these questions, we develop and explore a set of evolution equations as a unified model which captures the above features. These equations allow for both efficient simulation and mathematical analysis of several delivery policies under general statistical assumptions. In particular, we quantify in what sense a workload aware delivery policy performs better than a workload agnostic policy. Under a dynamic or stochastic setting, the sample path comparison of these policies does not hold in general. The comparison is shown to hold under the weaker increasing convex stochastic ordering, still stronger than the comparison of averages. This result further allows us to obtain insightful computable performance bounds. For example, we show that in a system where files are divided into chunks of equal size, replicated or erasure-coded, and disseminated across servers at random, the job delays increase sub-logarithmically in the request size for small and medium-sized files but linearly for large files.
no_new_dataset
0.946843
1706.02493
Zhe Wang
Zhe Wang, Hongsheng Li, Wanli Ouyang, and Xiaogang Wang
Learning Deep Representations for Scene Labeling with Semantic Context Guided Supervision
13 pages
null
null
null
cs.CV
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Scene labeling is a challenging classification problem where each input image requires a pixel-level prediction map. Recently, deep-learning-based methods have shown their effectiveness on solving this problem. However, we argue that the large intra-class variation provides ambiguous training information and hinders the deep models' ability to learn more discriminative deep feature representations. Unlike existing methods that mainly utilize semantic context for regularizing or smoothing the prediction map, we design novel supervisions from semantic context for learning better deep feature representations. Two types of semantic context, scene names of images and label map statistics of image patches, are exploited to create label hierarchies between the original classes and newly created subclasses as the learning supervisions. Such subclasses show lower intra-class variation, and help CNN detect more meaningful visual patterns and learn more effective deep features. Novel training strategies and network structure that take advantages of such label hierarchies are introduced. Our proposed method is evaluated extensively on four popular datasets, Stanford Background (8 classes), SIFTFlow (33 classes), Barcelona (170 classes) and LM+Sun datasets (232 classes) with 3 different networks structures, and show state-of-the-art performance. The experiments show that our proposed method makes deep models learn more discriminative feature representations without increasing model size or complexity.
[ { "version": "v1", "created": "Thu, 8 Jun 2017 09:44:00 GMT" }, { "version": "v2", "created": "Fri, 9 Jun 2017 04:15:55 GMT" } ]
2017-06-12T00:00:00
[ [ "Wang", "Zhe", "" ], [ "Li", "Hongsheng", "" ], [ "Ouyang", "Wanli", "" ], [ "Wang", "Xiaogang", "" ] ]
TITLE: Learning Deep Representations for Scene Labeling with Semantic Context Guided Supervision ABSTRACT: Scene labeling is a challenging classification problem where each input image requires a pixel-level prediction map. Recently, deep-learning-based methods have shown their effectiveness on solving this problem. However, we argue that the large intra-class variation provides ambiguous training information and hinders the deep models' ability to learn more discriminative deep feature representations. Unlike existing methods that mainly utilize semantic context for regularizing or smoothing the prediction map, we design novel supervisions from semantic context for learning better deep feature representations. Two types of semantic context, scene names of images and label map statistics of image patches, are exploited to create label hierarchies between the original classes and newly created subclasses as the learning supervisions. Such subclasses show lower intra-class variation, and help CNN detect more meaningful visual patterns and learn more effective deep features. Novel training strategies and network structure that take advantages of such label hierarchies are introduced. Our proposed method is evaluated extensively on four popular datasets, Stanford Background (8 classes), SIFTFlow (33 classes), Barcelona (170 classes) and LM+Sun datasets (232 classes) with 3 different networks structures, and show state-of-the-art performance. The experiments show that our proposed method makes deep models learn more discriminative feature representations without increasing model size or complexity.
no_new_dataset
0.951414
1706.02863
Shuo Yang
Shuo Yang, Yuanjun Xiong, Chen Change Loy, Xiaoou Tang
Face Detection through Scale-Friendly Deep Convolutional Networks
12 pages, 10 figures
null
null
null
cs.CV
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
In this paper, we share our experience in designing a convolutional network-based face detector that could handle faces of an extremely wide range of scales. We show that faces with different scales can be modeled through a specialized set of deep convolutional networks with different structures. These detectors can be seamlessly integrated into a single unified network that can be trained end-to-end. In contrast to existing deep models that are designed for wide scale range, our network does not require an image pyramid input and the model is of modest complexity. Our network, dubbed ScaleFace, achieves promising performance on WIDER FACE and FDDB datasets with practical runtime speed. Specifically, our method achieves 76.4 average precision on the challenging WIDER FACE dataset and 96% recall rate on the FDDB dataset with 7 frames per second (fps) for 900 * 1300 input image.
[ { "version": "v1", "created": "Fri, 9 Jun 2017 08:20:56 GMT" } ]
2017-06-12T00:00:00
[ [ "Yang", "Shuo", "" ], [ "Xiong", "Yuanjun", "" ], [ "Loy", "Chen Change", "" ], [ "Tang", "Xiaoou", "" ] ]
TITLE: Face Detection through Scale-Friendly Deep Convolutional Networks ABSTRACT: In this paper, we share our experience in designing a convolutional network-based face detector that could handle faces of an extremely wide range of scales. We show that faces with different scales can be modeled through a specialized set of deep convolutional networks with different structures. These detectors can be seamlessly integrated into a single unified network that can be trained end-to-end. In contrast to existing deep models that are designed for wide scale range, our network does not require an image pyramid input and the model is of modest complexity. Our network, dubbed ScaleFace, achieves promising performance on WIDER FACE and FDDB datasets with practical runtime speed. Specifically, our method achieves 76.4 average precision on the challenging WIDER FACE dataset and 96% recall rate on the FDDB dataset with 7 frames per second (fps) for 900 * 1300 input image.
no_new_dataset
0.954732
1706.02867
Milad Niknejad
Milad Niknejad, Jose M. Bioucas-Dias, Mario A. T. Figueiredo
Class-specific Poisson denoising by patch-based importance sampling
null
null
null
null
cs.CV
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
In this paper, we address the problem of recovering images degraded by Poisson noise, where the image is known to belong to a specific class. In the proposed method, a dataset of clean patches from images of the class of interest is clustered using multivariate Gaussian distributions. In order to recover the noisy image, each noisy patch is assigned to one of these distributions, and the corresponding minimum mean squared error (MMSE) estimate is obtained. We propose to use a self-normalized importance sampling approach, which is a method of the Monte-Carlo family, for the both determining the most likely distribution and approximating the MMSE estimate of the clean patch. Experimental results shows that our proposed method outperforms other methods for Poisson denoising at a low SNR regime.
[ { "version": "v1", "created": "Fri, 9 Jun 2017 08:47:26 GMT" } ]
2017-06-12T00:00:00
[ [ "Niknejad", "Milad", "" ], [ "Bioucas-Dias", "Jose M.", "" ], [ "Figueiredo", "Mario A. T.", "" ] ]
TITLE: Class-specific Poisson denoising by patch-based importance sampling ABSTRACT: In this paper, we address the problem of recovering images degraded by Poisson noise, where the image is known to belong to a specific class. In the proposed method, a dataset of clean patches from images of the class of interest is clustered using multivariate Gaussian distributions. In order to recover the noisy image, each noisy patch is assigned to one of these distributions, and the corresponding minimum mean squared error (MMSE) estimate is obtained. We propose to use a self-normalized importance sampling approach, which is a method of the Monte-Carlo family, for the both determining the most likely distribution and approximating the MMSE estimate of the clean patch. Experimental results shows that our proposed method outperforms other methods for Poisson denoising at a low SNR regime.
no_new_dataset
0.945349
1706.02883
Jingjing Gong
Xipeng Qiu, Jingjing Gong, Xuanjing Huang
Overview of the NLPCC 2017 Shared Task: Chinese News Headline Categorization
null
null
null
null
cs.CL
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
In this paper, we give an overview for the shared task at the CCF Conference on Natural Language Processing \& Chinese Computing (NLPCC 2017): Chinese News Headline Categorization. The dataset of this shared task consists 18 classes, 12,000 short texts along with corresponded labels for each class. The dataset and example code can be accessed at https://github.com/FudanNLP/nlpcc2017_news_headline_categorization.
[ { "version": "v1", "created": "Fri, 9 Jun 2017 10:17:24 GMT" } ]
2017-06-12T00:00:00
[ [ "Qiu", "Xipeng", "" ], [ "Gong", "Jingjing", "" ], [ "Huang", "Xuanjing", "" ] ]
TITLE: Overview of the NLPCC 2017 Shared Task: Chinese News Headline Categorization ABSTRACT: In this paper, we give an overview for the shared task at the CCF Conference on Natural Language Processing \& Chinese Computing (NLPCC 2017): Chinese News Headline Categorization. The dataset of this shared task consists 18 classes, 12,000 short texts along with corresponded labels for each class. The dataset and example code can be accessed at https://github.com/FudanNLP/nlpcc2017_news_headline_categorization.
new_dataset
0.788909
1706.02884
Serena Yeung
Serena Yeung, Vignesh Ramanathan, Olga Russakovsky, Liyue Shen, Greg Mori, Li Fei-Fei
Learning to Learn from Noisy Web Videos
To appear in CVPR 2017
null
null
null
cs.CV
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Understanding the simultaneously very diverse and intricately fine-grained set of possible human actions is a critical open problem in computer vision. Manually labeling training videos is feasible for some action classes but doesn't scale to the full long-tailed distribution of actions. A promising way to address this is to leverage noisy data from web queries to learn new actions, using semi-supervised or "webly-supervised" approaches. However, these methods typically do not learn domain-specific knowledge, or rely on iterative hand-tuned data labeling policies. In this work, we instead propose a reinforcement learning-based formulation for selecting the right examples for training a classifier from noisy web search results. Our method uses Q-learning to learn a data labeling policy on a small labeled training dataset, and then uses this to automatically label noisy web data for new visual concepts. Experiments on the challenging Sports-1M action recognition benchmark as well as on additional fine-grained and newly emerging action classes demonstrate that our method is able to learn good labeling policies for noisy data and use this to learn accurate visual concept classifiers.
[ { "version": "v1", "created": "Fri, 9 Jun 2017 10:25:05 GMT" } ]
2017-06-12T00:00:00
[ [ "Yeung", "Serena", "" ], [ "Ramanathan", "Vignesh", "" ], [ "Russakovsky", "Olga", "" ], [ "Shen", "Liyue", "" ], [ "Mori", "Greg", "" ], [ "Fei-Fei", "Li", "" ] ]
TITLE: Learning to Learn from Noisy Web Videos ABSTRACT: Understanding the simultaneously very diverse and intricately fine-grained set of possible human actions is a critical open problem in computer vision. Manually labeling training videos is feasible for some action classes but doesn't scale to the full long-tailed distribution of actions. A promising way to address this is to leverage noisy data from web queries to learn new actions, using semi-supervised or "webly-supervised" approaches. However, these methods typically do not learn domain-specific knowledge, or rely on iterative hand-tuned data labeling policies. In this work, we instead propose a reinforcement learning-based formulation for selecting the right examples for training a classifier from noisy web search results. Our method uses Q-learning to learn a data labeling policy on a small labeled training dataset, and then uses this to automatically label noisy web data for new visual concepts. Experiments on the challenging Sports-1M action recognition benchmark as well as on additional fine-grained and newly emerging action classes demonstrate that our method is able to learn good labeling policies for noisy data and use this to learn accurate visual concept classifiers.
no_new_dataset
0.947769
1706.02897
Djallel Bouneffouf
Djallel Bouneffouf, Irina Rish, Guillermo A. Cecchi
Bandit Models of Human Behavior: Reward Processing in Mental Disorders
Conference on Artificial General Intelligence, AGI-17
null
null
null
cs.AI
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Drawing an inspiration from behavioral studies of human decision making, we propose here a general parametric framework for multi-armed bandit problem, which extends the standard Thompson Sampling approach to incorporate reward processing biases associated with several neurological and psychiatric conditions, including Parkinson's and Alzheimer's diseases, attention-deficit/hyperactivity disorder (ADHD), addiction, and chronic pain. We demonstrate empirically that the proposed parametric approach can often outperform the baseline Thompson Sampling on a variety of datasets. Moreover, from the behavioral modeling perspective, our parametric framework can be viewed as a first step towards a unifying computational model capturing reward processing abnormalities across multiple mental conditions.
[ { "version": "v1", "created": "Wed, 7 Jun 2017 18:36:12 GMT" } ]
2017-06-12T00:00:00
[ [ "Bouneffouf", "Djallel", "" ], [ "Rish", "Irina", "" ], [ "Cecchi", "Guillermo A.", "" ] ]
TITLE: Bandit Models of Human Behavior: Reward Processing in Mental Disorders ABSTRACT: Drawing an inspiration from behavioral studies of human decision making, we propose here a general parametric framework for multi-armed bandit problem, which extends the standard Thompson Sampling approach to incorporate reward processing biases associated with several neurological and psychiatric conditions, including Parkinson's and Alzheimer's diseases, attention-deficit/hyperactivity disorder (ADHD), addiction, and chronic pain. We demonstrate empirically that the proposed parametric approach can often outperform the baseline Thompson Sampling on a variety of datasets. Moreover, from the behavioral modeling perspective, our parametric framework can be viewed as a first step towards a unifying computational model capturing reward processing abnormalities across multiple mental conditions.
no_new_dataset
0.938407
1706.03015
Jie Miao
Jie Miao, Xiangmin Xu, Xiaofen Xing, Dacheng Tao
Manifold Regularized Slow Feature Analysis for Dynamic Texture Recognition
12 pages
null
null
null
cs.CV
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Dynamic textures exist in various forms, e.g., fire, smoke, and traffic jams, but recognizing dynamic texture is challenging due to the complex temporal variations. In this paper, we present a novel approach stemmed from slow feature analysis (SFA) for dynamic texture recognition. SFA extracts slowly varying features from fast varying signals. Fortunately, SFA is capable to leach invariant representations from dynamic textures. However, complex temporal variations require high-level semantic representations to fully achieve temporal slowness, and thus it is impractical to learn a high-level representation from dynamic textures directly by SFA. In order to learn a robust low-level feature to resolve the complexity of dynamic textures, we propose manifold regularized SFA (MR-SFA) by exploring the neighbor relationship of the initial state of each temporal transition and retaining the locality of their variations. Therefore, the learned features are not only slowly varying, but also partly predictable. MR-SFA for dynamic texture recognition is proposed in the following steps: 1) learning feature extraction functions as convolution filters by MR-SFA, 2) extracting local features by convolution and pooling, and 3) employing Fisher vectors to form a video-level representation for classification. Experimental results on dynamic texture and dynamic scene recognition datasets validate the effectiveness of the proposed approach.
[ { "version": "v1", "created": "Fri, 9 Jun 2017 16:06:25 GMT" } ]
2017-06-12T00:00:00
[ [ "Miao", "Jie", "" ], [ "Xu", "Xiangmin", "" ], [ "Xing", "Xiaofen", "" ], [ "Tao", "Dacheng", "" ] ]
TITLE: Manifold Regularized Slow Feature Analysis for Dynamic Texture Recognition ABSTRACT: Dynamic textures exist in various forms, e.g., fire, smoke, and traffic jams, but recognizing dynamic texture is challenging due to the complex temporal variations. In this paper, we present a novel approach stemmed from slow feature analysis (SFA) for dynamic texture recognition. SFA extracts slowly varying features from fast varying signals. Fortunately, SFA is capable to leach invariant representations from dynamic textures. However, complex temporal variations require high-level semantic representations to fully achieve temporal slowness, and thus it is impractical to learn a high-level representation from dynamic textures directly by SFA. In order to learn a robust low-level feature to resolve the complexity of dynamic textures, we propose manifold regularized SFA (MR-SFA) by exploring the neighbor relationship of the initial state of each temporal transition and retaining the locality of their variations. Therefore, the learned features are not only slowly varying, but also partly predictable. MR-SFA for dynamic texture recognition is proposed in the following steps: 1) learning feature extraction functions as convolution filters by MR-SFA, 2) extracting local features by convolution and pooling, and 3) employing Fisher vectors to form a video-level representation for classification. Experimental results on dynamic texture and dynamic scene recognition datasets validate the effectiveness of the proposed approach.
no_new_dataset
0.946794
1703.04816
Dirk Weissenborn
Dirk Weissenborn and Georg Wiese and Laura Seiffe
Making Neural QA as Simple as Possible but not Simpler
null
null
null
null
cs.CL cs.AI cs.NE
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Recent development of large-scale question answering (QA) datasets triggered a substantial amount of research into end-to-end neural architectures for QA. Increasingly complex systems have been conceived without comparison to simpler neural baseline systems that would justify their complexity. In this work, we propose a simple heuristic that guides the development of neural baseline systems for the extractive QA task. We find that there are two ingredients necessary for building a high-performing neural QA system: first, the awareness of question words while processing the context and second, a composition function that goes beyond simple bag-of-words modeling, such as recurrent neural networks. Our results show that FastQA, a system that meets these two requirements, can achieve very competitive performance compared with existing models. We argue that this surprising finding puts results of previous systems and the complexity of recent QA datasets into perspective.
[ { "version": "v1", "created": "Tue, 14 Mar 2017 23:09:45 GMT" }, { "version": "v2", "created": "Fri, 7 Apr 2017 07:40:23 GMT" }, { "version": "v3", "created": "Thu, 8 Jun 2017 14:12:35 GMT" } ]
2017-06-09T00:00:00
[ [ "Weissenborn", "Dirk", "" ], [ "Wiese", "Georg", "" ], [ "Seiffe", "Laura", "" ] ]
TITLE: Making Neural QA as Simple as Possible but not Simpler ABSTRACT: Recent development of large-scale question answering (QA) datasets triggered a substantial amount of research into end-to-end neural architectures for QA. Increasingly complex systems have been conceived without comparison to simpler neural baseline systems that would justify their complexity. In this work, we propose a simple heuristic that guides the development of neural baseline systems for the extractive QA task. We find that there are two ingredients necessary for building a high-performing neural QA system: first, the awareness of question words while processing the context and second, a composition function that goes beyond simple bag-of-words modeling, such as recurrent neural networks. Our results show that FastQA, a system that meets these two requirements, can achieve very competitive performance compared with existing models. We argue that this surprising finding puts results of previous systems and the complexity of recent QA datasets into perspective.
no_new_dataset
0.943556
1703.09507
Rajeev Ranjan
Rajeev Ranjan, Carlos D. Castillo and Rama Chellappa
L2-constrained Softmax Loss for Discriminative Face Verification
null
null
null
null
cs.CV
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
In recent years, the performance of face verification systems has significantly improved using deep convolutional neural networks (DCNNs). A typical pipeline for face verification includes training a deep network for subject classification with softmax loss, using the penultimate layer output as the feature descriptor, and generating a cosine similarity score given a pair of face images. The softmax loss function does not optimize the features to have higher similarity score for positive pairs and lower similarity score for negative pairs, which leads to a performance gap. In this paper, we add an L2-constraint to the feature descriptors which restricts them to lie on a hypersphere of a fixed radius. This module can be easily implemented using existing deep learning frameworks. We show that integrating this simple step in the training pipeline significantly boosts the performance of face verification. Specifically, we achieve state-of-the-art results on the challenging IJB-A dataset, achieving True Accept Rate of 0.909 at False Accept Rate 0.0001 on the face verification protocol. Additionally, we achieve state-of-the-art performance on LFW dataset with an accuracy of 99.78%, and competing performance on YTF dataset with accuracy of 96.08%.
[ { "version": "v1", "created": "Tue, 28 Mar 2017 11:19:50 GMT" }, { "version": "v2", "created": "Mon, 8 May 2017 21:30:51 GMT" }, { "version": "v3", "created": "Wed, 7 Jun 2017 18:58:18 GMT" } ]
2017-06-09T00:00:00
[ [ "Ranjan", "Rajeev", "" ], [ "Castillo", "Carlos D.", "" ], [ "Chellappa", "Rama", "" ] ]
TITLE: L2-constrained Softmax Loss for Discriminative Face Verification ABSTRACT: In recent years, the performance of face verification systems has significantly improved using deep convolutional neural networks (DCNNs). A typical pipeline for face verification includes training a deep network for subject classification with softmax loss, using the penultimate layer output as the feature descriptor, and generating a cosine similarity score given a pair of face images. The softmax loss function does not optimize the features to have higher similarity score for positive pairs and lower similarity score for negative pairs, which leads to a performance gap. In this paper, we add an L2-constraint to the feature descriptors which restricts them to lie on a hypersphere of a fixed radius. This module can be easily implemented using existing deep learning frameworks. We show that integrating this simple step in the training pipeline significantly boosts the performance of face verification. Specifically, we achieve state-of-the-art results on the challenging IJB-A dataset, achieving True Accept Rate of 0.909 at False Accept Rate 0.0001 on the face verification protocol. Additionally, we achieve state-of-the-art performance on LFW dataset with an accuracy of 99.78%, and competing performance on YTF dataset with accuracy of 96.08%.
no_new_dataset
0.949529
1705.03821
Djallel Bouneffouf
Djallel Bouneffouf, Irina Rish, Guillermo A. Cecchi, Raphael Feraud
Context Attentive Bandits: Contextual Bandit with Restricted Context
IJCAI 2017
null
null
null
cs.AI cs.LG stat.ML
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We consider a novel formulation of the multi-armed bandit model, which we call the contextual bandit with restricted context, where only a limited number of features can be accessed by the learner at every iteration. This novel formulation is motivated by different online problems arising in clinical trials, recommender systems and attention modeling. Herein, we adapt the standard multi-armed bandit algorithm known as Thompson Sampling to take advantage of our restricted context setting, and propose two novel algorithms, called the Thompson Sampling with Restricted Context(TSRC) and the Windows Thompson Sampling with Restricted Context(WTSRC), for handling stationary and nonstationary environments, respectively. Our empirical results demonstrate advantages of the proposed approaches on several real-life datasets
[ { "version": "v1", "created": "Wed, 10 May 2017 15:32:36 GMT" }, { "version": "v2", "created": "Wed, 7 Jun 2017 18:40:28 GMT" } ]
2017-06-09T00:00:00
[ [ "Bouneffouf", "Djallel", "" ], [ "Rish", "Irina", "" ], [ "Cecchi", "Guillermo A.", "" ], [ "Feraud", "Raphael", "" ] ]
TITLE: Context Attentive Bandits: Contextual Bandit with Restricted Context ABSTRACT: We consider a novel formulation of the multi-armed bandit model, which we call the contextual bandit with restricted context, where only a limited number of features can be accessed by the learner at every iteration. This novel formulation is motivated by different online problems arising in clinical trials, recommender systems and attention modeling. Herein, we adapt the standard multi-armed bandit algorithm known as Thompson Sampling to take advantage of our restricted context setting, and propose two novel algorithms, called the Thompson Sampling with Restricted Context(TSRC) and the Windows Thompson Sampling with Restricted Context(WTSRC), for handling stationary and nonstationary environments, respectively. Our empirical results demonstrate advantages of the proposed approaches on several real-life datasets
no_new_dataset
0.952175
1706.02291
Sharath Adavanne
Sharath Adavanne, Pasi Pertil\"a, Tuomas Virtanen
Sound Event Detection Using Spatial Features and Convolutional Recurrent Neural Network
Accepted for IEEE International Conference on Acoustics, Speech and Signal Processing (ICASSP 2017)
null
null
null
cs.SD cs.LG
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
This paper proposes to use low-level spatial features extracted from multichannel audio for sound event detection. We extend the convolutional recurrent neural network to handle more than one type of these multichannel features by learning from each of them separately in the initial stages. We show that instead of concatenating the features of each channel into a single feature vector the network learns sound events in multichannel audio better when they are presented as separate layers of a volume. Using the proposed spatial features over monaural features on the same network gives an absolute F-score improvement of 6.1% on the publicly available TUT-SED 2016 dataset and 2.7% on the TUT-SED 2009 dataset that is fifteen times larger.
[ { "version": "v1", "created": "Wed, 7 Jun 2017 06:01:48 GMT" } ]
2017-06-09T00:00:00
[ [ "Adavanne", "Sharath", "" ], [ "Pertilä", "Pasi", "" ], [ "Virtanen", "Tuomas", "" ] ]
TITLE: Sound Event Detection Using Spatial Features and Convolutional Recurrent Neural Network ABSTRACT: This paper proposes to use low-level spatial features extracted from multichannel audio for sound event detection. We extend the convolutional recurrent neural network to handle more than one type of these multichannel features by learning from each of them separately in the initial stages. We show that instead of concatenating the features of each channel into a single feature vector the network learns sound events in multichannel audio better when they are presented as separate layers of a volume. Using the proposed spatial features over monaural features on the same network gives an absolute F-score improvement of 6.1% on the publicly available TUT-SED 2016 dataset and 2.7% on the TUT-SED 2009 dataset that is fifteen times larger.
no_new_dataset
0.954647
1706.02292
Sharath Adavanne
Miroslav Malik, Sharath Adavanne, Konstantinos Drossos, Tuomas Virtanen, Dasa Ticha, Roman Jarina
Stacked Convolutional and Recurrent Neural Networks for Music Emotion Recognition
Accepted for Sound and Music Computing (SMC 2017)
null
null
null
cs.SD cs.LG
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
This paper studies the emotion recognition from musical tracks in the 2-dimensional valence-arousal (V-A) emotional space. We propose a method based on convolutional (CNN) and recurrent neural networks (RNN), having significantly fewer parameters compared with the state-of-the-art method for the same task. We utilize one CNN layer followed by two branches of RNNs trained separately for arousal and valence. The method was evaluated using the 'MediaEval2015 emotion in music' dataset. We achieved an RMSE of 0.202 for arousal and 0.268 for valence, which is the best result reported on this dataset.
[ { "version": "v1", "created": "Wed, 7 Jun 2017 06:06:14 GMT" } ]
2017-06-09T00:00:00
[ [ "Malik", "Miroslav", "" ], [ "Adavanne", "Sharath", "" ], [ "Drossos", "Konstantinos", "" ], [ "Virtanen", "Tuomas", "" ], [ "Ticha", "Dasa", "" ], [ "Jarina", "Roman", "" ] ]
TITLE: Stacked Convolutional and Recurrent Neural Networks for Music Emotion Recognition ABSTRACT: This paper studies the emotion recognition from musical tracks in the 2-dimensional valence-arousal (V-A) emotional space. We propose a method based on convolutional (CNN) and recurrent neural networks (RNN), having significantly fewer parameters compared with the state-of-the-art method for the same task. We utilize one CNN layer followed by two branches of RNNs trained separately for arousal and valence. The method was evaluated using the 'MediaEval2015 emotion in music' dataset. We achieved an RMSE of 0.202 for arousal and 0.268 for valence, which is the best result reported on this dataset.
no_new_dataset
0.950411
1706.02387
Jorge Blasco
Jorge Blasco, Thomas M. Chen, Igor Muttik and Markus Roggenbach
Detection of App Collusion Potential Using Logic Programming
null
null
null
null
cs.CR
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Android is designed with a number of built-in security features such as app sandboxing and permission-based access controls. Android supports multiple communication methods for apps to cooperate. This creates a security risk of app collusion. For instance, a sandboxed app with permission to access sensitive data might leak that data to another sandboxed app with access to the internet. In this paper, we present a method to detect potential collusion between apps. First, we extract from apps all information about their accesses to protected resources and communications. Then we identify sets of apps that might be colluding by using rules in first order logic codified in Prolog. After these, more computationally demanding approaches like taint analysis can focus on the identified sets that show collusion potential. This "filtering" approach is validated against a dataset of manually crafted colluding apps. We also demonstrate that our tool scales by running it on a set of more than 50,000 apps collected in the wild. Our tool allowed us to detect a large set of real apps that used collusion as a synchronization method to maximize the effects of a payload that was injected into all of them via the same SDK.
[ { "version": "v1", "created": "Wed, 7 Jun 2017 21:36:41 GMT" } ]
2017-06-09T00:00:00
[ [ "Blasco", "Jorge", "" ], [ "Chen", "Thomas M.", "" ], [ "Muttik", "Igor", "" ], [ "Roggenbach", "Markus", "" ] ]
TITLE: Detection of App Collusion Potential Using Logic Programming ABSTRACT: Android is designed with a number of built-in security features such as app sandboxing and permission-based access controls. Android supports multiple communication methods for apps to cooperate. This creates a security risk of app collusion. For instance, a sandboxed app with permission to access sensitive data might leak that data to another sandboxed app with access to the internet. In this paper, we present a method to detect potential collusion between apps. First, we extract from apps all information about their accesses to protected resources and communications. Then we identify sets of apps that might be colluding by using rules in first order logic codified in Prolog. After these, more computationally demanding approaches like taint analysis can focus on the identified sets that show collusion potential. This "filtering" approach is validated against a dataset of manually crafted colluding apps. We also demonstrate that our tool scales by running it on a set of more than 50,000 apps collected in the wild. Our tool allowed us to detect a large set of real apps that used collusion as a synchronization method to maximize the effects of a payload that was injected into all of them via the same SDK.
new_dataset
0.878314
1706.02409
Shahin Jabbari
Richard Berk, Hoda Heidari, Shahin Jabbari, Matthew Joseph, Michael Kearns, Jamie Morgenstern, Seth Neel, Aaron Roth
A Convex Framework for Fair Regression
null
null
null
null
cs.LG stat.ML
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We introduce a flexible family of fairness regularizers for (linear and logistic) regression problems. These regularizers all enjoy convexity, permitting fast optimization, and they span the rang from notions of group fairness to strong individual fairness. By varying the weight on the fairness regularizer, we can compute the efficient frontier of the accuracy-fairness trade-off on any given dataset, and we measure the severity of this trade-off via a numerical quantity we call the Price of Fairness (PoF). The centerpiece of our results is an extensive comparative study of the PoF across six different datasets in which fairness is a primary consideration.
[ { "version": "v1", "created": "Wed, 7 Jun 2017 23:09:28 GMT" } ]
2017-06-09T00:00:00
[ [ "Berk", "Richard", "" ], [ "Heidari", "Hoda", "" ], [ "Jabbari", "Shahin", "" ], [ "Joseph", "Matthew", "" ], [ "Kearns", "Michael", "" ], [ "Morgenstern", "Jamie", "" ], [ "Neel", "Seth", "" ], [ "Roth", "Aaron", "" ] ]
TITLE: A Convex Framework for Fair Regression ABSTRACT: We introduce a flexible family of fairness regularizers for (linear and logistic) regression problems. These regularizers all enjoy convexity, permitting fast optimization, and they span the rang from notions of group fairness to strong individual fairness. By varying the weight on the fairness regularizer, we can compute the efficient frontier of the accuracy-fairness trade-off on any given dataset, and we measure the severity of this trade-off via a numerical quantity we call the Price of Fairness (PoF). The centerpiece of our results is an extensive comparative study of the PoF across six different datasets in which fairness is a primary consideration.
no_new_dataset
0.949809
1706.02427
Duyu Tang
Zhao Yan and Duyu Tang and Nan Duan and Junwei Bao and Yuanhua Lv and Ming Zhou and Zhoujun Li
Content-Based Table Retrieval for Web Queries
null
null
null
null
cs.CL
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Understanding the connections between unstructured text and semi-structured table is an important yet neglected problem in natural language processing. In this work, we focus on content-based table retrieval. Given a query, the task is to find the most relevant table from a collection of tables. Further progress towards improving this area requires powerful models of semantic matching and richer training and evaluation resources. To remedy this, we present a ranking based approach, and implement both carefully designed features and neural network architectures to measure the relevance between a query and the content of a table. Furthermore, we release an open-domain dataset that includes 21,113 web queries for 273,816 tables. We conduct comprehensive experiments on both real world and synthetic datasets. Results verify the effectiveness of our approach and present the challenges for this task.
[ { "version": "v1", "created": "Thu, 8 Jun 2017 02:03:32 GMT" } ]
2017-06-09T00:00:00
[ [ "Yan", "Zhao", "" ], [ "Tang", "Duyu", "" ], [ "Duan", "Nan", "" ], [ "Bao", "Junwei", "" ], [ "Lv", "Yuanhua", "" ], [ "Zhou", "Ming", "" ], [ "Li", "Zhoujun", "" ] ]
TITLE: Content-Based Table Retrieval for Web Queries ABSTRACT: Understanding the connections between unstructured text and semi-structured table is an important yet neglected problem in natural language processing. In this work, we focus on content-based table retrieval. Given a query, the task is to find the most relevant table from a collection of tables. Further progress towards improving this area requires powerful models of semantic matching and richer training and evaluation resources. To remedy this, we present a ranking based approach, and implement both carefully designed features and neural network architectures to measure the relevance between a query and the content of a table. Furthermore, we release an open-domain dataset that includes 21,113 web queries for 273,816 tables. We conduct comprehensive experiments on both real world and synthetic datasets. Results verify the effectiveness of our approach and present the challenges for this task.
new_dataset
0.959116
1706.02430
Zhongliang Yang
Zhongliang Yang, Yu-Jin Zhang, Sadaqat ur Rehman, Yongfeng Huang
Image Captioning with Object Detection and Localization
null
null
null
null
cs.CV
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Automatically generating a natural language description of an image is a task close to the heart of image understanding. In this paper, we present a multi-model neural network method closely related to the human visual system that automatically learns to describe the content of images. Our model consists of two sub-models: an object detection and localization model, which extract the information of objects and their spatial relationship in images respectively; Besides, a deep recurrent neural network (RNN) based on long short-term memory (LSTM) units with attention mechanism for sentences generation. Each word of the description will be automatically aligned to different objects of the input image when it is generated. This is similar to the attention mechanism of the human visual system. Experimental results on the COCO dataset showcase the merit of the proposed method, which outperforms previous benchmark models.
[ { "version": "v1", "created": "Thu, 8 Jun 2017 02:23:33 GMT" } ]
2017-06-09T00:00:00
[ [ "Yang", "Zhongliang", "" ], [ "Zhang", "Yu-Jin", "" ], [ "Rehman", "Sadaqat ur", "" ], [ "Huang", "Yongfeng", "" ] ]
TITLE: Image Captioning with Object Detection and Localization ABSTRACT: Automatically generating a natural language description of an image is a task close to the heart of image understanding. In this paper, we present a multi-model neural network method closely related to the human visual system that automatically learns to describe the content of images. Our model consists of two sub-models: an object detection and localization model, which extract the information of objects and their spatial relationship in images respectively; Besides, a deep recurrent neural network (RNN) based on long short-term memory (LSTM) units with attention mechanism for sentences generation. Each word of the description will be automatically aligned to different objects of the input image when it is generated. This is similar to the attention mechanism of the human visual system. Experimental results on the COCO dataset showcase the merit of the proposed method, which outperforms previous benchmark models.
no_new_dataset
0.948728
1706.02434
D\'ario Oliveira
Dario Augusto Borges Oliveira, Laura Leal-Taixe, Raul Queiroz Feitosa, Bodo Rosenhahn
Automatic tracking of vessel-like structures from a single starting point
null
null
10.1016/j.compmedimag.2015.11.002
null
cs.CV
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The identification of vascular networks is an important topic in the medical image analysis community. While most methods focus on single vessel tracking, the few solutions that exist for tracking complete vascular networks are usually computationally intensive and require a lot of user interaction. In this paper we present a method to track full vascular networks iteratively using a single starting point. Our approach is based on a cloud of sampling points distributed over concentric spherical layers. We also proposed a vessel model and a metric of how well a sample point fits this model. Then, we implement the network tracking as a min-cost flow problem, and propose a novel optimization scheme to iteratively track the vessel structure by inherently handling bifurcations and paths. The method was tested using both synthetic and real images. On the 9 different data-sets of synthetic blood vessels, we achieved maximum accuracies of more than 98\%. We further use the synthetic data-set to analyse the sensibility of our method to parameter setting, showing the robustness of the proposed algorithm. For real images, we used coronary, carotid and pulmonary data to segment vascular structures and present the visual results. Still for real images, we present numerical and visual results for networks of nerve fibers in the olfactory system. Further visual results also show the potential of our approach for identifying vascular networks topologies. The presented method delivers good results for the several different datasets tested and have potential for segmenting vessel-like structures. Also, the topology information, inherently extracted, can be used for further analysis to computed aided diagnosis and surgical planning. Finally, the method's modular aspect holds potential for problem-oriented adjustments and improvements.
[ { "version": "v1", "created": "Thu, 8 Jun 2017 02:45:27 GMT" } ]
2017-06-09T00:00:00
[ [ "Oliveira", "Dario Augusto Borges", "" ], [ "Leal-Taixe", "Laura", "" ], [ "Feitosa", "Raul Queiroz", "" ], [ "Rosenhahn", "Bodo", "" ] ]
TITLE: Automatic tracking of vessel-like structures from a single starting point ABSTRACT: The identification of vascular networks is an important topic in the medical image analysis community. While most methods focus on single vessel tracking, the few solutions that exist for tracking complete vascular networks are usually computationally intensive and require a lot of user interaction. In this paper we present a method to track full vascular networks iteratively using a single starting point. Our approach is based on a cloud of sampling points distributed over concentric spherical layers. We also proposed a vessel model and a metric of how well a sample point fits this model. Then, we implement the network tracking as a min-cost flow problem, and propose a novel optimization scheme to iteratively track the vessel structure by inherently handling bifurcations and paths. The method was tested using both synthetic and real images. On the 9 different data-sets of synthetic blood vessels, we achieved maximum accuracies of more than 98\%. We further use the synthetic data-set to analyse the sensibility of our method to parameter setting, showing the robustness of the proposed algorithm. For real images, we used coronary, carotid and pulmonary data to segment vascular structures and present the visual results. Still for real images, we present numerical and visual results for networks of nerve fibers in the olfactory system. Further visual results also show the potential of our approach for identifying vascular networks topologies. The presented method delivers good results for the several different datasets tested and have potential for segmenting vessel-like structures. Also, the topology information, inherently extracted, can be used for further analysis to computed aided diagnosis and surgical planning. Finally, the method's modular aspect holds potential for problem-oriented adjustments and improvements.
no_new_dataset
0.949295
1706.02480
Jeffrey Humpherys
Chris Hettinger, Tanner Christensen, Ben Ehlert, Jeffrey Humpherys, Tyler Jarvis, and Sean Wade
Forward Thinking: Building and Training Neural Networks One Layer at a Time
null
null
null
null
stat.ML cs.LG
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We present a general framework for training deep neural networks without backpropagation. This substantially decreases training time and also allows for construction of deep networks with many sorts of learners, including networks whose layers are defined by functions that are not easily differentiated, like decision trees. The main idea is that layers can be trained one at a time, and once they are trained, the input data are mapped forward through the layer to create a new learning problem. The process is repeated, transforming the data through multiple layers, one at a time, rendering a new data set, which is expected to be better behaved, and on which a final output layer can achieve good performance. We call this forward thinking and demonstrate a proof of concept by achieving state-of-the-art accuracy on the MNIST dataset for convolutional neural networks. We also provide a general mathematical formulation of forward thinking that allows for other types of deep learning problems to be considered.
[ { "version": "v1", "created": "Thu, 8 Jun 2017 08:53:00 GMT" } ]
2017-06-09T00:00:00
[ [ "Hettinger", "Chris", "" ], [ "Christensen", "Tanner", "" ], [ "Ehlert", "Ben", "" ], [ "Humpherys", "Jeffrey", "" ], [ "Jarvis", "Tyler", "" ], [ "Wade", "Sean", "" ] ]
TITLE: Forward Thinking: Building and Training Neural Networks One Layer at a Time ABSTRACT: We present a general framework for training deep neural networks without backpropagation. This substantially decreases training time and also allows for construction of deep networks with many sorts of learners, including networks whose layers are defined by functions that are not easily differentiated, like decision trees. The main idea is that layers can be trained one at a time, and once they are trained, the input data are mapped forward through the layer to create a new learning problem. The process is repeated, transforming the data through multiple layers, one at a time, rendering a new data set, which is expected to be better behaved, and on which a final output layer can achieve good performance. We call this forward thinking and demonstrate a proof of concept by achieving state-of-the-art accuracy on the MNIST dataset for convolutional neural networks. We also provide a general mathematical formulation of forward thinking that allows for other types of deep learning problems to be considered.
no_new_dataset
0.952353
1001.1027
Jascha Sohl-Dickstein
Jascha Sohl-Dickstein, Ching Ming Wang, Bruno A. Olshausen
An Unsupervised Algorithm For Learning Lie Group Transformations
null
null
null
null
cs.CV cs.LG
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We present several theoretical contributions which allow Lie groups to be fit to high dimensional datasets. Transformation operators are represented in their eigen-basis, reducing the computational complexity of parameter estimation to that of training a linear transformation model. A transformation specific "blurring" operator is introduced that allows inference to escape local minima via a smoothing of the transformation space. A penalty on traversed manifold distance is added which encourages the discovery of sparse, minimal distance, transformations between states. Both learning and inference are demonstrated using these methods for the full set of affine transformations on natural image patches. Transformation operators are then trained on natural video sequences. It is shown that the learned video transformations provide a better description of inter-frame differences than the standard motion model based on rigid translation.
[ { "version": "v1", "created": "Thu, 7 Jan 2010 06:22:56 GMT" }, { "version": "v2", "created": "Mon, 18 Jan 2010 07:18:39 GMT" }, { "version": "v3", "created": "Wed, 30 Nov 2011 04:35:48 GMT" }, { "version": "v4", "created": "Thu, 24 Jul 2014 23:34:43 GMT" }, { "version": "v5", "created": "Wed, 7 Jun 2017 17:05:16 GMT" } ]
2017-06-08T00:00:00
[ [ "Sohl-Dickstein", "Jascha", "" ], [ "Wang", "Ching Ming", "" ], [ "Olshausen", "Bruno A.", "" ] ]
TITLE: An Unsupervised Algorithm For Learning Lie Group Transformations ABSTRACT: We present several theoretical contributions which allow Lie groups to be fit to high dimensional datasets. Transformation operators are represented in their eigen-basis, reducing the computational complexity of parameter estimation to that of training a linear transformation model. A transformation specific "blurring" operator is introduced that allows inference to escape local minima via a smoothing of the transformation space. A penalty on traversed manifold distance is added which encourages the discovery of sparse, minimal distance, transformations between states. Both learning and inference are demonstrated using these methods for the full set of affine transformations on natural image patches. Transformation operators are then trained on natural video sequences. It is shown that the learned video transformations provide a better description of inter-frame differences than the standard motion model based on rigid translation.
no_new_dataset
0.946399
1705.08106
Juanhui Tu
Hong Liu and Juanhui Tu and Mengyuan Liu
Two-Stream 3D Convolutional Neural Network for Skeleton-Based Action Recognition
5 pages, 6 figures, 3 tabels
null
null
null
cs.CV
http://creativecommons.org/licenses/by/4.0/
It remains a challenge to efficiently extract spatialtemporal information from skeleton sequences for 3D human action recognition. Although most recent action recognition methods are based on Recurrent Neural Networks which present outstanding performance, one of the shortcomings of these methods is the tendency to overemphasize the temporal information. Since 3D convolutional neural network(3D CNN) is a powerful tool to simultaneously learn features from both spatial and temporal dimensions through capturing the correlations between three dimensional signals, this paper proposes a novel two-stream model using 3D CNN. To our best knowledge, this is the first application of 3D CNN in skeleton-based action recognition. Our method consists of three stages. First, skeleton joints are mapped into a 3D coordinate space and then encoding the spatial and temporal information, respectively. Second, 3D CNN models are seperately adopted to extract deep features from two streams. Third, to enhance the ability of deep features to capture global relationships, we extend every stream into multitemporal version. Extensive experiments on the SmartHome dataset and the large-scale NTU RGB-D dataset demonstrate that our method outperforms most of RNN-based methods, which verify the complementary property between spatial and temporal information and the robustness to noise.
[ { "version": "v1", "created": "Tue, 23 May 2017 07:36:51 GMT" }, { "version": "v2", "created": "Wed, 7 Jun 2017 11:23:40 GMT" } ]
2017-06-08T00:00:00
[ [ "Liu", "Hong", "" ], [ "Tu", "Juanhui", "" ], [ "Liu", "Mengyuan", "" ] ]
TITLE: Two-Stream 3D Convolutional Neural Network for Skeleton-Based Action Recognition ABSTRACT: It remains a challenge to efficiently extract spatialtemporal information from skeleton sequences for 3D human action recognition. Although most recent action recognition methods are based on Recurrent Neural Networks which present outstanding performance, one of the shortcomings of these methods is the tendency to overemphasize the temporal information. Since 3D convolutional neural network(3D CNN) is a powerful tool to simultaneously learn features from both spatial and temporal dimensions through capturing the correlations between three dimensional signals, this paper proposes a novel two-stream model using 3D CNN. To our best knowledge, this is the first application of 3D CNN in skeleton-based action recognition. Our method consists of three stages. First, skeleton joints are mapped into a 3D coordinate space and then encoding the spatial and temporal information, respectively. Second, 3D CNN models are seperately adopted to extract deep features from two streams. Third, to enhance the ability of deep features to capture global relationships, we extend every stream into multitemporal version. Extensive experiments on the SmartHome dataset and the large-scale NTU RGB-D dataset demonstrate that our method outperforms most of RNN-based methods, which verify the complementary property between spatial and temporal information and the robustness to noise.
no_new_dataset
0.946399
1705.08940
Quentin Bateux
Quentin Bateux, Eric Marchand, J\"urgen Leitner, Francois Chaumette, Peter Corke
Visual Servoing from Deep Neural Networks
fixed authors list
null
null
null
cs.RO cs.CV
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We present a deep neural network-based method to perform high-precision, robust and real-time 6 DOF visual servoing. The paper describes how to create a dataset simulating various perturbations (occlusions and lighting conditions) from a single real-world image of the scene. A convolutional neural network is fine-tuned using this dataset to estimate the relative pose between two images of the same scene. The output of the network is then employed in a visual servoing control scheme. The method converges robustly even in difficult real-world settings with strong lighting variations and occlusions.A positioning error of less than one millimeter is obtained in experiments with a 6 DOF robot.
[ { "version": "v1", "created": "Wed, 24 May 2017 19:39:25 GMT" }, { "version": "v2", "created": "Wed, 7 Jun 2017 09:26:34 GMT" } ]
2017-06-08T00:00:00
[ [ "Bateux", "Quentin", "" ], [ "Marchand", "Eric", "" ], [ "Leitner", "Jürgen", "" ], [ "Chaumette", "Francois", "" ], [ "Corke", "Peter", "" ] ]
TITLE: Visual Servoing from Deep Neural Networks ABSTRACT: We present a deep neural network-based method to perform high-precision, robust and real-time 6 DOF visual servoing. The paper describes how to create a dataset simulating various perturbations (occlusions and lighting conditions) from a single real-world image of the scene. A convolutional neural network is fine-tuned using this dataset to estimate the relative pose between two images of the same scene. The output of the network is then employed in a visual servoing control scheme. The method converges robustly even in difficult real-world settings with strong lighting variations and occlusions.A positioning error of less than one millimeter is obtained in experiments with a 6 DOF robot.
no_new_dataset
0.562436
1706.01556
Yifan Peng
Yifan Peng and Zhiyong Lu
Deep learning for extracting protein-protein interactions from biomedical literature
Accepted for publication in Proceedings of the 2017 Workshop on Biomedical Natural Language Processing, 10 pages, 2 figures, 6 tables
null
null
null
cs.CL cs.LG q-bio.QM
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
State-of-the-art methods for protein-protein interaction (PPI) extraction are primarily feature-based or kernel-based by leveraging lexical and syntactic information. But how to incorporate such knowledge in the recent deep learning methods remains an open question. In this paper, we propose a multichannel dependency-based convolutional neural network model (McDepCNN). It applies one channel to the embedding vector of each word in the sentence, and another channel to the embedding vector of the head of the corresponding word. Therefore, the model can use richer information obtained from different channels. Experiments on two public benchmarking datasets, AIMed and BioInfer, demonstrate that McDepCNN compares favorably to the state-of-the-art rich-feature and single-kernel based methods. In addition, McDepCNN achieves 24.4% relative improvement in F1-score over the state-of-the-art methods on cross-corpus evaluation and 12% improvement in F1-score over kernel-based methods on "difficult" instances. These results suggest that McDepCNN generalizes more easily over different corpora, and is capable of capturing long distance features in the sentences.
[ { "version": "v1", "created": "Mon, 5 Jun 2017 23:09:06 GMT" }, { "version": "v2", "created": "Wed, 7 Jun 2017 00:28:21 GMT" } ]
2017-06-08T00:00:00
[ [ "Peng", "Yifan", "" ], [ "Lu", "Zhiyong", "" ] ]
TITLE: Deep learning for extracting protein-protein interactions from biomedical literature ABSTRACT: State-of-the-art methods for protein-protein interaction (PPI) extraction are primarily feature-based or kernel-based by leveraging lexical and syntactic information. But how to incorporate such knowledge in the recent deep learning methods remains an open question. In this paper, we propose a multichannel dependency-based convolutional neural network model (McDepCNN). It applies one channel to the embedding vector of each word in the sentence, and another channel to the embedding vector of the head of the corresponding word. Therefore, the model can use richer information obtained from different channels. Experiments on two public benchmarking datasets, AIMed and BioInfer, demonstrate that McDepCNN compares favorably to the state-of-the-art rich-feature and single-kernel based methods. In addition, McDepCNN achieves 24.4% relative improvement in F1-score over the state-of-the-art methods on cross-corpus evaluation and 12% improvement in F1-score over kernel-based methods on "difficult" instances. These results suggest that McDepCNN generalizes more easily over different corpora, and is capable of capturing long distance features in the sentences.
no_new_dataset
0.952309