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1604.03336
Raef Bassily
Raef Bassily and Yoav Freund
Typical Stability
New sections, extended discussions, and complete proofs
null
null
null
cs.LG cs.DS
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
In this paper, we introduce a notion of algorithmic stability called typical stability. When our goal is to release real-valued queries (statistics) computed over a dataset, this notion does not require the queries to be of bounded sensitivity -- a condition that is generally assumed under differential privacy [DMNS06, Dwork06] when used as a notion of algorithmic stability [DFHPRR15a, DFHPRR15b, BNSSSU16] -- nor does it require the samples in the dataset to be independent -- a condition that is usually assumed when generalization-error guarantees are sought. Instead, typical stability requires the output of the query, when computed on a dataset drawn from the underlying distribution, to be concentrated around its expected value with respect to that distribution. We discuss the implications of typical stability on the generalization error (i.e., the difference between the value of the query computed on the dataset and the expected value of the query with respect to the true data distribution). We show that typical stability can control generalization error in adaptive data analysis even when the samples in the dataset are not necessarily independent and when queries to be computed are not necessarily of bounded-sensitivity as long as the results of the queries over the dataset (i.e., the computed statistics) follow a distribution with a "light" tail. Examples of such queries include, but not limited to, subgaussian and subexponential queries. We also discuss the composition guarantees of typical stability and prove composition theorems that characterize the degradation of the parameters of typical stability under $k$-fold adaptive composition. We also give simple noise-addition algorithms that achieve this notion. These algorithms are similar to their differentially private counterparts, however, the added noise is calibrated differently.
[ { "version": "v1", "created": "Tue, 12 Apr 2016 10:52:06 GMT" }, { "version": "v2", "created": "Mon, 19 Sep 2016 00:06:06 GMT" } ]
2016-09-20T00:00:00
[ [ "Bassily", "Raef", "" ], [ "Freund", "Yoav", "" ] ]
TITLE: Typical Stability ABSTRACT: In this paper, we introduce a notion of algorithmic stability called typical stability. When our goal is to release real-valued queries (statistics) computed over a dataset, this notion does not require the queries to be of bounded sensitivity -- a condition that is generally assumed under differential privacy [DMNS06, Dwork06] when used as a notion of algorithmic stability [DFHPRR15a, DFHPRR15b, BNSSSU16] -- nor does it require the samples in the dataset to be independent -- a condition that is usually assumed when generalization-error guarantees are sought. Instead, typical stability requires the output of the query, when computed on a dataset drawn from the underlying distribution, to be concentrated around its expected value with respect to that distribution. We discuss the implications of typical stability on the generalization error (i.e., the difference between the value of the query computed on the dataset and the expected value of the query with respect to the true data distribution). We show that typical stability can control generalization error in adaptive data analysis even when the samples in the dataset are not necessarily independent and when queries to be computed are not necessarily of bounded-sensitivity as long as the results of the queries over the dataset (i.e., the computed statistics) follow a distribution with a "light" tail. Examples of such queries include, but not limited to, subgaussian and subexponential queries. We also discuss the composition guarantees of typical stability and prove composition theorems that characterize the degradation of the parameters of typical stability under $k$-fold adaptive composition. We also give simple noise-addition algorithms that achieve this notion. These algorithms are similar to their differentially private counterparts, however, the added noise is calibrated differently.
no_new_dataset
0.934694
1605.05411
Ethan Rudd
Andras Rozsa, Manuel G\"unther, Ethan M. Rudd, and Terrance E. Boult
Are Facial Attributes Adversarially Robust?
Pre-print of article accepted to the International Conference on Pattern Recognition (ICPR) 2016. 7 pages total
null
null
null
cs.CV
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Facial attributes are emerging soft biometrics that have the potential to reject non-matches, for example, based on mismatching gender. To be usable in stand-alone systems, facial attributes must be extracted from images automatically and reliably. In this paper, we propose a simple yet effective solution for automatic facial attribute extraction by training a deep convolutional neural network (DCNN) for each facial attribute separately, without using any pre-training or dataset augmentation, and we obtain new state-of-the-art facial attribute classification results on the CelebA benchmark. To test the stability of the networks, we generated adversarial images -- formed by adding imperceptible non-random perturbations to original inputs which result in classification errors -- via a novel fast flipping attribute (FFA) technique. We show that FFA generates more adversarial examples than other related algorithms, and that DCNNs for certain attributes are generally robust to adversarial inputs, while DCNNs for other attributes are not. This result is surprising because no DCNNs tested to date have exhibited robustness to adversarial images without explicit augmentation in the training procedure to account for adversarial examples. Finally, we introduce the concept of natural adversarial samples, i.e., images that are misclassified but can be easily turned into correctly classified images by applying small perturbations. We demonstrate that natural adversarial samples commonly occur, even within the training set, and show that many of these images remain misclassified even with additional training epochs. This phenomenon is surprising because correcting the misclassification, particularly when guided by training data, should require only a small adjustment to the DCNN parameters.
[ { "version": "v1", "created": "Wed, 18 May 2016 01:13:09 GMT" }, { "version": "v2", "created": "Wed, 14 Sep 2016 18:44:50 GMT" }, { "version": "v3", "created": "Fri, 16 Sep 2016 21:49:14 GMT" } ]
2016-09-20T00:00:00
[ [ "Rozsa", "Andras", "" ], [ "Günther", "Manuel", "" ], [ "Rudd", "Ethan M.", "" ], [ "Boult", "Terrance E.", "" ] ]
TITLE: Are Facial Attributes Adversarially Robust? ABSTRACT: Facial attributes are emerging soft biometrics that have the potential to reject non-matches, for example, based on mismatching gender. To be usable in stand-alone systems, facial attributes must be extracted from images automatically and reliably. In this paper, we propose a simple yet effective solution for automatic facial attribute extraction by training a deep convolutional neural network (DCNN) for each facial attribute separately, without using any pre-training or dataset augmentation, and we obtain new state-of-the-art facial attribute classification results on the CelebA benchmark. To test the stability of the networks, we generated adversarial images -- formed by adding imperceptible non-random perturbations to original inputs which result in classification errors -- via a novel fast flipping attribute (FFA) technique. We show that FFA generates more adversarial examples than other related algorithms, and that DCNNs for certain attributes are generally robust to adversarial inputs, while DCNNs for other attributes are not. This result is surprising because no DCNNs tested to date have exhibited robustness to adversarial images without explicit augmentation in the training procedure to account for adversarial examples. Finally, we introduce the concept of natural adversarial samples, i.e., images that are misclassified but can be easily turned into correctly classified images by applying small perturbations. We demonstrate that natural adversarial samples commonly occur, even within the training set, and show that many of these images remain misclassified even with additional training epochs. This phenomenon is surprising because correcting the misclassification, particularly when guided by training data, should require only a small adjustment to the DCNN parameters.
no_new_dataset
0.94625
1608.02158
Adler Perotte
Rajesh Ranganath and Adler Perotte and No\'emie Elhadad and David Blei
Deep Survival Analysis
Presented at 2016 Machine Learning and Healthcare Conference (MLHC 2016), Los Angeles, CA
null
null
null
stat.ML cs.AI stat.ME
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The electronic health record (EHR) provides an unprecedented opportunity to build actionable tools to support physicians at the point of care. In this paper, we investigate survival analysis in the context of EHR data. We introduce deep survival analysis, a hierarchical generative approach to survival analysis. It departs from previous approaches in two primary ways: (1) all observations, including covariates, are modeled jointly conditioned on a rich latent structure; and (2) the observations are aligned by their failure time, rather than by an arbitrary time zero as in traditional survival analysis. Further, it (3) scalably handles heterogeneous (continuous and discrete) data types that occur in the EHR. We validate deep survival analysis model by stratifying patients according to risk of developing coronary heart disease (CHD). Specifically, we study a dataset of 313,000 patients corresponding to 5.5 million months of observations. When compared to the clinically validated Framingham CHD risk score, deep survival analysis is significantly superior in stratifying patients according to their risk.
[ { "version": "v1", "created": "Sat, 6 Aug 2016 22:18:18 GMT" }, { "version": "v2", "created": "Sun, 18 Sep 2016 14:08:02 GMT" } ]
2016-09-20T00:00:00
[ [ "Ranganath", "Rajesh", "" ], [ "Perotte", "Adler", "" ], [ "Elhadad", "Noémie", "" ], [ "Blei", "David", "" ] ]
TITLE: Deep Survival Analysis ABSTRACT: The electronic health record (EHR) provides an unprecedented opportunity to build actionable tools to support physicians at the point of care. In this paper, we investigate survival analysis in the context of EHR data. We introduce deep survival analysis, a hierarchical generative approach to survival analysis. It departs from previous approaches in two primary ways: (1) all observations, including covariates, are modeled jointly conditioned on a rich latent structure; and (2) the observations are aligned by their failure time, rather than by an arbitrary time zero as in traditional survival analysis. Further, it (3) scalably handles heterogeneous (continuous and discrete) data types that occur in the EHR. We validate deep survival analysis model by stratifying patients according to risk of developing coronary heart disease (CHD). Specifically, we study a dataset of 313,000 patients corresponding to 5.5 million months of observations. When compared to the clinically validated Framingham CHD risk score, deep survival analysis is significantly superior in stratifying patients according to their risk.
no_new_dataset
0.851953
1609.03461
Hossein Ziaei Nafchi
Hossein Ziaei Nafchi, Atena Shahkolaei, Rachid Hedjam, Mohamed Cheriet
MUG: A Parameterless No-Reference JPEG Quality Evaluator Robust to Block Size and Misalignment
5 pages, 4 figures, 3 tables
null
10.1109/LSP.2016.2608865
null
cs.CV
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
In this letter, a very simple no-reference image quality assessment (NR-IQA) model for JPEG compressed images is proposed. The proposed metric called median of unique gradients (MUG) is based on the very simple facts of unique gradient magnitudes of JPEG compressed images. MUG is a parameterless metric and does not need training. Unlike other NR-IQAs, MUG is independent to block size and cropping. A more stable index called MUG+ is also introduced. The experimental results on six benchmark datasets of natural images and a benchmark dataset of synthetic images show that MUG is comparable to the state-of-the-art indices in literature. In addition, its performance remains unchanged for the case of the cropped images in which block boundaries are not known. The MATLAB source code of the proposed metrics is available at https://dl.dropboxusercontent.com/u/74505502/MUG.m and https://dl.dropboxusercontent.com/u/74505502/MUGplus.m.
[ { "version": "v1", "created": "Mon, 12 Sep 2016 16:11:26 GMT" }, { "version": "v2", "created": "Mon, 19 Sep 2016 16:33:48 GMT" } ]
2016-09-20T00:00:00
[ [ "Nafchi", "Hossein Ziaei", "" ], [ "Shahkolaei", "Atena", "" ], [ "Hedjam", "Rachid", "" ], [ "Cheriet", "Mohamed", "" ] ]
TITLE: MUG: A Parameterless No-Reference JPEG Quality Evaluator Robust to Block Size and Misalignment ABSTRACT: In this letter, a very simple no-reference image quality assessment (NR-IQA) model for JPEG compressed images is proposed. The proposed metric called median of unique gradients (MUG) is based on the very simple facts of unique gradient magnitudes of JPEG compressed images. MUG is a parameterless metric and does not need training. Unlike other NR-IQAs, MUG is independent to block size and cropping. A more stable index called MUG+ is also introduced. The experimental results on six benchmark datasets of natural images and a benchmark dataset of synthetic images show that MUG is comparable to the state-of-the-art indices in literature. In addition, its performance remains unchanged for the case of the cropped images in which block boundaries are not known. The MATLAB source code of the proposed metrics is available at https://dl.dropboxusercontent.com/u/74505502/MUG.m and https://dl.dropboxusercontent.com/u/74505502/MUGplus.m.
no_new_dataset
0.949669
1609.05281
Ankit Gandhi
Ankit Gandhi, Arjun Sharma, Arijit Biswas, Om Deshmukh
GeThR-Net: A Generalized Temporally Hybrid Recurrent Neural Network for Multimodal Information Fusion
To appear in ECCV workshop on Computer Vision for Audio-Visual Media, 2016
null
null
null
cs.CV
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Data generated from real world events are usually temporal and contain multimodal information such as audio, visual, depth, sensor etc. which are required to be intelligently combined for classification tasks. In this paper, we propose a novel generalized deep neural network architecture where temporal streams from multiple modalities are combined. There are total M+1 (M is the number of modalities) components in the proposed network. The first component is a novel temporally hybrid Recurrent Neural Network (RNN) that exploits the complimentary nature of the multimodal temporal information by allowing the network to learn both modality specific temporal dynamics as well as the dynamics in a multimodal feature space. M additional components are added to the network which extract discriminative but non-temporal cues from each modality. Finally, the predictions from all of these components are linearly combined using a set of automatically learned weights. We perform exhaustive experiments on three different datasets spanning four modalities. The proposed network is relatively 3.5%, 5.7% and 2% better than the best performing temporal multimodal baseline for UCF-101, CCV and Multimodal Gesture datasets respectively.
[ { "version": "v1", "created": "Sat, 17 Sep 2016 04:18:02 GMT" } ]
2016-09-20T00:00:00
[ [ "Gandhi", "Ankit", "" ], [ "Sharma", "Arjun", "" ], [ "Biswas", "Arijit", "" ], [ "Deshmukh", "Om", "" ] ]
TITLE: GeThR-Net: A Generalized Temporally Hybrid Recurrent Neural Network for Multimodal Information Fusion ABSTRACT: Data generated from real world events are usually temporal and contain multimodal information such as audio, visual, depth, sensor etc. which are required to be intelligently combined for classification tasks. In this paper, we propose a novel generalized deep neural network architecture where temporal streams from multiple modalities are combined. There are total M+1 (M is the number of modalities) components in the proposed network. The first component is a novel temporally hybrid Recurrent Neural Network (RNN) that exploits the complimentary nature of the multimodal temporal information by allowing the network to learn both modality specific temporal dynamics as well as the dynamics in a multimodal feature space. M additional components are added to the network which extract discriminative but non-temporal cues from each modality. Finally, the predictions from all of these components are linearly combined using a set of automatically learned weights. We perform exhaustive experiments on three different datasets spanning four modalities. The proposed network is relatively 3.5%, 5.7% and 2% better than the best performing temporal multimodal baseline for UCF-101, CCV and Multimodal Gesture datasets respectively.
no_new_dataset
0.952618
1609.05317
Xingyi Zhou
Xingyi Zhou, Xiao Sun, Wei Zhang, Shuang Liang, Yichen Wei
Deep Kinematic Pose Regression
ECCV Workshop on Geometry Meets Deep Learning, 2016
null
null
null
cs.CV
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Learning articulated object pose is inherently difficult because the pose is high dimensional but has many structural constraints. Most existing work do not model such constraints and does not guarantee the geometric validity of their pose estimation, therefore requiring a post-processing to recover the correct geometry if desired, which is cumbersome and sub-optimal. In this work, we propose to directly embed a kinematic object model into the deep neutral network learning for general articulated object pose estimation. The kinematic function is defined on the appropriately parameterized object motion variables. It is differentiable and can be used in the gradient descent based optimization in network training. The prior knowledge on the object geometric model is fully exploited and the structure is guaranteed to be valid. We show convincing experiment results on a toy example and the 3D human pose estimation problem. For the latter we achieve state-of-the-art result on Human3.6M dataset.
[ { "version": "v1", "created": "Sat, 17 Sep 2016 11:22:11 GMT" } ]
2016-09-20T00:00:00
[ [ "Zhou", "Xingyi", "" ], [ "Sun", "Xiao", "" ], [ "Zhang", "Wei", "" ], [ "Liang", "Shuang", "" ], [ "Wei", "Yichen", "" ] ]
TITLE: Deep Kinematic Pose Regression ABSTRACT: Learning articulated object pose is inherently difficult because the pose is high dimensional but has many structural constraints. Most existing work do not model such constraints and does not guarantee the geometric validity of their pose estimation, therefore requiring a post-processing to recover the correct geometry if desired, which is cumbersome and sub-optimal. In this work, we propose to directly embed a kinematic object model into the deep neutral network learning for general articulated object pose estimation. The kinematic function is defined on the appropriately parameterized object motion variables. It is differentiable and can be used in the gradient descent based optimization in network training. The prior knowledge on the object geometric model is fully exploited and the structure is guaranteed to be valid. We show convincing experiment results on a toy example and the 3D human pose estimation problem. For the latter we achieve state-of-the-art result on Human3.6M dataset.
no_new_dataset
0.948155
1609.05345
Shicong Liu
Shicong Liu, Junru Shao, Hongtao Lu
Generalized residual vector quantization for large scale data
published on International Conference on Multimedia and Expo 2016
null
null
null
cs.MM cs.IR
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Vector quantization is an essential tool for tasks involving large scale data, for example, large scale similarity search, which is crucial for content-based information retrieval and analysis. In this paper, we propose a novel vector quantization framework that iteratively minimizes quantization error. First, we provide a detailed review on a relevant vector quantization method named \textit{residual vector quantization} (RVQ). Next, we propose \textit{generalized residual vector quantization} (GRVQ) to further improve over RVQ. Many vector quantization methods can be viewed as the special cases of our proposed framework. We evaluate GRVQ on several large scale benchmark datasets for large scale search, classification and object retrieval. We compared GRVQ with existing methods in detail. Extensive experiments demonstrate our GRVQ framework substantially outperforms existing methods in term of quantization accuracy and computation efficiency.
[ { "version": "v1", "created": "Sat, 17 Sep 2016 14:50:06 GMT" } ]
2016-09-20T00:00:00
[ [ "Liu", "Shicong", "" ], [ "Shao", "Junru", "" ], [ "Lu", "Hongtao", "" ] ]
TITLE: Generalized residual vector quantization for large scale data ABSTRACT: Vector quantization is an essential tool for tasks involving large scale data, for example, large scale similarity search, which is crucial for content-based information retrieval and analysis. In this paper, we propose a novel vector quantization framework that iteratively minimizes quantization error. First, we provide a detailed review on a relevant vector quantization method named \textit{residual vector quantization} (RVQ). Next, we propose \textit{generalized residual vector quantization} (GRVQ) to further improve over RVQ. Many vector quantization methods can be viewed as the special cases of our proposed framework. We evaluate GRVQ on several large scale benchmark datasets for large scale search, classification and object retrieval. We compared GRVQ with existing methods in detail. Extensive experiments demonstrate our GRVQ framework substantially outperforms existing methods in term of quantization accuracy and computation efficiency.
no_new_dataset
0.948822
1609.05359
Praveen Rao
Praveen Rao, Anas Katib, Daniel E. Lopez Barron
A Knowledge Ecosystem for the Food, Energy, and Water System
KDD 2016 Workshop on Data Science for Food, Energy and Water, Aug 13-17, 2016, San Francisco, CA
null
null
null
cs.DB
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Food, energy, and water (FEW) are key resources to sustain human life and economic growth. There is an increasing stress on these interconnected resources due to population growth, natural disasters, and human activities. New research is necessary to foster more efficient, more secure, and safer use of FEW resources in the U.S. and globally. In this position paper, we present the idea of a knowledge ecosystem for enabling the semantic data integration of heterogeneous datasets in the FEW system to promote knowledge discovery and superior decision making through semantic reasoning. Rich, diverse datasets published by U.S. federal agencies will be utilized. Our knowledge ecosystem will build on Semantic Web technologies and advances in statistical relational learning to (a) represent, integrate, and harmonize diverse data sources and (b) perform ontology-based reasoning to discover actionable insights from FEW datasets.
[ { "version": "v1", "created": "Sat, 17 Sep 2016 16:27:38 GMT" } ]
2016-09-20T00:00:00
[ [ "Rao", "Praveen", "" ], [ "Katib", "Anas", "" ], [ "Barron", "Daniel E. Lopez", "" ] ]
TITLE: A Knowledge Ecosystem for the Food, Energy, and Water System ABSTRACT: Food, energy, and water (FEW) are key resources to sustain human life and economic growth. There is an increasing stress on these interconnected resources due to population growth, natural disasters, and human activities. New research is necessary to foster more efficient, more secure, and safer use of FEW resources in the U.S. and globally. In this position paper, we present the idea of a knowledge ecosystem for enabling the semantic data integration of heterogeneous datasets in the FEW system to promote knowledge discovery and superior decision making through semantic reasoning. Rich, diverse datasets published by U.S. federal agencies will be utilized. Our knowledge ecosystem will build on Semantic Web technologies and advances in statistical relational learning to (a) represent, integrate, and harmonize diverse data sources and (b) perform ontology-based reasoning to discover actionable insights from FEW datasets.
no_new_dataset
0.952309
1609.05388
Charalampos Tsourakakis
Jaros{\l}aw B{\l}asiok, Charalampos E. Tsourakakis
ADAGIO: Fast Data-aware Near-Isometric Linear Embeddings
ICDM 2016
null
null
null
stat.ML cs.LG
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Many important applications, including signal reconstruction, parameter estimation, and signal processing in a compressed domain, rely on a low-dimensional representation of the dataset that preserves {\em all} pairwise distances between the data points and leverages the inherent geometric structure that is typically present. Recently Hedge, Sankaranarayanan, Yin and Baraniuk \cite{hedge2015} proposed the first data-aware near-isometric linear embedding which achieves the best of both worlds. However, their method NuMax does not scale to large-scale datasets. Our main contribution is a simple, data-aware, near-isometric linear dimensionality reduction method which significantly outperforms a state-of-the-art method \cite{hedge2015} with respect to scalability while achieving high quality near-isometries. Furthermore, our method comes with strong worst-case theoretical guarantees that allow us to guarantee the quality of the obtained near-isometry. We verify experimentally the efficiency of our method on numerous real-world datasets, where we find that our method ($<$10 secs) is more than 3\,000$\times$ faster than the state-of-the-art method \cite{hedge2015} ($>$9 hours) on medium scale datasets with 60\,000 data points in 784 dimensions. Finally, we use our method as a preprocessing step to increase the computational efficiency of a classification application and for speeding up approximate nearest neighbor queries.
[ { "version": "v1", "created": "Sat, 17 Sep 2016 21:01:19 GMT" } ]
2016-09-20T00:00:00
[ [ "Błasiok", "Jarosław", "" ], [ "Tsourakakis", "Charalampos E.", "" ] ]
TITLE: ADAGIO: Fast Data-aware Near-Isometric Linear Embeddings ABSTRACT: Many important applications, including signal reconstruction, parameter estimation, and signal processing in a compressed domain, rely on a low-dimensional representation of the dataset that preserves {\em all} pairwise distances between the data points and leverages the inherent geometric structure that is typically present. Recently Hedge, Sankaranarayanan, Yin and Baraniuk \cite{hedge2015} proposed the first data-aware near-isometric linear embedding which achieves the best of both worlds. However, their method NuMax does not scale to large-scale datasets. Our main contribution is a simple, data-aware, near-isometric linear dimensionality reduction method which significantly outperforms a state-of-the-art method \cite{hedge2015} with respect to scalability while achieving high quality near-isometries. Furthermore, our method comes with strong worst-case theoretical guarantees that allow us to guarantee the quality of the obtained near-isometry. We verify experimentally the efficiency of our method on numerous real-world datasets, where we find that our method ($<$10 secs) is more than 3\,000$\times$ faster than the state-of-the-art method \cite{hedge2015} ($>$9 hours) on medium scale datasets with 60\,000 data points in 784 dimensions. Finally, we use our method as a preprocessing step to increase the computational efficiency of a classification application and for speeding up approximate nearest neighbor queries.
no_new_dataset
0.950088
1609.05396
Martin Simonovsky
Martin Simonovsky, Benjam\'in Guti\'errez-Becker, Diana Mateus, Nassir Navab, Nikos Komodakis
A Deep Metric for Multimodal Registration
Accepted to MICCAI 2016; extended version
null
null
null
cs.CV cs.LG cs.NE
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Multimodal registration is a challenging problem in medical imaging due the high variability of tissue appearance under different imaging modalities. The crucial component here is the choice of the right similarity measure. We make a step towards a general learning-based solution that can be adapted to specific situations and present a metric based on a convolutional neural network. Our network can be trained from scratch even from a few aligned image pairs. The metric is validated on intersubject deformable registration on a dataset different from the one used for training, demonstrating good generalization. In this task, we outperform mutual information by a significant margin.
[ { "version": "v1", "created": "Sat, 17 Sep 2016 21:46:21 GMT" } ]
2016-09-20T00:00:00
[ [ "Simonovsky", "Martin", "" ], [ "Gutiérrez-Becker", "Benjamín", "" ], [ "Mateus", "Diana", "" ], [ "Navab", "Nassir", "" ], [ "Komodakis", "Nikos", "" ] ]
TITLE: A Deep Metric for Multimodal Registration ABSTRACT: Multimodal registration is a challenging problem in medical imaging due the high variability of tissue appearance under different imaging modalities. The crucial component here is the choice of the right similarity measure. We make a step towards a general learning-based solution that can be adapted to specific situations and present a metric based on a convolutional neural network. Our network can be trained from scratch even from a few aligned image pairs. The metric is validated on intersubject deformable registration on a dataset different from the one used for training, demonstrating good generalization. In this task, we outperform mutual information by a significant margin.
no_new_dataset
0.949763
1609.05401
Jose Alberto Garc\'ia Guti\'errez Sr.
Jose A. Garc\'ia Guti\'errez
Applications of Data Mining (DM) in Science and Engineering: State of the art and perspectives
in Spanish
null
null
null
cs.AI cs.DB
http://creativecommons.org/licenses/by-nc-sa/4.0/
The continuous increase in the availability of data of any kind, coupled with the development of networks of high-speed communications, the popularization of cloud computing and the growth of data centers and the emergence of high-performance computing does essential the task to develop techniques that allow more efficient data processing and analyzing of large volumes datasets and extraction of valuable information. In the following pages we will discuss about development of this field in recent decades, and its potential and applicability present in the various branches of scientific research. Also, we try to review briefly the different families of algorithms that are included in data mining research area, its scalability with increasing dimensionality of the input data and how they can be addressed and what behavior different methods in a scenario in which the information is distributed or decentralized processed so as to increment performance optimization in heterogeneous environments.
[ { "version": "v1", "created": "Sat, 17 Sep 2016 22:22:17 GMT" } ]
2016-09-20T00:00:00
[ [ "Gutiérrez", "Jose A. García", "" ] ]
TITLE: Applications of Data Mining (DM) in Science and Engineering: State of the art and perspectives ABSTRACT: The continuous increase in the availability of data of any kind, coupled with the development of networks of high-speed communications, the popularization of cloud computing and the growth of data centers and the emergence of high-performance computing does essential the task to develop techniques that allow more efficient data processing and analyzing of large volumes datasets and extraction of valuable information. In the following pages we will discuss about development of this field in recent decades, and its potential and applicability present in the various branches of scientific research. Also, we try to review briefly the different families of algorithms that are included in data mining research area, its scalability with increasing dimensionality of the input data and how they can be addressed and what behavior different methods in a scenario in which the information is distributed or decentralized processed so as to increment performance optimization in heterogeneous environments.
no_new_dataset
0.948202
1609.05420
Senthil Purushwalkam
Senthil Purushwalkam, Abhinav Gupta
Pose from Action: Unsupervised Learning of Pose Features based on Motion
null
null
null
null
cs.CV
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Human actions are comprised of a sequence of poses. This makes videos of humans a rich and dense source of human poses. We propose an unsupervised method to learn pose features from videos that exploits a signal which is complementary to appearance and can be used as supervision: motion. The key idea is that humans go through poses in a predictable manner while performing actions. Hence, given two poses, it should be possible to model the motion that caused the change between them. We represent each of the poses as a feature in a CNN (Appearance ConvNet) and generate a motion encoding from optical flow maps using a separate CNN (Motion ConvNet). The data for this task is automatically generated allowing us to train without human supervision. We demonstrate the strength of the learned representation by finetuning the trained model for Pose Estimation on the FLIC dataset, for static image action recognition on PASCAL and for action recognition in videos on UCF101 and HMDB51.
[ { "version": "v1", "created": "Sun, 18 Sep 2016 04:18:42 GMT" } ]
2016-09-20T00:00:00
[ [ "Purushwalkam", "Senthil", "" ], [ "Gupta", "Abhinav", "" ] ]
TITLE: Pose from Action: Unsupervised Learning of Pose Features based on Motion ABSTRACT: Human actions are comprised of a sequence of poses. This makes videos of humans a rich and dense source of human poses. We propose an unsupervised method to learn pose features from videos that exploits a signal which is complementary to appearance and can be used as supervision: motion. The key idea is that humans go through poses in a predictable manner while performing actions. Hence, given two poses, it should be possible to model the motion that caused the change between them. We represent each of the poses as a feature in a CNN (Appearance ConvNet) and generate a motion encoding from optical flow maps using a separate CNN (Motion ConvNet). The data for this task is automatically generated allowing us to train without human supervision. We demonstrate the strength of the learned representation by finetuning the trained model for Pose Estimation on the FLIC dataset, for static image action recognition on PASCAL and for action recognition in videos on UCF101 and HMDB51.
no_new_dataset
0.947672
1609.05528
Shebuti Rayana
Shebuti Rayana, Wen Zhong and Leman Akoglu
Sequential Ensemble Learning for Outlier Detection: A Bias-Variance Perspective
11 pages, 8 figures, conference
null
null
null
cs.LG stat.ML
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Ensemble methods for classification and clustering have been effectively used for decades, while ensemble learning for outlier detection has only been studied recently. In this work, we design a new ensemble approach for outlier detection in multi-dimensional point data, which provides improved accuracy by reducing error through both bias and variance. Although classification and outlier detection appear as different problems, their theoretical underpinnings are quite similar in terms of the bias-variance trade-off [1], where outlier detection is considered as a binary classification task with unobserved labels but a similar bias-variance decomposition of error. In this paper, we propose a sequential ensemble approach called CARE that employs a two-phase aggregation of the intermediate results in each iteration to reach the final outcome. Unlike existing outlier ensembles which solely incorporate a parallel framework by aggregating the outcomes of independent base detectors to reduce variance, our ensemble incorporates both the parallel and sequential building blocks to reduce bias as well as variance by ($i$) successively eliminating outliers from the original dataset to build a better data model on which outlierness is estimated (sequentially), and ($ii$) combining the results from individual base detectors and across iterations (parallelly). Through extensive experiments on sixteen real-world datasets mainly from the UCI machine learning repository [2], we show that CARE performs significantly better than or at least similar to the individual baselines. We also compare CARE with the state-of-the-art outlier ensembles where it also provides significant improvement when it is the winner and remains close otherwise.
[ { "version": "v1", "created": "Sun, 18 Sep 2016 18:59:42 GMT" } ]
2016-09-20T00:00:00
[ [ "Rayana", "Shebuti", "" ], [ "Zhong", "Wen", "" ], [ "Akoglu", "Leman", "" ] ]
TITLE: Sequential Ensemble Learning for Outlier Detection: A Bias-Variance Perspective ABSTRACT: Ensemble methods for classification and clustering have been effectively used for decades, while ensemble learning for outlier detection has only been studied recently. In this work, we design a new ensemble approach for outlier detection in multi-dimensional point data, which provides improved accuracy by reducing error through both bias and variance. Although classification and outlier detection appear as different problems, their theoretical underpinnings are quite similar in terms of the bias-variance trade-off [1], where outlier detection is considered as a binary classification task with unobserved labels but a similar bias-variance decomposition of error. In this paper, we propose a sequential ensemble approach called CARE that employs a two-phase aggregation of the intermediate results in each iteration to reach the final outcome. Unlike existing outlier ensembles which solely incorporate a parallel framework by aggregating the outcomes of independent base detectors to reduce variance, our ensemble incorporates both the parallel and sequential building blocks to reduce bias as well as variance by ($i$) successively eliminating outliers from the original dataset to build a better data model on which outlierness is estimated (sequentially), and ($ii$) combining the results from individual base detectors and across iterations (parallelly). Through extensive experiments on sixteen real-world datasets mainly from the UCI machine learning repository [2], we show that CARE performs significantly better than or at least similar to the individual baselines. We also compare CARE with the state-of-the-art outlier ensembles where it also provides significant improvement when it is the winner and remains close otherwise.
no_new_dataset
0.946892
1609.05561
Ricardo Fabbri
Anil Usumezbas and Ricardo Fabbri and Benjamin B. Kimia
From Multiview Image Curves to 3D Drawings
Expanded ECCV 2016 version with tweaked figures and including an overview of the supplementary material available at multiview-3d-drawing.sourceforge.net
Lecture Notes in Computer Science, 9908, pp 70-87, september 2016
10.1007/978-3-319-46493-0_5
null
cs.CV cs.CG cs.GR cs.RO
http://creativecommons.org/licenses/by/4.0/
Reconstructing 3D scenes from multiple views has made impressive strides in recent years, chiefly by correlating isolated feature points, intensity patterns, or curvilinear structures. In the general setting - without controlled acquisition, abundant texture, curves and surfaces following specific models or limiting scene complexity - most methods produce unorganized point clouds, meshes, or voxel representations, with some exceptions producing unorganized clouds of 3D curve fragments. Ideally, many applications require structured representations of curves, surfaces and their spatial relationships. This paper presents a step in this direction by formulating an approach that combines 2D image curves into a collection of 3D curves, with topological connectivity between them represented as a 3D graph. This results in a 3D drawing, which is complementary to surface representations in the same sense as a 3D scaffold complements a tent taut over it. We evaluate our results against truth on synthetic and real datasets.
[ { "version": "v1", "created": "Sun, 18 Sep 2016 22:20:35 GMT" } ]
2016-09-20T00:00:00
[ [ "Usumezbas", "Anil", "" ], [ "Fabbri", "Ricardo", "" ], [ "Kimia", "Benjamin B.", "" ] ]
TITLE: From Multiview Image Curves to 3D Drawings ABSTRACT: Reconstructing 3D scenes from multiple views has made impressive strides in recent years, chiefly by correlating isolated feature points, intensity patterns, or curvilinear structures. In the general setting - without controlled acquisition, abundant texture, curves and surfaces following specific models or limiting scene complexity - most methods produce unorganized point clouds, meshes, or voxel representations, with some exceptions producing unorganized clouds of 3D curve fragments. Ideally, many applications require structured representations of curves, surfaces and their spatial relationships. This paper presents a step in this direction by formulating an approach that combines 2D image curves into a collection of 3D curves, with topological connectivity between them represented as a 3D graph. This results in a 3D drawing, which is complementary to surface representations in the same sense as a 3D scaffold complements a tent taut over it. We evaluate our results against truth on synthetic and real datasets.
no_new_dataset
0.944434
1609.05583
Seyed Ali Amirshahi Seyed Ali Amirshahi
Seyed Ali Amirshahi, Gregor Uwe Hayn-Leichsenring, Joachim Denzler, Christoph Redies
Color: A Crucial Factor for Aesthetic Quality Assessment in a Subjective Dataset of Paintings
This paper was presented at the AIC 2013 Congress
null
null
null
cs.CV
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Computational aesthetics is an emerging field of research which has attracted different research groups in the last few years. In this field, one of the main approaches to evaluate the aesthetic quality of paintings and photographs is a feature-based approach. Among the different features proposed to reach this goal, color plays an import role. In this paper, we introduce a novel dataset that consists of paintings of Western provenance from 36 well-known painters from the 15th to the 20th century. As a first step and to assess this dataset, using a classifier, we investigate the correlation between the subjective scores and two widely used features that are related to color perception and in different aesthetic quality assessment approaches. Results show a classification rate of up to 73% between the color features and the subjective scores.
[ { "version": "v1", "created": "Mon, 19 Sep 2016 02:17:34 GMT" } ]
2016-09-20T00:00:00
[ [ "Amirshahi", "Seyed Ali", "" ], [ "Hayn-Leichsenring", "Gregor Uwe", "" ], [ "Denzler", "Joachim", "" ], [ "Redies", "Christoph", "" ] ]
TITLE: Color: A Crucial Factor for Aesthetic Quality Assessment in a Subjective Dataset of Paintings ABSTRACT: Computational aesthetics is an emerging field of research which has attracted different research groups in the last few years. In this field, one of the main approaches to evaluate the aesthetic quality of paintings and photographs is a feature-based approach. Among the different features proposed to reach this goal, color plays an import role. In this paper, we introduce a novel dataset that consists of paintings of Western provenance from 36 well-known painters from the 15th to the 20th century. As a first step and to assess this dataset, using a classifier, we investigate the correlation between the subjective scores and two widely used features that are related to color perception and in different aesthetic quality assessment approaches. Results show a classification rate of up to 73% between the color features and the subjective scores.
new_dataset
0.9601
1609.05619
Hassan Alhajj Hassan ALHAJJ
Hassan Al Hajj, Gwenol\'e Quellec, Mathieu Lamard, Guy Cazuguel, B\'eatrice Cochener
Coarse-to-fine Surgical Instrument Detection for Cataract Surgery Monitoring
null
null
null
null
cs.CV
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The amount of surgical data, recorded during video-monitored surgeries, has extremely increased. This paper aims at improving existing solutions for the automated analysis of cataract surgeries in real time. Through the analysis of a video recording the operating table, it is possible to know which instruments exit or enter the operating table, and therefore which ones are likely being used by the surgeon. Combining these observations with observations from the microscope video should enhance the overall performance of the systems. To this end, the proposed solution is divided into two main parts: one to detect the instruments at the beginning of the surgery and one to update the list of instruments every time a change is detected in the scene. In the first part, the goal is to separate the instruments from the background and from irrelevant objects. For the second, we are interested in detecting the instruments that appear and disappear whenever the surgeon interacts with the table. Experiments on a dataset of 36 cataract surgeries validate the good performance of the proposed solution.
[ { "version": "v1", "created": "Mon, 19 Sep 2016 07:40:41 GMT" } ]
2016-09-20T00:00:00
[ [ "Hajj", "Hassan Al", "" ], [ "Quellec", "Gwenolé", "" ], [ "Lamard", "Mathieu", "" ], [ "Cazuguel", "Guy", "" ], [ "Cochener", "Béatrice", "" ] ]
TITLE: Coarse-to-fine Surgical Instrument Detection for Cataract Surgery Monitoring ABSTRACT: The amount of surgical data, recorded during video-monitored surgeries, has extremely increased. This paper aims at improving existing solutions for the automated analysis of cataract surgeries in real time. Through the analysis of a video recording the operating table, it is possible to know which instruments exit or enter the operating table, and therefore which ones are likely being used by the surgeon. Combining these observations with observations from the microscope video should enhance the overall performance of the systems. To this end, the proposed solution is divided into two main parts: one to detect the instruments at the beginning of the surgery and one to update the list of instruments every time a change is detected in the scene. In the first part, the goal is to separate the instruments from the background and from irrelevant objects. For the second, we are interested in detecting the instruments that appear and disappear whenever the surgeon interacts with the table. Experiments on a dataset of 36 cataract surgeries validate the good performance of the proposed solution.
new_dataset
0.502594
1609.05787
Qiang Liu
Qiang Liu, Shu Wu, Diyi Wang, Zhaokang Li, Liang Wang
Context-aware Sequential Recommendation
IEEE International Conference on Data Mining (ICDM) 2016, to apear
null
null
null
cs.IR cs.AI
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Since sequential information plays an important role in modeling user behaviors, various sequential recommendation methods have been proposed. Methods based on Markov assumption are widely-used, but independently combine several most recent components. Recently, Recurrent Neural Networks (RNN) based methods have been successfully applied in several sequential modeling tasks. However, for real-world applications, these methods have difficulty in modeling the contextual information, which has been proved to be very important for behavior modeling. In this paper, we propose a novel model, named Context-Aware Recurrent Neural Networks (CA-RNN). Instead of using the constant input matrix and transition matrix in conventional RNN models, CA-RNN employs adaptive context-specific input matrices and adaptive context-specific transition matrices. The adaptive context-specific input matrices capture external situations where user behaviors happen, such as time, location, weather and so on. And the adaptive context-specific transition matrices capture how lengths of time intervals between adjacent behaviors in historical sequences affect the transition of global sequential features. Experimental results show that the proposed CA-RNN model yields significant improvements over state-of-the-art sequential recommendation methods and context-aware recommendation methods on two public datasets, i.e., the Taobao dataset and the Movielens-1M dataset.
[ { "version": "v1", "created": "Mon, 19 Sep 2016 15:33:46 GMT" } ]
2016-09-20T00:00:00
[ [ "Liu", "Qiang", "" ], [ "Wu", "Shu", "" ], [ "Wang", "Diyi", "" ], [ "Li", "Zhaokang", "" ], [ "Wang", "Liang", "" ] ]
TITLE: Context-aware Sequential Recommendation ABSTRACT: Since sequential information plays an important role in modeling user behaviors, various sequential recommendation methods have been proposed. Methods based on Markov assumption are widely-used, but independently combine several most recent components. Recently, Recurrent Neural Networks (RNN) based methods have been successfully applied in several sequential modeling tasks. However, for real-world applications, these methods have difficulty in modeling the contextual information, which has been proved to be very important for behavior modeling. In this paper, we propose a novel model, named Context-Aware Recurrent Neural Networks (CA-RNN). Instead of using the constant input matrix and transition matrix in conventional RNN models, CA-RNN employs adaptive context-specific input matrices and adaptive context-specific transition matrices. The adaptive context-specific input matrices capture external situations where user behaviors happen, such as time, location, weather and so on. And the adaptive context-specific transition matrices capture how lengths of time intervals between adjacent behaviors in historical sequences affect the transition of global sequential features. Experimental results show that the proposed CA-RNN model yields significant improvements over state-of-the-art sequential recommendation methods and context-aware recommendation methods on two public datasets, i.e., the Taobao dataset and the Movielens-1M dataset.
no_new_dataset
0.949248
1606.08117
Xinxing Xu
Yong Kiam Tan, Xinxing Xu and Yong Liu
Improved Recurrent Neural Networks for Session-based Recommendations
null
null
null
null
cs.LG
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Recurrent neural networks (RNNs) were recently proposed for the session-based recommendation task. The models showed promising improvements over traditional recommendation approaches. In this work, we further study RNN-based models for session-based recommendations. We propose the application of two techniques to improve model performance, namely, data augmentation, and a method to account for shifts in the input data distribution. We also empirically study the use of generalised distillation, and a novel alternative model that directly predicts item embeddings. Experiments on the RecSys Challenge 2015 dataset demonstrate relative improvements of 12.8% and 14.8% over previously reported results on the Recall@20 and Mean Reciprocal Rank@20 metrics respectively.
[ { "version": "v1", "created": "Mon, 27 Jun 2016 03:06:44 GMT" }, { "version": "v2", "created": "Fri, 16 Sep 2016 09:41:10 GMT" } ]
2016-09-19T00:00:00
[ [ "Tan", "Yong Kiam", "" ], [ "Xu", "Xinxing", "" ], [ "Liu", "Yong", "" ] ]
TITLE: Improved Recurrent Neural Networks for Session-based Recommendations ABSTRACT: Recurrent neural networks (RNNs) were recently proposed for the session-based recommendation task. The models showed promising improvements over traditional recommendation approaches. In this work, we further study RNN-based models for session-based recommendations. We propose the application of two techniques to improve model performance, namely, data augmentation, and a method to account for shifts in the input data distribution. We also empirically study the use of generalised distillation, and a novel alternative model that directly predicts item embeddings. Experiments on the RecSys Challenge 2015 dataset demonstrate relative improvements of 12.8% and 14.8% over previously reported results on the Recall@20 and Mean Reciprocal Rank@20 metrics respectively.
no_new_dataset
0.953101
1608.05180
Wenzheng Chen
Huayong Xu, Yangyan Li, Wenzheng Chen, Dani Lischinski, Daniel Cohen-Or, Baoquan Chen
A Holistic Approach for Data-Driven Object Cutout
null
null
null
null
cs.CV
http://creativecommons.org/licenses/by-nc-sa/4.0/
Object cutout is a fundamental operation for image editing and manipulation, yet it is extremely challenging to automate it in real-world images, which typically contain considerable background clutter. In contrast to existing cutout methods, which are based mainly on low-level image analysis, we propose a more holistic approach, which considers the entire shape of the object of interest by leveraging higher-level image analysis and learnt global shape priors. Specifically, we leverage a deep neural network (DNN) trained for objects of a particular class (chairs) for realizing this mechanism. Given a rectangular image region, the DNN outputs a probability map (P-map) that indicates for each pixel inside the rectangle how likely it is to be contained inside an object from the class of interest. We show that the resulting P-maps may be used to evaluate how likely a rectangle proposal is to contain an instance of the class, and further process good proposals to produce an accurate object cutout mask. This amounts to an automatic end-to-end pipeline for catergory-specific object cutout. We evaluate our approach on segmentation benchmark datasets, and show that it significantly outperforms the state-of-the-art on them.
[ { "version": "v1", "created": "Thu, 18 Aug 2016 05:19:26 GMT" }, { "version": "v2", "created": "Fri, 16 Sep 2016 13:00:21 GMT" } ]
2016-09-19T00:00:00
[ [ "Xu", "Huayong", "" ], [ "Li", "Yangyan", "" ], [ "Chen", "Wenzheng", "" ], [ "Lischinski", "Dani", "" ], [ "Cohen-Or", "Daniel", "" ], [ "Chen", "Baoquan", "" ] ]
TITLE: A Holistic Approach for Data-Driven Object Cutout ABSTRACT: Object cutout is a fundamental operation for image editing and manipulation, yet it is extremely challenging to automate it in real-world images, which typically contain considerable background clutter. In contrast to existing cutout methods, which are based mainly on low-level image analysis, we propose a more holistic approach, which considers the entire shape of the object of interest by leveraging higher-level image analysis and learnt global shape priors. Specifically, we leverage a deep neural network (DNN) trained for objects of a particular class (chairs) for realizing this mechanism. Given a rectangular image region, the DNN outputs a probability map (P-map) that indicates for each pixel inside the rectangle how likely it is to be contained inside an object from the class of interest. We show that the resulting P-maps may be used to evaluate how likely a rectangle proposal is to contain an instance of the class, and further process good proposals to produce an accurate object cutout mask. This amounts to an automatic end-to-end pipeline for catergory-specific object cutout. We evaluate our approach on segmentation benchmark datasets, and show that it significantly outperforms the state-of-the-art on them.
no_new_dataset
0.949669
1609.00626
Shinichi Nakajima
Shinichi Nakajima, Sebastian Krause, Dirk Weissenborn, Sven Schmeier, Nico Goernitz, Feiyu Xu
SynsetRank: Degree-adjusted Random Walk for Relation Identification
null
null
null
null
cs.CL stat.AP
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
In relation extraction, a key process is to obtain good detectors that find relevant sentences describing the target relation. To minimize the necessity of labeled data for refining detectors, previous work successfully made use of BabelNet, a semantic graph structure expressing relationships between synsets, as side information or prior knowledge. The goal of this paper is to enhance the use of graph structure in the framework of random walk with a few adjustable parameters. Actually, a straightforward application of random walk degrades the performance even after parameter optimization. With the insight from this unsuccessful trial, we propose SynsetRank, which adjusts the initial probability so that high degree nodes influence the neighbors as strong as low degree nodes. In our experiment on 13 relations in the FB15K-237 dataset, SynsetRank significantly outperforms baselines and the plain random walk approach.
[ { "version": "v1", "created": "Fri, 2 Sep 2016 14:42:18 GMT" }, { "version": "v2", "created": "Thu, 15 Sep 2016 22:46:29 GMT" } ]
2016-09-19T00:00:00
[ [ "Nakajima", "Shinichi", "" ], [ "Krause", "Sebastian", "" ], [ "Weissenborn", "Dirk", "" ], [ "Schmeier", "Sven", "" ], [ "Goernitz", "Nico", "" ], [ "Xu", "Feiyu", "" ] ]
TITLE: SynsetRank: Degree-adjusted Random Walk for Relation Identification ABSTRACT: In relation extraction, a key process is to obtain good detectors that find relevant sentences describing the target relation. To minimize the necessity of labeled data for refining detectors, previous work successfully made use of BabelNet, a semantic graph structure expressing relationships between synsets, as side information or prior knowledge. The goal of this paper is to enhance the use of graph structure in the framework of random walk with a few adjustable parameters. Actually, a straightforward application of random walk degrades the performance even after parameter optimization. With the insight from this unsuccessful trial, we propose SynsetRank, which adjusts the initial probability so that high degree nodes influence the neighbors as strong as low degree nodes. In our experiment on 13 relations in the FB15K-237 dataset, SynsetRank significantly outperforms baselines and the plain random walk approach.
no_new_dataset
0.947137
1609.04859
Rajmonda Caceres S
Rajmonda S. Caceres, Leah Weiner, Matthew C. Schmidt, Benjamin A. Miller, William M. Campbell
Model Selection Framework for Graph-based data
7 pages
null
null
null
cs.SI physics.soc-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Graphs are powerful abstractions for capturing complex relationships in diverse application settings. An active area of research focuses on theoretical models that define the generative mechanism of a graph. Yet given the complexity and inherent noise in real datasets, it is still very challenging to identify the best model for a given observed graph. We discuss a framework for graph model selection that leverages a long list of graph topological properties and a random forest classifier to learn and classify different graph instances. We fully characterize the discriminative power of our approach as we sweep through the parameter space of two generative models, the Erdos-Renyi and the stochastic block model. We show that our approach gets very close to known theoretical bounds and we provide insight on which topological features play a critical discriminating role.
[ { "version": "v1", "created": "Thu, 15 Sep 2016 21:00:56 GMT" } ]
2016-09-19T00:00:00
[ [ "Caceres", "Rajmonda S.", "" ], [ "Weiner", "Leah", "" ], [ "Schmidt", "Matthew C.", "" ], [ "Miller", "Benjamin A.", "" ], [ "Campbell", "William M.", "" ] ]
TITLE: Model Selection Framework for Graph-based data ABSTRACT: Graphs are powerful abstractions for capturing complex relationships in diverse application settings. An active area of research focuses on theoretical models that define the generative mechanism of a graph. Yet given the complexity and inherent noise in real datasets, it is still very challenging to identify the best model for a given observed graph. We discuss a framework for graph model selection that leverages a long list of graph topological properties and a random forest classifier to learn and classify different graph instances. We fully characterize the discriminative power of our approach as we sweep through the parameter space of two generative models, the Erdos-Renyi and the stochastic block model. We show that our approach gets very close to known theoretical bounds and we provide insight on which topological features play a critical discriminating role.
no_new_dataset
0.947284
1609.05096
Yongchao Tian
Yongchao Tian, Ioannis Alagiannis, Erietta Liarou, Anastasia Ailamaki, Pietro Michiardi, Marko Vukolic
DiNoDB: an Interactive-speed Query Engine for Ad-hoc Queries on Temporary Data
null
null
null
null
cs.DB cs.DC
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
As data sets grow in size, analytics applications struggle to get instant insight into large datasets. Modern applications involve heavy batch processing jobs over large volumes of data and at the same time require efficient ad-hoc interactive analytics on temporary data. Existing solutions, however, typically focus on one of these two aspects, largely ignoring the need for synergy between the two. Consequently, interactive queries need to re-iterate costly passes through the entire dataset (e.g., data loading) that may provide meaningful return on investment only when data is queried over a long period of time. In this paper, we propose DiNoDB, an interactive-speed query engine for ad-hoc queries on temporary data. DiNoDB avoids the expensive loading and transformation phase that characterizes both traditional RDBMSs and current interactive analytics solutions. It is tailored to modern workflows found in machine learning and data exploration use cases, which often involve iterations of cycles of batch and interactive analytics on data that is typically useful for a narrow processing window. The key innovation of DiNoDB is to piggyback on the batch processing phase the creation of metadata that DiNoDB exploits to expedite the interactive queries. Our experimental analysis demonstrates that DiNoDB achieves very good performance for a wide range of ad-hoc queries compared to alternatives %such as Hive, Stado, SparkSQL and Impala.
[ { "version": "v1", "created": "Fri, 16 Sep 2016 14:56:31 GMT" } ]
2016-09-19T00:00:00
[ [ "Tian", "Yongchao", "" ], [ "Alagiannis", "Ioannis", "" ], [ "Liarou", "Erietta", "" ], [ "Ailamaki", "Anastasia", "" ], [ "Michiardi", "Pietro", "" ], [ "Vukolic", "Marko", "" ] ]
TITLE: DiNoDB: an Interactive-speed Query Engine for Ad-hoc Queries on Temporary Data ABSTRACT: As data sets grow in size, analytics applications struggle to get instant insight into large datasets. Modern applications involve heavy batch processing jobs over large volumes of data and at the same time require efficient ad-hoc interactive analytics on temporary data. Existing solutions, however, typically focus on one of these two aspects, largely ignoring the need for synergy between the two. Consequently, interactive queries need to re-iterate costly passes through the entire dataset (e.g., data loading) that may provide meaningful return on investment only when data is queried over a long period of time. In this paper, we propose DiNoDB, an interactive-speed query engine for ad-hoc queries on temporary data. DiNoDB avoids the expensive loading and transformation phase that characterizes both traditional RDBMSs and current interactive analytics solutions. It is tailored to modern workflows found in machine learning and data exploration use cases, which often involve iterations of cycles of batch and interactive analytics on data that is typically useful for a narrow processing window. The key innovation of DiNoDB is to piggyback on the batch processing phase the creation of metadata that DiNoDB exploits to expedite the interactive queries. Our experimental analysis demonstrates that DiNoDB achieves very good performance for a wide range of ad-hoc queries compared to alternatives %such as Hive, Stado, SparkSQL and Impala.
no_new_dataset
0.944022
1609.05112
Hamid Tizhoosh
Hamid R. Tizhoosh, Christopher Mitcheltree, Shujin Zhu, Shamak Dutta
Barcodes for Medical Image Retrieval Using Autoencoded Radon Transform
o appear in proceedings of the 23rd International Conference on Pattern Recognition (ICPR 2016), Cancun, Mexico, December 2016
null
null
null
cs.CV
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Using content-based binary codes to tag digital images has emerged as a promising retrieval technology. Recently, Radon barcodes (RBCs) have been introduced as a new binary descriptor for image search. RBCs are generated by binarization of Radon projections and by assembling them into a vector, namely the barcode. A simple local thresholding has been suggested for binarization. In this paper, we put forward the idea of "autoencoded Radon barcodes". Using images in a training dataset, we autoencode Radon projections to perform binarization on outputs of hidden layers. We employed the mini-batch stochastic gradient descent approach for the training. Each hidden layer of the autoencoder can produce a barcode using a threshold determined based on the range of the logistic function used. The compressing capability of autoencoders apparently reduces the redundancies inherent in Radon projections leading to more accurate retrieval results. The IRMA dataset with 14,410 x-ray images is used to validate the performance of the proposed method. The experimental results, containing comparison with RBCs, SURF and BRISK, show that autoencoded Radon barcode (ARBC) has the capacity to capture important information and to learn richer representations resulting in lower retrieval errors for image retrieval measured with the accuracy of the first hit only.
[ { "version": "v1", "created": "Fri, 16 Sep 2016 15:51:24 GMT" } ]
2016-09-19T00:00:00
[ [ "Tizhoosh", "Hamid R.", "" ], [ "Mitcheltree", "Christopher", "" ], [ "Zhu", "Shujin", "" ], [ "Dutta", "Shamak", "" ] ]
TITLE: Barcodes for Medical Image Retrieval Using Autoencoded Radon Transform ABSTRACT: Using content-based binary codes to tag digital images has emerged as a promising retrieval technology. Recently, Radon barcodes (RBCs) have been introduced as a new binary descriptor for image search. RBCs are generated by binarization of Radon projections and by assembling them into a vector, namely the barcode. A simple local thresholding has been suggested for binarization. In this paper, we put forward the idea of "autoencoded Radon barcodes". Using images in a training dataset, we autoencode Radon projections to perform binarization on outputs of hidden layers. We employed the mini-batch stochastic gradient descent approach for the training. Each hidden layer of the autoencoder can produce a barcode using a threshold determined based on the range of the logistic function used. The compressing capability of autoencoders apparently reduces the redundancies inherent in Radon projections leading to more accurate retrieval results. The IRMA dataset with 14,410 x-ray images is used to validate the performance of the proposed method. The experimental results, containing comparison with RBCs, SURF and BRISK, show that autoencoded Radon barcode (ARBC) has the capacity to capture important information and to learn richer representations resulting in lower retrieval errors for image retrieval measured with the accuracy of the first hit only.
no_new_dataset
0.881513
1609.05115
Christian Richardt
Christian Richardt, Hyeongwoo Kim, Levi Valgaerts, Christian Theobalt
Dense Wide-Baseline Scene Flow From Two Handheld Video Cameras
11 pages, supplemental document included as appendix, 3DV 2016
null
null
null
cs.CV
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We propose a new technique for computing dense scene flow from two handheld videos with wide camera baselines and different photometric properties due to different sensors or camera settings like exposure and white balance. Our technique innovates in two ways over existing methods: (1) it supports independently moving cameras, and (2) it computes dense scene flow for wide-baseline scenarios.We achieve this by combining state-of-the-art wide-baseline correspondence finding with a variational scene flow formulation. First, we compute dense, wide-baseline correspondences using DAISY descriptors for matching between cameras and over time. We then detect and replace occluded pixels in the correspondence fields using a novel edge-preserving Laplacian correspondence completion technique. We finally refine the computed correspondence fields in a variational scene flow formulation. We show dense scene flow results computed from challenging datasets with independently moving, handheld cameras of varying camera settings.
[ { "version": "v1", "created": "Fri, 16 Sep 2016 15:54:46 GMT" } ]
2016-09-19T00:00:00
[ [ "Richardt", "Christian", "" ], [ "Kim", "Hyeongwoo", "" ], [ "Valgaerts", "Levi", "" ], [ "Theobalt", "Christian", "" ] ]
TITLE: Dense Wide-Baseline Scene Flow From Two Handheld Video Cameras ABSTRACT: We propose a new technique for computing dense scene flow from two handheld videos with wide camera baselines and different photometric properties due to different sensors or camera settings like exposure and white balance. Our technique innovates in two ways over existing methods: (1) it supports independently moving cameras, and (2) it computes dense scene flow for wide-baseline scenarios.We achieve this by combining state-of-the-art wide-baseline correspondence finding with a variational scene flow formulation. First, we compute dense, wide-baseline correspondences using DAISY descriptors for matching between cameras and over time. We then detect and replace occluded pixels in the correspondence fields using a novel edge-preserving Laplacian correspondence completion technique. We finally refine the computed correspondence fields in a variational scene flow formulation. We show dense scene flow results computed from challenging datasets with independently moving, handheld cameras of varying camera settings.
no_new_dataset
0.954942
1609.05118
Hamid Tizhoosh
Mina Nouredanesh, H.R. Tizhoosh, Ershad Banijamali, James Tung
Radon-Gabor Barcodes for Medical Image Retrieval
To appear in proceedings of the 23rd International Conference on Pattern Recognition (ICPR 2016), Cancun, Mexico, December 2016
null
null
null
cs.CV
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
In recent years, with the explosion of digital images on the Web, content-based retrieval has emerged as a significant research area. Shapes, textures, edges and segments may play a key role in describing the content of an image. Radon and Gabor transforms are both powerful techniques that have been widely studied to extract shape-texture-based information. The combined Radon-Gabor features may be more robust against scale/rotation variations, presence of noise, and illumination changes. The objective of this paper is to harness the potentials of both Gabor and Radon transforms in order to introduce expressive binary features, called barcodes, for image annotation/tagging tasks. We propose two different techniques: Gabor-of-Radon-Image Barcodes (GRIBCs), and Guided-Radon-of-Gabor Barcodes (GRGBCs). For validation, we employ the IRMA x-ray dataset with 193 classes, containing 12,677 training images and 1,733 test images. A total error score as low as 322 and 330 were achieved for GRGBCs and GRIBCs, respectively. This corresponds to $\approx 81\%$ retrieval accuracy for the first hit.
[ { "version": "v1", "created": "Fri, 16 Sep 2016 16:01:43 GMT" } ]
2016-09-19T00:00:00
[ [ "Nouredanesh", "Mina", "" ], [ "Tizhoosh", "H. R.", "" ], [ "Banijamali", "Ershad", "" ], [ "Tung", "James", "" ] ]
TITLE: Radon-Gabor Barcodes for Medical Image Retrieval ABSTRACT: In recent years, with the explosion of digital images on the Web, content-based retrieval has emerged as a significant research area. Shapes, textures, edges and segments may play a key role in describing the content of an image. Radon and Gabor transforms are both powerful techniques that have been widely studied to extract shape-texture-based information. The combined Radon-Gabor features may be more robust against scale/rotation variations, presence of noise, and illumination changes. The objective of this paper is to harness the potentials of both Gabor and Radon transforms in order to introduce expressive binary features, called barcodes, for image annotation/tagging tasks. We propose two different techniques: Gabor-of-Radon-Image Barcodes (GRIBCs), and Guided-Radon-of-Gabor Barcodes (GRGBCs). For validation, we employ the IRMA x-ray dataset with 193 classes, containing 12,677 training images and 1,733 test images. A total error score as low as 322 and 330 were achieved for GRGBCs and GRIBCs, respectively. This corresponds to $\approx 81\%$ retrieval accuracy for the first hit.
no_new_dataset
0.949482
1408.1292
Ilja Kuzborskij
Ilja Kuzborskij, Francesco Orabona, Barbara Caputo
Scalable Greedy Algorithms for Transfer Learning
null
null
10.1016/j.cviu.2016.09.003
null
cs.CV cs.LG
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
In this paper we consider the binary transfer learning problem, focusing on how to select and combine sources from a large pool to yield a good performance on a target task. Constraining our scenario to real world, we do not assume the direct access to the source data, but rather we employ the source hypotheses trained from them. We propose an efficient algorithm that selects relevant source hypotheses and feature dimensions simultaneously, building on the literature on the best subset selection problem. Our algorithm achieves state-of-the-art results on three computer vision datasets, substantially outperforming both transfer learning and popular feature selection baselines in a small-sample setting. We also present a randomized variant that achieves the same results with the computational cost independent from the number of source hypotheses and feature dimensions. Also, we theoretically prove that, under reasonable assumptions on the source hypotheses, our algorithm can learn effectively from few examples.
[ { "version": "v1", "created": "Wed, 6 Aug 2014 14:27:57 GMT" }, { "version": "v2", "created": "Thu, 4 Dec 2014 15:56:53 GMT" }, { "version": "v3", "created": "Thu, 8 Oct 2015 10:27:39 GMT" }, { "version": "v4", "created": "Sat, 18 Jun 2016 00:17:50 GMT" } ]
2016-09-16T00:00:00
[ [ "Kuzborskij", "Ilja", "" ], [ "Orabona", "Francesco", "" ], [ "Caputo", "Barbara", "" ] ]
TITLE: Scalable Greedy Algorithms for Transfer Learning ABSTRACT: In this paper we consider the binary transfer learning problem, focusing on how to select and combine sources from a large pool to yield a good performance on a target task. Constraining our scenario to real world, we do not assume the direct access to the source data, but rather we employ the source hypotheses trained from them. We propose an efficient algorithm that selects relevant source hypotheses and feature dimensions simultaneously, building on the literature on the best subset selection problem. Our algorithm achieves state-of-the-art results on three computer vision datasets, substantially outperforming both transfer learning and popular feature selection baselines in a small-sample setting. We also present a randomized variant that achieves the same results with the computational cost independent from the number of source hypotheses and feature dimensions. Also, we theoretically prove that, under reasonable assumptions on the source hypotheses, our algorithm can learn effectively from few examples.
no_new_dataset
0.950686
1608.08905
Rajasekar Venkatesan
Rajasekar Venkatesan, Meng Joo Er, Shiqian Wu, Mahardhika Pratama
A Novel Online Real-time Classifier for Multi-label Data Streams
8 pages, 7 tables, 3 figures. arXiv admin note: text overlap with arXiv:1609.00086
null
null
null
cs.LG cs.AI cs.NE
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
In this paper, a novel extreme learning machine based online multi-label classifier for real-time data streams is proposed. Multi-label classification is one of the actively researched machine learning paradigm that has gained much attention in the recent years due to its rapidly increasing real world applications. In contrast to traditional binary and multi-class classification, multi-label classification involves association of each of the input samples with a set of target labels simultaneously. There are no real-time online neural network based multi-label classifier available in the literature. In this paper, we exploit the inherent nature of high speed exhibited by the extreme learning machines to develop a novel online real-time classifier for multi-label data streams. The developed classifier is experimented with datasets from different application domains for consistency, performance and speed. The experimental studies show that the proposed method outperforms the existing state-of-the-art techniques in terms of speed and accuracy and can classify multi-label data streams in real-time.
[ { "version": "v1", "created": "Wed, 31 Aug 2016 15:14:06 GMT" } ]
2016-09-16T00:00:00
[ [ "Venkatesan", "Rajasekar", "" ], [ "Er", "Meng Joo", "" ], [ "Wu", "Shiqian", "" ], [ "Pratama", "Mahardhika", "" ] ]
TITLE: A Novel Online Real-time Classifier for Multi-label Data Streams ABSTRACT: In this paper, a novel extreme learning machine based online multi-label classifier for real-time data streams is proposed. Multi-label classification is one of the actively researched machine learning paradigm that has gained much attention in the recent years due to its rapidly increasing real world applications. In contrast to traditional binary and multi-class classification, multi-label classification involves association of each of the input samples with a set of target labels simultaneously. There are no real-time online neural network based multi-label classifier available in the literature. In this paper, we exploit the inherent nature of high speed exhibited by the extreme learning machines to develop a novel online real-time classifier for multi-label data streams. The developed classifier is experimented with datasets from different application domains for consistency, performance and speed. The experimental studies show that the proposed method outperforms the existing state-of-the-art techniques in terms of speed and accuracy and can classify multi-label data streams in real-time.
no_new_dataset
0.952086
1609.04453
Terrell Mundhenk
T. Nathan Mundhenk, Goran Konjevod, Wesam A. Sakla, Kofi Boakye
A Large Contextual Dataset for Classification, Detection and Counting of Cars with Deep Learning
ECCV 2016 Pre-press revision
null
null
null
cs.CV cs.DC cs.NE
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We have created a large diverse set of cars from overhead images, which are useful for training a deep learner to binary classify, detect and count them. The dataset and all related material will be made publically available. The set contains contextual matter to aid in identification of difficult targets. We demonstrate classification and detection on this dataset using a neural network we call ResCeption. This network combines residual learning with Inception-style layers and is used to count cars in one look. This is a new way to count objects rather than by localization or density estimation. It is fairly accurate, fast and easy to implement. Additionally, the counting method is not car or scene specific. It would be easy to train this method to count other kinds of objects and counting over new scenes requires no extra set up or assumptions about object locations.
[ { "version": "v1", "created": "Wed, 14 Sep 2016 21:44:58 GMT" } ]
2016-09-16T00:00:00
[ [ "Mundhenk", "T. Nathan", "" ], [ "Konjevod", "Goran", "" ], [ "Sakla", "Wesam A.", "" ], [ "Boakye", "Kofi", "" ] ]
TITLE: A Large Contextual Dataset for Classification, Detection and Counting of Cars with Deep Learning ABSTRACT: We have created a large diverse set of cars from overhead images, which are useful for training a deep learner to binary classify, detect and count them. The dataset and all related material will be made publically available. The set contains contextual matter to aid in identification of difficult targets. We demonstrate classification and detection on this dataset using a neural network we call ResCeption. This network combines residual learning with Inception-style layers and is used to count cars in one look. This is a new way to count objects rather than by localization or density estimation. It is fairly accurate, fast and easy to implement. Additionally, the counting method is not car or scene specific. It would be easy to train this method to count other kinds of objects and counting over new scenes requires no extra set up or assumptions about object locations.
new_dataset
0.962285
1609.04504
Brett Naul
Brett Naul, St\'efan van der Walt, Arien Crellin-Quick, Joshua S. Bloom, Fernando P\'erez
cesium: Open-Source Platform for Time-Series Inference
Proceedings of the 15th Python in Science Conference (SciPy 2016)
null
null
null
cs.MS
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Inference on time series data is a common requirement in many scientific disciplines and internet of things (IoT) applications, yet there are few resources available to domain scientists to easily, robustly, and repeatably build such complex inference workflows: traditional statistical models of time series are often too rigid to explain complex time domain behavior, while popular machine learning packages require already-featurized dataset inputs. Moreover, the software engineering tasks required to instantiate the computational platform are daunting. cesium is an end-to-end time series analysis framework, consisting of a Python library as well as a web front-end interface, that allows researchers to featurize raw data and apply modern machine learning techniques in a simple, reproducible, and extensible way. Users can apply out-of-the-box feature engineering workflows as well as save and replay their own analyses. Any steps taken in the front end can also be exported to a Jupyter notebook, so users can iterate between possible models within the front end and then fine-tune their analysis using the additional capabilities of the back-end library. The open-source packages make us of many use modern Python toolkits, including xarray, dask, Celery, Flask, and scikit-learn.
[ { "version": "v1", "created": "Thu, 15 Sep 2016 04:09:48 GMT" } ]
2016-09-16T00:00:00
[ [ "Naul", "Brett", "" ], [ "van der Walt", "Stéfan", "" ], [ "Crellin-Quick", "Arien", "" ], [ "Bloom", "Joshua S.", "" ], [ "Pérez", "Fernando", "" ] ]
TITLE: cesium: Open-Source Platform for Time-Series Inference ABSTRACT: Inference on time series data is a common requirement in many scientific disciplines and internet of things (IoT) applications, yet there are few resources available to domain scientists to easily, robustly, and repeatably build such complex inference workflows: traditional statistical models of time series are often too rigid to explain complex time domain behavior, while popular machine learning packages require already-featurized dataset inputs. Moreover, the software engineering tasks required to instantiate the computational platform are daunting. cesium is an end-to-end time series analysis framework, consisting of a Python library as well as a web front-end interface, that allows researchers to featurize raw data and apply modern machine learning techniques in a simple, reproducible, and extensible way. Users can apply out-of-the-box feature engineering workflows as well as save and replay their own analyses. Any steps taken in the front end can also be exported to a Jupyter notebook, so users can iterate between possible models within the front end and then fine-tune their analysis using the additional capabilities of the back-end library. The open-source packages make us of many use modern Python toolkits, including xarray, dask, Celery, Flask, and scikit-learn.
no_new_dataset
0.935582
1609.04556
Djoerd Hiemstra
Dong Nguyen, Thomas Demeester, Dolf Trieschnigg, Djoerd Hiemstra
Resource Selection for Federated Search on the Web
CTIT Technical Report, University of Twente
null
null
null
cs.IR
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
A publicly available dataset for federated search reflecting a real web environment has long been absent, making it difficult for researchers to test the validity of their federated search algorithms for the web setting. We present several experiments and analyses on resource selection on the web using a recently released test collection containing the results from more than a hundred real search engines, ranging from large general web search engines such as Google, Bing and Yahoo to small domain-specific engines. First, we experiment with estimating the size of uncooperative search engines on the web using query based sampling and propose a new method using the ClueWeb09 dataset. We find the size estimates to be highly effective in resource selection. Second, we show that an optimized federated search system based on smaller web search engines can be an alternative to a system using large web search engines. Third, we provide an empirical comparison of several popular resource selection methods and find that these methods are not readily suitable for resource selection on the web. Challenges include the sparse resource descriptions and extremely skewed sizes of collections.
[ { "version": "v1", "created": "Thu, 15 Sep 2016 09:49:27 GMT" } ]
2016-09-16T00:00:00
[ [ "Nguyen", "Dong", "" ], [ "Demeester", "Thomas", "" ], [ "Trieschnigg", "Dolf", "" ], [ "Hiemstra", "Djoerd", "" ] ]
TITLE: Resource Selection for Federated Search on the Web ABSTRACT: A publicly available dataset for federated search reflecting a real web environment has long been absent, making it difficult for researchers to test the validity of their federated search algorithms for the web setting. We present several experiments and analyses on resource selection on the web using a recently released test collection containing the results from more than a hundred real search engines, ranging from large general web search engines such as Google, Bing and Yahoo to small domain-specific engines. First, we experiment with estimating the size of uncooperative search engines on the web using query based sampling and propose a new method using the ClueWeb09 dataset. We find the size estimates to be highly effective in resource selection. Second, we show that an optimized federated search system based on smaller web search engines can be an alternative to a system using large web search engines. Third, we provide an empirical comparison of several popular resource selection methods and find that these methods are not readily suitable for resource selection on the web. Challenges include the sparse resource descriptions and extremely skewed sizes of collections.
new_dataset
0.926037
1609.04653
Peter Pinggera
Peter Pinggera, Sebastian Ramos, Stefan Gehrig, Uwe Franke, Carsten Rother, Rudolf Mester
Lost and Found: Detecting Small Road Hazards for Self-Driving Vehicles
To be presented at IEEE/RSJ International Conference on Intelligent Robots and Systems (IROS) 2016
null
null
null
cs.CV cs.RO
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Detecting small obstacles on the road ahead is a critical part of the driving task which has to be mastered by fully autonomous cars. In this paper, we present a method based on stereo vision to reliably detect such obstacles from a moving vehicle. The proposed algorithm performs statistical hypothesis tests in disparity space directly on stereo image data, assessing freespace and obstacle hypotheses on independent local patches. This detection approach does not depend on a global road model and handles both static and moving obstacles. For evaluation, we employ a novel lost-cargo image sequence dataset comprising more than two thousand frames with pixelwise annotations of obstacle and free-space and provide a thorough comparison to several stereo-based baseline methods. The dataset will be made available to the community to foster further research on this important topic. The proposed approach outperforms all considered baselines in our evaluations on both pixel and object level and runs at frame rates of up to 20 Hz on 2 mega-pixel stereo imagery. Small obstacles down to the height of 5 cm can successfully be detected at 20 m distance at low false positive rates.
[ { "version": "v1", "created": "Thu, 15 Sep 2016 14:01:03 GMT" } ]
2016-09-16T00:00:00
[ [ "Pinggera", "Peter", "" ], [ "Ramos", "Sebastian", "" ], [ "Gehrig", "Stefan", "" ], [ "Franke", "Uwe", "" ], [ "Rother", "Carsten", "" ], [ "Mester", "Rudolf", "" ] ]
TITLE: Lost and Found: Detecting Small Road Hazards for Self-Driving Vehicles ABSTRACT: Detecting small obstacles on the road ahead is a critical part of the driving task which has to be mastered by fully autonomous cars. In this paper, we present a method based on stereo vision to reliably detect such obstacles from a moving vehicle. The proposed algorithm performs statistical hypothesis tests in disparity space directly on stereo image data, assessing freespace and obstacle hypotheses on independent local patches. This detection approach does not depend on a global road model and handles both static and moving obstacles. For evaluation, we employ a novel lost-cargo image sequence dataset comprising more than two thousand frames with pixelwise annotations of obstacle and free-space and provide a thorough comparison to several stereo-based baseline methods. The dataset will be made available to the community to foster further research on this important topic. The proposed approach outperforms all considered baselines in our evaluations on both pixel and object level and runs at frame rates of up to 20 Hz on 2 mega-pixel stereo imagery. Small obstacles down to the height of 5 cm can successfully be detected at 20 m distance at low false positive rates.
new_dataset
0.9601
1609.04718
Paul Irolla
Paul Irolla and Eric Filiol
Glassbox: Dynamic Analysis Platform for Malware Android Applications on Real Devices
11 pages, 4 figures. This paper have been submitted to the ICISSP workshop FORmal methods for Security Engineering (ForSE 2017)
null
null
null
cs.CR
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Android is the most widely used smartphone OS with 82.8% market share in 2015. It is therefore the most widely targeted system by malware authors. Researchers rely on dynamic analysis to extract malware behaviors and often use emulators to do so. However, using emulators lead to new issues. Malware may detect emulation and as a result it does not execute the payload to prevent the analysis. Dealing with virtual device evasion is a never-ending war and comes with a non-negligible computation cost. To overcome this state of affairs, we propose a system that does not use virtual devices for analysing malware behavior. Glassbox is a functional prototype for the dynamic analysis of malware applications. It executes applications on real devices in a monitored and controlled environment. It is a fully automated system that installs, tests and extracts features from the application for further analysis. We present the architecture of the platform and we compare it with existing Android dynamic analysis platforms. Lastly, we evaluate the capacity of Glassbox to trigger application behaviors by measuring the average coverage of basic blocks on the AndroCoverage dataset. We show that it executes on average 13.52% more basic blocks than the Monkey program.
[ { "version": "v1", "created": "Thu, 15 Sep 2016 16:16:56 GMT" } ]
2016-09-16T00:00:00
[ [ "Irolla", "Paul", "" ], [ "Filiol", "Eric", "" ] ]
TITLE: Glassbox: Dynamic Analysis Platform for Malware Android Applications on Real Devices ABSTRACT: Android is the most widely used smartphone OS with 82.8% market share in 2015. It is therefore the most widely targeted system by malware authors. Researchers rely on dynamic analysis to extract malware behaviors and often use emulators to do so. However, using emulators lead to new issues. Malware may detect emulation and as a result it does not execute the payload to prevent the analysis. Dealing with virtual device evasion is a never-ending war and comes with a non-negligible computation cost. To overcome this state of affairs, we propose a system that does not use virtual devices for analysing malware behavior. Glassbox is a functional prototype for the dynamic analysis of malware applications. It executes applications on real devices in a monitored and controlled environment. It is a fully automated system that installs, tests and extracts features from the application for further analysis. We present the architecture of the platform and we compare it with existing Android dynamic analysis platforms. Lastly, we evaluate the capacity of Glassbox to trigger application behaviors by measuring the average coverage of basic blocks on the AndroCoverage dataset. We show that it executes on average 13.52% more basic blocks than the Monkey program.
no_new_dataset
0.934932
1511.04590
Li Yao
Li Yao, Nicolas Ballas, Kyunghyun Cho, John R. Smith, Yoshua Bengio
Oracle performance for visual captioning
BMVC2016 (Oral paper)
null
null
null
cs.CV cs.CL stat.ML
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The task of associating images and videos with a natural language description has attracted a great amount of attention recently. Rapid progress has been made in terms of both developing novel algorithms and releasing new datasets. Indeed, the state-of-the-art results on some of the standard datasets have been pushed into the regime where it has become more and more difficult to make significant improvements. Instead of proposing new models, this work investigates the possibility of empirically establishing performance upper bounds on various visual captioning datasets without extra data labelling effort or human evaluation. In particular, it is assumed that visual captioning is decomposed into two steps: from visual inputs to visual concepts, and from visual concepts to natural language descriptions. One would be able to obtain an upper bound when assuming the first step is perfect and only requiring training a conditional language model for the second step. We demonstrate the construction of such bounds on MS-COCO, YouTube2Text and LSMDC (a combination of M-VAD and MPII-MD). Surprisingly, despite of the imperfect process we used for visual concept extraction in the first step and the simplicity of the language model for the second step, we show that current state-of-the-art models fall short when being compared with the learned upper bounds. Furthermore, with such a bound, we quantify several important factors concerning image and video captioning: the number of visual concepts captured by different models, the trade-off between the amount of visual elements captured and their accuracy, and the intrinsic difficulty and blessing of different datasets.
[ { "version": "v1", "created": "Sat, 14 Nov 2015 18:02:39 GMT" }, { "version": "v2", "created": "Wed, 18 Nov 2015 04:20:08 GMT" }, { "version": "v3", "created": "Sun, 3 Jan 2016 04:55:57 GMT" }, { "version": "v4", "created": "Wed, 6 Jan 2016 23:38:25 GMT" }, { "version": "v5", "created": "Wed, 14 Sep 2016 16:55:29 GMT" } ]
2016-09-15T00:00:00
[ [ "Yao", "Li", "" ], [ "Ballas", "Nicolas", "" ], [ "Cho", "Kyunghyun", "" ], [ "Smith", "John R.", "" ], [ "Bengio", "Yoshua", "" ] ]
TITLE: Oracle performance for visual captioning ABSTRACT: The task of associating images and videos with a natural language description has attracted a great amount of attention recently. Rapid progress has been made in terms of both developing novel algorithms and releasing new datasets. Indeed, the state-of-the-art results on some of the standard datasets have been pushed into the regime where it has become more and more difficult to make significant improvements. Instead of proposing new models, this work investigates the possibility of empirically establishing performance upper bounds on various visual captioning datasets without extra data labelling effort or human evaluation. In particular, it is assumed that visual captioning is decomposed into two steps: from visual inputs to visual concepts, and from visual concepts to natural language descriptions. One would be able to obtain an upper bound when assuming the first step is perfect and only requiring training a conditional language model for the second step. We demonstrate the construction of such bounds on MS-COCO, YouTube2Text and LSMDC (a combination of M-VAD and MPII-MD). Surprisingly, despite of the imperfect process we used for visual concept extraction in the first step and the simplicity of the language model for the second step, we show that current state-of-the-art models fall short when being compared with the learned upper bounds. Furthermore, with such a bound, we quantify several important factors concerning image and video captioning: the number of visual concepts captured by different models, the trade-off between the amount of visual elements captured and their accuracy, and the intrinsic difficulty and blessing of different datasets.
no_new_dataset
0.9455
1608.07094
Mahamad Suhil
D S Guru, Mahamad Suhil
A Novel Term_Class Relevance Measure for Text Categorization
12 pages, 6 figures, 2 tables
Procedia Computer Science, vol.45, pp.13-22, 2015
10.1016/j.procs.2015.03.074
null
cs.IR cs.CL
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
In this paper, we introduce a new measure called Term_Class relevance to compute the relevancy of a term in classifying a document into a particular class. The proposed measure estimates the degree of relevance of a given term, in placing an unlabeled document to be a member of a known class, as a product of Class_Term weight and Class_Term density; where the Class_Term weight is the ratio of the number of documents of the class containing the term to the total number of documents containing the term and the Class_Term density is the relative density of occurrence of the term in the class to the total occurrence of the term in the entire population. Unlike the other existing term weighting schemes such as TF-IDF and its variants, the proposed relevance measure takes into account the degree of relative participation of the term across all documents of the class to the entire population. To demonstrate the significance of the proposed measure experimentation has been conducted on the 20 Newsgroups dataset. Further, the superiority of the novel measure is brought out through a comparative analysis.
[ { "version": "v1", "created": "Thu, 25 Aug 2016 11:46:06 GMT" }, { "version": "v2", "created": "Wed, 14 Sep 2016 12:51:50 GMT" } ]
2016-09-15T00:00:00
[ [ "Guru", "D S", "" ], [ "Suhil", "Mahamad", "" ] ]
TITLE: A Novel Term_Class Relevance Measure for Text Categorization ABSTRACT: In this paper, we introduce a new measure called Term_Class relevance to compute the relevancy of a term in classifying a document into a particular class. The proposed measure estimates the degree of relevance of a given term, in placing an unlabeled document to be a member of a known class, as a product of Class_Term weight and Class_Term density; where the Class_Term weight is the ratio of the number of documents of the class containing the term to the total number of documents containing the term and the Class_Term density is the relative density of occurrence of the term in the class to the total occurrence of the term in the entire population. Unlike the other existing term weighting schemes such as TF-IDF and its variants, the proposed relevance measure takes into account the degree of relative participation of the term across all documents of the class to the entire population. To demonstrate the significance of the proposed measure experimentation has been conducted on the 20 Newsgroups dataset. Further, the superiority of the novel measure is brought out through a comparative analysis.
no_new_dataset
0.950273
1609.04104
Morteza Mardani
Morteza Mardani, Georgios B. Giannakis, and Kamil Ugurbil
Tracking Tensor Subspaces with Informative Random Sampling for Real-Time MR Imaging
null
null
null
null
cs.LG cs.CV cs.IT math.IT stat.CO
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Magnetic resonance imaging (MRI) nowadays serves as an important modality for diagnostic and therapeutic guidance in clinics. However, the {\it slow acquisition} process, the dynamic deformation of organs, as well as the need for {\it real-time} reconstruction, pose major challenges toward obtaining artifact-free images. To cope with these challenges, the present paper advocates a novel subspace learning framework that permeates benefits from parallel factor (PARAFAC) decomposition of tensors (multiway data) to low-rank modeling of temporal sequence of images. Treating images as multiway data arrays, the novel method preserves spatial structures and unravels the latent correlations across various dimensions by means of the tensor subspace. Leveraging the spatio-temporal correlation of images, Tykhonov regularization is adopted as a rank surrogate for a least-squares optimization program. Alteranating majorization minimization is adopted to develop online algorithms that recursively procure the reconstruction upon arrival of a new undersampled $k$-space frame. The developed algorithms are {\it provably convergent} and highly {\it parallelizable} with lightweight FFT tasks per iteration. To further accelerate the acquisition process, randomized subsampling policies are devised that leverage intermediate estimates of the tensor subspace, offered by the online scheme, to {\it randomly} acquire {\it informative} $k$-space samples. In a nutshell, the novel approach enables tracking motion dynamics under low acquisition rates `on the fly.' GPU-based tests with real {\it in vivo} MRI datasets of cardiac cine images corroborate the merits of the novel approach relative to state-of-the-art alternatives.
[ { "version": "v1", "created": "Wed, 14 Sep 2016 01:23:05 GMT" } ]
2016-09-15T00:00:00
[ [ "Mardani", "Morteza", "" ], [ "Giannakis", "Georgios B.", "" ], [ "Ugurbil", "Kamil", "" ] ]
TITLE: Tracking Tensor Subspaces with Informative Random Sampling for Real-Time MR Imaging ABSTRACT: Magnetic resonance imaging (MRI) nowadays serves as an important modality for diagnostic and therapeutic guidance in clinics. However, the {\it slow acquisition} process, the dynamic deformation of organs, as well as the need for {\it real-time} reconstruction, pose major challenges toward obtaining artifact-free images. To cope with these challenges, the present paper advocates a novel subspace learning framework that permeates benefits from parallel factor (PARAFAC) decomposition of tensors (multiway data) to low-rank modeling of temporal sequence of images. Treating images as multiway data arrays, the novel method preserves spatial structures and unravels the latent correlations across various dimensions by means of the tensor subspace. Leveraging the spatio-temporal correlation of images, Tykhonov regularization is adopted as a rank surrogate for a least-squares optimization program. Alteranating majorization minimization is adopted to develop online algorithms that recursively procure the reconstruction upon arrival of a new undersampled $k$-space frame. The developed algorithms are {\it provably convergent} and highly {\it parallelizable} with lightweight FFT tasks per iteration. To further accelerate the acquisition process, randomized subsampling policies are devised that leverage intermediate estimates of the tensor subspace, offered by the online scheme, to {\it randomly} acquire {\it informative} $k$-space samples. In a nutshell, the novel approach enables tracking motion dynamics under low acquisition rates `on the fly.' GPU-based tests with real {\it in vivo} MRI datasets of cardiac cine images corroborate the merits of the novel approach relative to state-of-the-art alternatives.
no_new_dataset
0.948965
1609.04116
Songcan Chen
Qing Tian, Songcan Chen
Joint Gender Classification and Age Estimation by Nearly Orthogonalizing Their Semantic Spaces
null
null
null
null
cs.CV
http://creativecommons.org/licenses/by-nc-sa/4.0/
In human face-based biometrics, gender classification and age estimation are two typical learning tasks. Although a variety of approaches have been proposed to handle them, just a few of them are solved jointly, even so, these joint methods do not yet specifically concern the semantic difference between human gender and age, which is intuitively helpful for joint learning, consequently leaving us a room of further improving the performance. To this end, in this work we firstly propose a general learning framework for jointly estimating human gender and age by specially attempting to formulate such semantic relationships as a form of near-orthogonality regularization and then incorporate it into the objective of the joint learning framework. In order to evaluate the effectiveness of the proposed framework, we exemplify it by respectively taking the widely used binary-class SVM for gender classification, and two threshold-based ordinal regression methods (i.e., the discriminant learning for ordinal regression and support vector ordinal regression) for age estimation, and crucially coupling both through the proposed semantic formulation. Moreover, we develop its kernelized nonlinear counterpart by deriving a representer theorem for the joint learning strategy. Finally, through extensive experiments on three aging datasets FG-NET, Morph Album I and Morph Album II, we demonstrate the effectiveness and superiority of the proposed joint learning strategy.
[ { "version": "v1", "created": "Wed, 14 Sep 2016 02:45:37 GMT" } ]
2016-09-15T00:00:00
[ [ "Tian", "Qing", "" ], [ "Chen", "Songcan", "" ] ]
TITLE: Joint Gender Classification and Age Estimation by Nearly Orthogonalizing Their Semantic Spaces ABSTRACT: In human face-based biometrics, gender classification and age estimation are two typical learning tasks. Although a variety of approaches have been proposed to handle them, just a few of them are solved jointly, even so, these joint methods do not yet specifically concern the semantic difference between human gender and age, which is intuitively helpful for joint learning, consequently leaving us a room of further improving the performance. To this end, in this work we firstly propose a general learning framework for jointly estimating human gender and age by specially attempting to formulate such semantic relationships as a form of near-orthogonality regularization and then incorporate it into the objective of the joint learning framework. In order to evaluate the effectiveness of the proposed framework, we exemplify it by respectively taking the widely used binary-class SVM for gender classification, and two threshold-based ordinal regression methods (i.e., the discriminant learning for ordinal regression and support vector ordinal regression) for age estimation, and crucially coupling both through the proposed semantic formulation. Moreover, we develop its kernelized nonlinear counterpart by deriving a representer theorem for the joint learning strategy. Finally, through extensive experiments on three aging datasets FG-NET, Morph Album I and Morph Album II, we demonstrate the effectiveness and superiority of the proposed joint learning strategy.
no_new_dataset
0.946151
1609.04253
Amir H. Jadidinejad
Amir H. Jadidinejad
Neural Machine Transliteration: Preliminary Results
null
null
null
null
cs.CL
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Machine transliteration is the process of automatically transforming the script of a word from a source language to a target language, while preserving pronunciation. Sequence to sequence learning has recently emerged as a new paradigm in supervised learning. In this paper a character-based encoder-decoder model has been proposed that consists of two Recurrent Neural Networks. The encoder is a Bidirectional recurrent neural network that encodes a sequence of symbols into a fixed-length vector representation, and the decoder generates the target sequence using an attention-based recurrent neural network. The encoder, the decoder and the attention mechanism are jointly trained to maximize the conditional probability of a target sequence given a source sequence. Our experiments on different datasets show that the proposed encoder-decoder model is able to achieve significantly higher transliteration quality over traditional statistical models.
[ { "version": "v1", "created": "Wed, 14 Sep 2016 13:12:12 GMT" } ]
2016-09-15T00:00:00
[ [ "Jadidinejad", "Amir H.", "" ] ]
TITLE: Neural Machine Transliteration: Preliminary Results ABSTRACT: Machine transliteration is the process of automatically transforming the script of a word from a source language to a target language, while preserving pronunciation. Sequence to sequence learning has recently emerged as a new paradigm in supervised learning. In this paper a character-based encoder-decoder model has been proposed that consists of two Recurrent Neural Networks. The encoder is a Bidirectional recurrent neural network that encodes a sequence of symbols into a fixed-length vector representation, and the decoder generates the target sequence using an attention-based recurrent neural network. The encoder, the decoder and the attention mechanism are jointly trained to maximize the conditional probability of a target sequence given a source sequence. Our experiments on different datasets show that the proposed encoder-decoder model is able to achieve significantly higher transliteration quality over traditional statistical models.
no_new_dataset
0.947962
1609.04281
Ridho Reinanda
Ridho Reinanda, Edgar Meij, Maarten de Rijke
Document Filtering for Long-tail Entities
CIKM2016, Proceedings of the 25th ACM International Conference on Information and Knowledge Management. 2016
null
10.1145/2983323.2983728
null
cs.IR
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Filtering relevant documents with respect to entities is an essential task in the context of knowledge base construction and maintenance. It entails processing a time-ordered stream of documents that might be relevant to an entity in order to select only those that contain vital information. State-of-the-art approaches to document filtering for popular entities are entity-dependent: they rely on and are also trained on the specifics of differentiating features for each specific entity. Moreover, these approaches tend to use so-called extrinsic information such as Wikipedia page views and related entities which is typically only available only for popular head entities. Entity-dependent approaches based on such signals are therefore ill-suited as filtering methods for long-tail entities. In this paper we propose a document filtering method for long-tail entities that is entity-independent and thus also generalizes to unseen or rarely seen entities. It is based on intrinsic features, i.e., features that are derived from the documents in which the entities are mentioned. We propose a set of features that capture informativeness, entity-saliency, and timeliness. In particular, we introduce features based on entity aspect similarities, relation patterns, and temporal expressions and combine these with standard features for document filtering. Experiments following the TREC KBA 2014 setup on a publicly available dataset show that our model is able to improve the filtering performance for long-tail entities over several baselines. Results of applying the model to unseen entities are promising, indicating that the model is able to learn the general characteristics of a vital document. The overall performance across all entities---i.e., not just long-tail entities---improves upon the state-of-the-art without depending on any entity-specific training data.
[ { "version": "v1", "created": "Wed, 14 Sep 2016 14:09:20 GMT" } ]
2016-09-15T00:00:00
[ [ "Reinanda", "Ridho", "" ], [ "Meij", "Edgar", "" ], [ "de Rijke", "Maarten", "" ] ]
TITLE: Document Filtering for Long-tail Entities ABSTRACT: Filtering relevant documents with respect to entities is an essential task in the context of knowledge base construction and maintenance. It entails processing a time-ordered stream of documents that might be relevant to an entity in order to select only those that contain vital information. State-of-the-art approaches to document filtering for popular entities are entity-dependent: they rely on and are also trained on the specifics of differentiating features for each specific entity. Moreover, these approaches tend to use so-called extrinsic information such as Wikipedia page views and related entities which is typically only available only for popular head entities. Entity-dependent approaches based on such signals are therefore ill-suited as filtering methods for long-tail entities. In this paper we propose a document filtering method for long-tail entities that is entity-independent and thus also generalizes to unseen or rarely seen entities. It is based on intrinsic features, i.e., features that are derived from the documents in which the entities are mentioned. We propose a set of features that capture informativeness, entity-saliency, and timeliness. In particular, we introduce features based on entity aspect similarities, relation patterns, and temporal expressions and combine these with standard features for document filtering. Experiments following the TREC KBA 2014 setup on a publicly available dataset show that our model is able to improve the filtering performance for long-tail entities over several baselines. Results of applying the model to unseen entities are promising, indicating that the model is able to learn the general characteristics of a vital document. The overall performance across all entities---i.e., not just long-tail entities---improves upon the state-of-the-art without depending on any entity-specific training data.
no_new_dataset
0.953492
1609.04321
Luca Masera
Luca Masera, Enrico Blanzieri
Very Simple Classifier: a Concept Binary Classifier toInvestigate Features Based on Subsampling and Localility
null
null
null
null
cs.LG stat.ML
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We propose Very Simple Classifier (VSC) a novel method designed to incorporate the concepts of subsampling and locality in the definition of features to be used as the input of a perceptron. The rationale is that locality theoretically guarantees a bound on the generalization error. Each feature in VSC is a max-margin classifier built on randomly-selected pairs of samples. The locality in VSC is achieved by multiplying the value of the feature by a confidence measure that can be characterized in terms of the Chebichev inequality. The output of the layer is then fed in a output layer of neurons. The weights of the output layer are then determined by a regularized pseudoinverse. Extensive comparison of VSC against 9 competitors in the task of binary classification is carried out. Results on 22 benchmark datasets with fixed parameters show that VSC is competitive with the Multi Layer Perceptron (MLP) and outperforms the other competitors. An exploration of the parameter space shows VSC can outperform MLP.
[ { "version": "v1", "created": "Wed, 14 Sep 2016 15:51:46 GMT" } ]
2016-09-15T00:00:00
[ [ "Masera", "Luca", "" ], [ "Blanzieri", "Enrico", "" ] ]
TITLE: Very Simple Classifier: a Concept Binary Classifier toInvestigate Features Based on Subsampling and Localility ABSTRACT: We propose Very Simple Classifier (VSC) a novel method designed to incorporate the concepts of subsampling and locality in the definition of features to be used as the input of a perceptron. The rationale is that locality theoretically guarantees a bound on the generalization error. Each feature in VSC is a max-margin classifier built on randomly-selected pairs of samples. The locality in VSC is achieved by multiplying the value of the feature by a confidence measure that can be characterized in terms of the Chebichev inequality. The output of the layer is then fed in a output layer of neurons. The weights of the output layer are then determined by a regularized pseudoinverse. Extensive comparison of VSC against 9 competitors in the task of binary classification is carried out. Results on 22 benchmark datasets with fixed parameters show that VSC is competitive with the Multi Layer Perceptron (MLP) and outperforms the other competitors. An exploration of the parameter space shows VSC can outperform MLP.
no_new_dataset
0.944842
1512.04103
Yaser Souri
Yaser Souri, Erfan Noury, Ehsan Adeli
Deep Relative Attributes
ACCV 2016
null
null
null
cs.CV
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Visual attributes are great means of describing images or scenes, in a way both humans and computers understand. In order to establish a correspondence between images and to be able to compare the strength of each property between images, relative attributes were introduced. However, since their introduction, hand-crafted and engineered features were used to learn increasingly complex models for the problem of relative attributes. This limits the applicability of those methods for more realistic cases. We introduce a deep neural network architecture for the task of relative attribute prediction. A convolutional neural network (ConvNet) is adopted to learn the features by including an additional layer (ranking layer) that learns to rank the images based on these features. We adopt an appropriate ranking loss to train the whole network in an end-to-end fashion. Our proposed method outperforms the baseline and state-of-the-art methods in relative attribute prediction on various coarse and fine-grained datasets. Our qualitative results along with the visualization of the saliency maps show that the network is able to learn effective features for each specific attribute. Source code of the proposed method is available at https://github.com/yassersouri/ghiaseddin.
[ { "version": "v1", "created": "Sun, 13 Dec 2015 19:10:16 GMT" }, { "version": "v2", "created": "Tue, 13 Sep 2016 08:21:43 GMT" } ]
2016-09-14T00:00:00
[ [ "Souri", "Yaser", "" ], [ "Noury", "Erfan", "" ], [ "Adeli", "Ehsan", "" ] ]
TITLE: Deep Relative Attributes ABSTRACT: Visual attributes are great means of describing images or scenes, in a way both humans and computers understand. In order to establish a correspondence between images and to be able to compare the strength of each property between images, relative attributes were introduced. However, since their introduction, hand-crafted and engineered features were used to learn increasingly complex models for the problem of relative attributes. This limits the applicability of those methods for more realistic cases. We introduce a deep neural network architecture for the task of relative attribute prediction. A convolutional neural network (ConvNet) is adopted to learn the features by including an additional layer (ranking layer) that learns to rank the images based on these features. We adopt an appropriate ranking loss to train the whole network in an end-to-end fashion. Our proposed method outperforms the baseline and state-of-the-art methods in relative attribute prediction on various coarse and fine-grained datasets. Our qualitative results along with the visualization of the saliency maps show that the network is able to learn effective features for each specific attribute. Source code of the proposed method is available at https://github.com/yassersouri/ghiaseddin.
no_new_dataset
0.947186
1602.00828
Hossein Rahmani
Hossein Rahmani and Ajmal Mian and Mubarak Shah
Learning a Deep Model for Human Action Recognition from Novel Viewpoints
null
Phys. Rev. D 94, 065007 (2016)
10.1103/PhysRevD.94.065007
null
cs.CV
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Recognizing human actions from unknown and unseen (novel) views is a challenging problem. We propose a Robust Non-Linear Knowledge Transfer Model (R-NKTM) for human action recognition from novel views. The proposed R-NKTM is a deep fully-connected neural network that transfers knowledge of human actions from any unknown view to a shared high-level virtual view by finding a non-linear virtual path that connects the views. The R-NKTM is learned from dense trajectories of synthetic 3D human models fitted to real motion capture data and generalizes to real videos of human actions. The strength of our technique is that we learn a single R-NKTM for all actions and all viewpoints for knowledge transfer of any real human action video without the need for re-training or fine-tuning the model. Thus, R-NKTM can efficiently scale to incorporate new action classes. R-NKTM is learned with dummy labels and does not require knowledge of the camera viewpoint at any stage. Experiments on three benchmark cross-view human action datasets show that our method outperforms existing state-of-the-art.
[ { "version": "v1", "created": "Tue, 2 Feb 2016 08:42:44 GMT" } ]
2016-09-14T00:00:00
[ [ "Rahmani", "Hossein", "" ], [ "Mian", "Ajmal", "" ], [ "Shah", "Mubarak", "" ] ]
TITLE: Learning a Deep Model for Human Action Recognition from Novel Viewpoints ABSTRACT: Recognizing human actions from unknown and unseen (novel) views is a challenging problem. We propose a Robust Non-Linear Knowledge Transfer Model (R-NKTM) for human action recognition from novel views. The proposed R-NKTM is a deep fully-connected neural network that transfers knowledge of human actions from any unknown view to a shared high-level virtual view by finding a non-linear virtual path that connects the views. The R-NKTM is learned from dense trajectories of synthetic 3D human models fitted to real motion capture data and generalizes to real videos of human actions. The strength of our technique is that we learn a single R-NKTM for all actions and all viewpoints for knowledge transfer of any real human action video without the need for re-training or fine-tuning the model. Thus, R-NKTM can efficiently scale to incorporate new action classes. R-NKTM is learned with dummy labels and does not require knowledge of the camera viewpoint at any stage. Experiments on three benchmark cross-view human action datasets show that our method outperforms existing state-of-the-art.
no_new_dataset
0.94474
1606.07674
Yin Zheng
Yin Zheng, Cailiang Liu, Bangsheng Tang, Hanning Zhou
Neural Autoregressive Collaborative Filtering for Implicit Feedback
5 pages, 2 figures, accepted by DLRS2016 http://dlrs-workshop.org/
null
10.1145/2988450.2988453
null
cs.IR
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
This paper proposes implicit CF-NADE, a neural autoregressive model for collaborative filtering tasks using implicit feedback ( e.g. click, watch, browse behaviors). We first convert a users implicit feedback into a like vector and a confidence vector, and then model the probability of the like vector, weighted by the confidence vector. The training objective of implicit CF-NADE is to maximize a weighted negative log-likelihood. We test the performance of implicit CF-NADE on a dataset collected from a popular digital TV streaming service. More specifically, in the experiments, we describe how to convert watch counts into implicit relative rating, and feed into implicit CF-NADE. Then we compare the performance of implicit CF-NADE model with the popular implicit matrix factorization approach. Experimental results show that implicit CF-NADE significantly outperforms the baseline.
[ { "version": "v1", "created": "Fri, 24 Jun 2016 13:10:50 GMT" }, { "version": "v2", "created": "Tue, 13 Sep 2016 03:11:12 GMT" } ]
2016-09-14T00:00:00
[ [ "Zheng", "Yin", "" ], [ "Liu", "Cailiang", "" ], [ "Tang", "Bangsheng", "" ], [ "Zhou", "Hanning", "" ] ]
TITLE: Neural Autoregressive Collaborative Filtering for Implicit Feedback ABSTRACT: This paper proposes implicit CF-NADE, a neural autoregressive model for collaborative filtering tasks using implicit feedback ( e.g. click, watch, browse behaviors). We first convert a users implicit feedback into a like vector and a confidence vector, and then model the probability of the like vector, weighted by the confidence vector. The training objective of implicit CF-NADE is to maximize a weighted negative log-likelihood. We test the performance of implicit CF-NADE on a dataset collected from a popular digital TV streaming service. More specifically, in the experiments, we describe how to convert watch counts into implicit relative rating, and feed into implicit CF-NADE. Then we compare the performance of implicit CF-NADE model with the popular implicit matrix factorization approach. Experimental results show that implicit CF-NADE significantly outperforms the baseline.
no_new_dataset
0.950686
1607.08206
Cheng Zhang
Cheng Zhang, Hedvig Kjellstrom, Carl Henrik Ek, Bo C. Bertilson
Diagnostic Prediction Using Discomfort Drawings with IBTM
Presented at 2016 Machine Learning and Healthcare Conference (MLHC 2016), Los Angeles, CA
null
null
null
cs.LG
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
In this paper, we explore the possibility to apply machine learning to make diagnostic predictions using discomfort drawings. A discomfort drawing is an intuitive way for patients to express discomfort and pain related symptoms. These drawings have proven to be an effective method to collect patient data and make diagnostic decisions in real-life practice. A dataset from real-world patient cases is collected for which medical experts provide diagnostic labels. Next, we use a factorized multimodal topic model, Inter-Battery Topic Model (IBTM), to train a system that can make diagnostic predictions given an unseen discomfort drawing. The number of output diagnostic labels is determined by using mean-shift clustering on the discomfort drawing. Experimental results show reasonable predictions of diagnostic labels given an unseen discomfort drawing. Additionally, we generate synthetic discomfort drawings with IBTM given a diagnostic label, which results in typical cases of symptoms. The positive result indicates a significant potential of machine learning to be used for parts of the pain diagnostic process and to be a decision support system for physicians and other health care personnel.
[ { "version": "v1", "created": "Wed, 27 Jul 2016 18:20:01 GMT" }, { "version": "v2", "created": "Tue, 13 Sep 2016 16:26:41 GMT" } ]
2016-09-14T00:00:00
[ [ "Zhang", "Cheng", "" ], [ "Kjellstrom", "Hedvig", "" ], [ "Ek", "Carl Henrik", "" ], [ "Bertilson", "Bo C.", "" ] ]
TITLE: Diagnostic Prediction Using Discomfort Drawings with IBTM ABSTRACT: In this paper, we explore the possibility to apply machine learning to make diagnostic predictions using discomfort drawings. A discomfort drawing is an intuitive way for patients to express discomfort and pain related symptoms. These drawings have proven to be an effective method to collect patient data and make diagnostic decisions in real-life practice. A dataset from real-world patient cases is collected for which medical experts provide diagnostic labels. Next, we use a factorized multimodal topic model, Inter-Battery Topic Model (IBTM), to train a system that can make diagnostic predictions given an unseen discomfort drawing. The number of output diagnostic labels is determined by using mean-shift clustering on the discomfort drawing. Experimental results show reasonable predictions of diagnostic labels given an unseen discomfort drawing. Additionally, we generate synthetic discomfort drawings with IBTM given a diagnostic label, which results in typical cases of symptoms. The positive result indicates a significant potential of machine learning to be used for parts of the pain diagnostic process and to be a decision support system for physicians and other health care personnel.
no_new_dataset
0.943348
1609.03540
Babak Salimi
Babak Salimi, Dan Suciu
ZaliQL: A SQL-Based Framework for Drawing Causal Inference from Big Data
null
null
null
null
cs.DB cs.AI cs.LG cs.PF
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Causal inference from observational data is a subject of active research and development in statistics and computer science. Many toolkits have been developed for this purpose that depends on statistical software. However, these toolkits do not scale to large datasets. In this paper we describe a suite of techniques for expressing causal inference tasks from observational data in SQL. This suite supports the state-of-the-art methods for causal inference and run at scale within a database engine. In addition, we introduce several optimization techniques that significantly speedup causal inference, both in the online and offline setting. We evaluate the quality and performance of our techniques by experiments of real datasets.
[ { "version": "v1", "created": "Mon, 12 Sep 2016 19:24:14 GMT" }, { "version": "v2", "created": "Tue, 13 Sep 2016 01:59:05 GMT" } ]
2016-09-14T00:00:00
[ [ "Salimi", "Babak", "" ], [ "Suciu", "Dan", "" ] ]
TITLE: ZaliQL: A SQL-Based Framework for Drawing Causal Inference from Big Data ABSTRACT: Causal inference from observational data is a subject of active research and development in statistics and computer science. Many toolkits have been developed for this purpose that depends on statistical software. However, these toolkits do not scale to large datasets. In this paper we describe a suite of techniques for expressing causal inference tasks from observational data in SQL. This suite supports the state-of-the-art methods for causal inference and run at scale within a database engine. In addition, we introduce several optimization techniques that significantly speedup causal inference, both in the online and offline setting. We evaluate the quality and performance of our techniques by experiments of real datasets.
no_new_dataset
0.945601
1609.03666
S\'ebastien Arnold
S\'ebastien Arnold
A Greedy Algorithm to Cluster Specialists
null
null
null
null
cs.LG stat.ML
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Several recent deep neural networks experiments leverage the generalist-specialist paradigm for classification. However, no formal study compared the performance of different clustering algorithms for class assignment. In this paper we perform such a study, suggest slight modifications to the clustering procedures, and propose a novel algorithm designed to optimize the performance of of the specialist-generalist classification system. Our experiments on the CIFAR-10 and CIFAR-100 datasets allow us to investigate situations for varying number of classes on similar data. We find that our \emph{greedy pairs} clustering algorithm consistently outperforms other alternatives, while the choice of the confusion matrix has little impact on the final performance.
[ { "version": "v1", "created": "Tue, 13 Sep 2016 03:26:42 GMT" } ]
2016-09-14T00:00:00
[ [ "Arnold", "Sébastien", "" ] ]
TITLE: A Greedy Algorithm to Cluster Specialists ABSTRACT: Several recent deep neural networks experiments leverage the generalist-specialist paradigm for classification. However, no formal study compared the performance of different clustering algorithms for class assignment. In this paper we perform such a study, suggest slight modifications to the clustering procedures, and propose a novel algorithm designed to optimize the performance of of the specialist-generalist classification system. Our experiments on the CIFAR-10 and CIFAR-100 datasets allow us to investigate situations for varying number of classes on similar data. We find that our \emph{greedy pairs} clustering algorithm consistently outperforms other alternatives, while the choice of the confusion matrix has little impact on the final performance.
no_new_dataset
0.95253
1609.03795
Domen Tabernik
Domen Tabernik, Matej Kristan, Jeremy L. Wyatt, and Ale\v{s} Leonardis
Towards Deep Compositional Networks
Published in proceedings of 23th International Conference on Pattern Recognition (ICPR 2016)
null
null
null
cs.CV
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Hierarchical feature learning based on convolutional neural networks (CNN) has recently shown significant potential in various computer vision tasks. While allowing high-quality discriminative feature learning, the downside of CNNs is the lack of explicit structure in features, which often leads to overfitting, absence of reconstruction from partial observations and limited generative abilities. Explicit structure is inherent in hierarchical compositional models, however, these lack the ability to optimize a well-defined cost function. We propose a novel analytic model of a basic unit in a layered hierarchical model with both explicit compositional structure and a well-defined discriminative cost function. Our experiments on two datasets show that the proposed compositional model performs on a par with standard CNNs on discriminative tasks, while, due to explicit modeling of the structure in the feature units, affording a straight-forward visualization of parts and faster inference due to separability of the units. Actions
[ { "version": "v1", "created": "Tue, 13 Sep 2016 12:31:29 GMT" } ]
2016-09-14T00:00:00
[ [ "Tabernik", "Domen", "" ], [ "Kristan", "Matej", "" ], [ "Wyatt", "Jeremy L.", "" ], [ "Leonardis", "Aleš", "" ] ]
TITLE: Towards Deep Compositional Networks ABSTRACT: Hierarchical feature learning based on convolutional neural networks (CNN) has recently shown significant potential in various computer vision tasks. While allowing high-quality discriminative feature learning, the downside of CNNs is the lack of explicit structure in features, which often leads to overfitting, absence of reconstruction from partial observations and limited generative abilities. Explicit structure is inherent in hierarchical compositional models, however, these lack the ability to optimize a well-defined cost function. We propose a novel analytic model of a basic unit in a layered hierarchical model with both explicit compositional structure and a well-defined discriminative cost function. Our experiments on two datasets show that the proposed compositional model performs on a par with standard CNNs on discriminative tasks, while, due to explicit modeling of the structure in the feature units, affording a straight-forward visualization of parts and faster inference due to separability of the units. Actions
no_new_dataset
0.949342
1609.03894
Francisco Massa
Francisco Massa, Renaud Marlet, Mathieu Aubry
Crafting a multi-task CNN for viewpoint estimation
To appear in BMVC 2016
null
null
null
cs.CV cs.LG cs.NE
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Convolutional Neural Networks (CNNs) were recently shown to provide state-of-the-art results for object category viewpoint estimation. However different ways of formulating this problem have been proposed and the competing approaches have been explored with very different design choices. This paper presents a comparison of these approaches in a unified setting as well as a detailed analysis of the key factors that impact performance. Followingly, we present a new joint training method with the detection task and demonstrate its benefit. We also highlight the superiority of classification approaches over regression approaches, quantify the benefits of deeper architectures and extended training data, and demonstrate that synthetic data is beneficial even when using ImageNet training data. By combining all these elements, we demonstrate an improvement of approximately 5% mAVP over previous state-of-the-art results on the Pascal3D+ dataset. In particular for their most challenging 24 view classification task we improve the results from 31.1% to 36.1% mAVP.
[ { "version": "v1", "created": "Tue, 13 Sep 2016 15:19:38 GMT" } ]
2016-09-14T00:00:00
[ [ "Massa", "Francisco", "" ], [ "Marlet", "Renaud", "" ], [ "Aubry", "Mathieu", "" ] ]
TITLE: Crafting a multi-task CNN for viewpoint estimation ABSTRACT: Convolutional Neural Networks (CNNs) were recently shown to provide state-of-the-art results for object category viewpoint estimation. However different ways of formulating this problem have been proposed and the competing approaches have been explored with very different design choices. This paper presents a comparison of these approaches in a unified setting as well as a detailed analysis of the key factors that impact performance. Followingly, we present a new joint training method with the detection task and demonstrate its benefit. We also highlight the superiority of classification approaches over regression approaches, quantify the benefits of deeper architectures and extended training data, and demonstrate that synthetic data is beneficial even when using ImageNet training data. By combining all these elements, we demonstrate an improvement of approximately 5% mAVP over previous state-of-the-art results on the Pascal3D+ dataset. In particular for their most challenging 24 view classification task we improve the results from 31.1% to 36.1% mAVP.
no_new_dataset
0.947039
1609.03976
Ozan \c{C}a\u{g}layan
Ozan Caglayan, Lo\"ic Barrault, Fethi Bougares
Multimodal Attention for Neural Machine Translation
10 pages, under review COLING 2016
null
null
null
cs.CL cs.NE
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The attention mechanism is an important part of the neural machine translation (NMT) where it was reported to produce richer source representation compared to fixed-length encoding sequence-to-sequence models. Recently, the effectiveness of attention has also been explored in the context of image captioning. In this work, we assess the feasibility of a multimodal attention mechanism that simultaneously focus over an image and its natural language description for generating a description in another language. We train several variants of our proposed attention mechanism on the Multi30k multilingual image captioning dataset. We show that a dedicated attention for each modality achieves up to 1.6 points in BLEU and METEOR compared to a textual NMT baseline.
[ { "version": "v1", "created": "Tue, 13 Sep 2016 18:46:03 GMT" } ]
2016-09-14T00:00:00
[ [ "Caglayan", "Ozan", "" ], [ "Barrault", "Loïc", "" ], [ "Bougares", "Fethi", "" ] ]
TITLE: Multimodal Attention for Neural Machine Translation ABSTRACT: The attention mechanism is an important part of the neural machine translation (NMT) where it was reported to produce richer source representation compared to fixed-length encoding sequence-to-sequence models. Recently, the effectiveness of attention has also been explored in the context of image captioning. In this work, we assess the feasibility of a multimodal attention mechanism that simultaneously focus over an image and its natural language description for generating a description in another language. We train several variants of our proposed attention mechanism on the Multi30k multilingual image captioning dataset. We show that a dedicated attention for each modality achieves up to 1.6 points in BLEU and METEOR compared to a textual NMT baseline.
no_new_dataset
0.950319
1504.04785
Mahdi Boloursaz Mashhadi
Mahdi Boloursaz Mashhadi, Ehsan Asadi, Mohsen Eskandari, Shahrzad Kiani, and Farrokh Marvasti
Heart Rate Tracking using Wrist-Type Photoplethysmographic (PPG) Signals during Physical Exercise with Simultaneous Accelerometry
Accepted for publication in IEEE Signal Processing Letters
null
10.1109/LSP.2015.2509868
null
cs.IT math.IT
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
This paper considers the problem of casual heart rate tracking during intensive physical exercise using simultaneous 2 channel photoplethysmographic (PPG) and 3 dimensional (3D) acceleration signals recorded from wrist. This is a challenging problem because the PPG signals recorded from wrist during exercise are contaminated by strong Motion Artifacts (MAs). In this work, a novel algorithm is proposed which consists of two main steps of MA Cancellation and Spectral Analysis. The MA cancellation step cleanses the MA-contaminated PPG signals utilizing the acceleration data and the spectral analysis step estimates a higher resolution spectrum of the signal and selects the spectral peaks corresponding to HR. Experimental results on datasets recorded from 12 subjects during fast running at the peak speed of 15 km/hour showed that the proposed algorithm achieves an average absolute error of 1.25 beat per minute (BPM). These experimental results also confirm that the proposed algorithm keeps high estimation accuracies even in strong MA conditions.
[ { "version": "v1", "created": "Sun, 19 Apr 2015 03:29:15 GMT" }, { "version": "v2", "created": "Mon, 12 Sep 2016 19:28:32 GMT" } ]
2016-09-13T00:00:00
[ [ "Mashhadi", "Mahdi Boloursaz", "" ], [ "Asadi", "Ehsan", "" ], [ "Eskandari", "Mohsen", "" ], [ "Kiani", "Shahrzad", "" ], [ "Marvasti", "Farrokh", "" ] ]
TITLE: Heart Rate Tracking using Wrist-Type Photoplethysmographic (PPG) Signals during Physical Exercise with Simultaneous Accelerometry ABSTRACT: This paper considers the problem of casual heart rate tracking during intensive physical exercise using simultaneous 2 channel photoplethysmographic (PPG) and 3 dimensional (3D) acceleration signals recorded from wrist. This is a challenging problem because the PPG signals recorded from wrist during exercise are contaminated by strong Motion Artifacts (MAs). In this work, a novel algorithm is proposed which consists of two main steps of MA Cancellation and Spectral Analysis. The MA cancellation step cleanses the MA-contaminated PPG signals utilizing the acceleration data and the spectral analysis step estimates a higher resolution spectrum of the signal and selects the spectral peaks corresponding to HR. Experimental results on datasets recorded from 12 subjects during fast running at the peak speed of 15 km/hour showed that the proposed algorithm achieves an average absolute error of 1.25 beat per minute (BPM). These experimental results also confirm that the proposed algorithm keeps high estimation accuracies even in strong MA conditions.
no_new_dataset
0.939692
1604.06486
Saeed Reza Kheradpisheh
Saeed Reza Kheradpisheh, Masoud Ghodrati, Mohammad Ganjtabesh, Timoth\'ee Masquelier
Humans and deep networks largely agree on which kinds of variation make object recognition harder
null
Frontiers in Computational Neuroscience (2016) 10:92
10.3389/fncom.2016.00092
null
cs.CV q-bio.NC
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
View-invariant object recognition is a challenging problem, which has attracted much attention among the psychology, neuroscience, and computer vision communities. Humans are notoriously good at it, even if some variations are presumably more difficult to handle than others (e.g. 3D rotations). Humans are thought to solve the problem through hierarchical processing along the ventral stream, which progressively extracts more and more invariant visual features. This feed-forward architecture has inspired a new generation of bio-inspired computer vision systems called deep convolutional neural networks (DCNN), which are currently the best algorithms for object recognition in natural images. Here, for the first time, we systematically compared human feed-forward vision and DCNNs at view-invariant object recognition using the same images and controlling for both the kinds of transformation as well as their magnitude. We used four object categories and images were rendered from 3D computer models. In total, 89 human subjects participated in 10 experiments in which they had to discriminate between two or four categories after rapid presentation with backward masking. We also tested two recent DCNNs on the same tasks. We found that humans and DCNNs largely agreed on the relative difficulties of each kind of variation: rotation in depth is by far the hardest transformation to handle, followed by scale, then rotation in plane, and finally position. This suggests that humans recognize objects mainly through 2D template matching, rather than by constructing 3D object models, and that DCNNs are not too unreasonable models of human feed-forward vision. Also, our results show that the variation levels in rotation in depth and scale strongly modulate both humans' and DCNNs' recognition performances. We thus argue that these variations should be controlled in the image datasets used in vision research.
[ { "version": "v1", "created": "Thu, 21 Apr 2016 20:53:00 GMT" } ]
2016-09-13T00:00:00
[ [ "Kheradpisheh", "Saeed Reza", "" ], [ "Ghodrati", "Masoud", "" ], [ "Ganjtabesh", "Mohammad", "" ], [ "Masquelier", "Timothée", "" ] ]
TITLE: Humans and deep networks largely agree on which kinds of variation make object recognition harder ABSTRACT: View-invariant object recognition is a challenging problem, which has attracted much attention among the psychology, neuroscience, and computer vision communities. Humans are notoriously good at it, even if some variations are presumably more difficult to handle than others (e.g. 3D rotations). Humans are thought to solve the problem through hierarchical processing along the ventral stream, which progressively extracts more and more invariant visual features. This feed-forward architecture has inspired a new generation of bio-inspired computer vision systems called deep convolutional neural networks (DCNN), which are currently the best algorithms for object recognition in natural images. Here, for the first time, we systematically compared human feed-forward vision and DCNNs at view-invariant object recognition using the same images and controlling for both the kinds of transformation as well as their magnitude. We used four object categories and images were rendered from 3D computer models. In total, 89 human subjects participated in 10 experiments in which they had to discriminate between two or four categories after rapid presentation with backward masking. We also tested two recent DCNNs on the same tasks. We found that humans and DCNNs largely agreed on the relative difficulties of each kind of variation: rotation in depth is by far the hardest transformation to handle, followed by scale, then rotation in plane, and finally position. This suggests that humans recognize objects mainly through 2D template matching, rather than by constructing 3D object models, and that DCNNs are not too unreasonable models of human feed-forward vision. Also, our results show that the variation levels in rotation in depth and scale strongly modulate both humans' and DCNNs' recognition performances. We thus argue that these variations should be controlled in the image datasets used in vision research.
no_new_dataset
0.9462
1606.03152
Mehdi Fatemi
Mehdi Fatemi, Layla El Asri, Hannes Schulz, Jing He, Kaheer Suleman
Policy Networks with Two-Stage Training for Dialogue Systems
SIGDial 2016 (Submitted: May 2016; Accepted: Jun 30, 2016)
Proceedings of the SIGDIAL 2016 Conference, pages 101--110, Los Angeles, USA, 13-15 September 2016. Association for Computational Linguistics
null
null
cs.CL cs.AI
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
In this paper, we propose to use deep policy networks which are trained with an advantage actor-critic method for statistically optimised dialogue systems. First, we show that, on summary state and action spaces, deep Reinforcement Learning (RL) outperforms Gaussian Processes methods. Summary state and action spaces lead to good performance but require pre-engineering effort, RL knowledge, and domain expertise. In order to remove the need to define such summary spaces, we show that deep RL can also be trained efficiently on the original state and action spaces. Dialogue systems based on partially observable Markov decision processes are known to require many dialogues to train, which makes them unappealing for practical deployment. We show that a deep RL method based on an actor-critic architecture can exploit a small amount of data very efficiently. Indeed, with only a few hundred dialogues collected with a handcrafted policy, the actor-critic deep learner is considerably bootstrapped from a combination of supervised and batch RL. In addition, convergence to an optimal policy is significantly sped up compared to other deep RL methods initialized on the data with batch RL. All experiments are performed on a restaurant domain derived from the Dialogue State Tracking Challenge 2 (DSTC2) dataset.
[ { "version": "v1", "created": "Fri, 10 Jun 2016 01:02:19 GMT" }, { "version": "v2", "created": "Tue, 19 Jul 2016 16:20:18 GMT" }, { "version": "v3", "created": "Sat, 20 Aug 2016 21:20:21 GMT" }, { "version": "v4", "created": "Mon, 12 Sep 2016 16:23:42 GMT" } ]
2016-09-13T00:00:00
[ [ "Fatemi", "Mehdi", "" ], [ "Asri", "Layla El", "" ], [ "Schulz", "Hannes", "" ], [ "He", "Jing", "" ], [ "Suleman", "Kaheer", "" ] ]
TITLE: Policy Networks with Two-Stage Training for Dialogue Systems ABSTRACT: In this paper, we propose to use deep policy networks which are trained with an advantage actor-critic method for statistically optimised dialogue systems. First, we show that, on summary state and action spaces, deep Reinforcement Learning (RL) outperforms Gaussian Processes methods. Summary state and action spaces lead to good performance but require pre-engineering effort, RL knowledge, and domain expertise. In order to remove the need to define such summary spaces, we show that deep RL can also be trained efficiently on the original state and action spaces. Dialogue systems based on partially observable Markov decision processes are known to require many dialogues to train, which makes them unappealing for practical deployment. We show that a deep RL method based on an actor-critic architecture can exploit a small amount of data very efficiently. Indeed, with only a few hundred dialogues collected with a handcrafted policy, the actor-critic deep learner is considerably bootstrapped from a combination of supervised and batch RL. In addition, convergence to an optimal policy is significantly sped up compared to other deep RL methods initialized on the data with batch RL. All experiments are performed on a restaurant domain derived from the Dialogue State Tracking Challenge 2 (DSTC2) dataset.
no_new_dataset
0.943348
1607.01845
Agustin Indaco
Agustin Indaco and Lev Manovich
Urban Social Media Inequality: Definition, Measurements, and Application
53 pages, 11 figures, 3 tables
null
null
null
cs.SI physics.soc-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Social media content shared today in cities, such as Instagram images, their tags and descriptions, is the key form of contemporary city life. It tells people where activities and locations that interest them are and it allows them to share their urban experiences and self-representations. Therefore, any analysis of urban structures and cultures needs to consider social media activity. In our paper, we introduce the novel concept of social media inequality. This concept allows us to quantitatively compare patterns in social media activities between parts of a city, a number of cities, or any other spatial areas. We define this concept using an analogy with the concept of economic inequality. Economic inequality indicates how some economic characteristics or material resources, such as income, wealth or consumption are distributed in a city, country or between countries. Accordingly, we can define social media inequality as the measure of the distribution of characteristics from social media content shared in a particular geographic area or between areas. An example of such characteristics is the number of photos shared by all users of a social network such as Instagram in a given city or city area, or the content of these photos. We propose that the standard inequality measures used in other disciplines, such as the Gini coefficient, can also be used to characterize social media inequality. To test our ideas, we use a dataset of 7,442,454 public geo-coded Instagram images shared in Manhattan during five months (March-July) in 2014, and also selected data for 287 Census tracts in Manhattan. We compare patterns in Instagram sharing for locals and for visitors for all tracts, and also for hours in a 24-hour cycle. We also look at relations between social media inequality and socio-economic inequality using selected indicators for Census tracts.
[ { "version": "v1", "created": "Thu, 7 Jul 2016 00:43:25 GMT" }, { "version": "v2", "created": "Sun, 11 Sep 2016 20:45:35 GMT" } ]
2016-09-13T00:00:00
[ [ "Indaco", "Agustin", "" ], [ "Manovich", "Lev", "" ] ]
TITLE: Urban Social Media Inequality: Definition, Measurements, and Application ABSTRACT: Social media content shared today in cities, such as Instagram images, their tags and descriptions, is the key form of contemporary city life. It tells people where activities and locations that interest them are and it allows them to share their urban experiences and self-representations. Therefore, any analysis of urban structures and cultures needs to consider social media activity. In our paper, we introduce the novel concept of social media inequality. This concept allows us to quantitatively compare patterns in social media activities between parts of a city, a number of cities, or any other spatial areas. We define this concept using an analogy with the concept of economic inequality. Economic inequality indicates how some economic characteristics or material resources, such as income, wealth or consumption are distributed in a city, country or between countries. Accordingly, we can define social media inequality as the measure of the distribution of characteristics from social media content shared in a particular geographic area or between areas. An example of such characteristics is the number of photos shared by all users of a social network such as Instagram in a given city or city area, or the content of these photos. We propose that the standard inequality measures used in other disciplines, such as the Gini coefficient, can also be used to characterize social media inequality. To test our ideas, we use a dataset of 7,442,454 public geo-coded Instagram images shared in Manhattan during five months (March-July) in 2014, and also selected data for 287 Census tracts in Manhattan. We compare patterns in Instagram sharing for locals and for visitors for all tracts, and also for hours in a 24-hour cycle. We also look at relations between social media inequality and socio-economic inequality using selected indicators for Census tracts.
no_new_dataset
0.730819
1608.01769
Abhimanyu Dubey
Abhimanyu Dubey, Nikhil Naik, Devi Parikh, Ramesh Raskar and C\'esar A. Hidalgo
Deep Learning the City : Quantifying Urban Perception At A Global Scale
23 pages, 8 figures. Accepted to the European Conference on Computer Vision (ECCV), 2016
null
null
null
cs.CV
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Computer vision methods that quantify the perception of urban environment are increasingly being used to study the relationship between a city's physical appearance and the behavior and health of its residents. Yet, the throughput of current methods is too limited to quantify the perception of cities across the world. To tackle this challenge, we introduce a new crowdsourced dataset containing 110,988 images from 56 cities, and 1,170,000 pairwise comparisons provided by 81,630 online volunteers along six perceptual attributes: safe, lively, boring, wealthy, depressing, and beautiful. Using this data, we train a Siamese-like convolutional neural architecture, which learns from a joint classification and ranking loss, to predict human judgments of pairwise image comparisons. Our results show that crowdsourcing combined with neural networks can produce urban perception data at the global scale.
[ { "version": "v1", "created": "Fri, 5 Aug 2016 05:58:35 GMT" }, { "version": "v2", "created": "Mon, 12 Sep 2016 18:48:37 GMT" } ]
2016-09-13T00:00:00
[ [ "Dubey", "Abhimanyu", "" ], [ "Naik", "Nikhil", "" ], [ "Parikh", "Devi", "" ], [ "Raskar", "Ramesh", "" ], [ "Hidalgo", "César A.", "" ] ]
TITLE: Deep Learning the City : Quantifying Urban Perception At A Global Scale ABSTRACT: Computer vision methods that quantify the perception of urban environment are increasingly being used to study the relationship between a city's physical appearance and the behavior and health of its residents. Yet, the throughput of current methods is too limited to quantify the perception of cities across the world. To tackle this challenge, we introduce a new crowdsourced dataset containing 110,988 images from 56 cities, and 1,170,000 pairwise comparisons provided by 81,630 online volunteers along six perceptual attributes: safe, lively, boring, wealthy, depressing, and beautiful. Using this data, we train a Siamese-like convolutional neural architecture, which learns from a joint classification and ranking loss, to predict human judgments of pairwise image comparisons. Our results show that crowdsourcing combined with neural networks can produce urban perception data at the global scale.
new_dataset
0.963231
1609.02947
Nhien-An Le-Khac
Andree Linke, Nhien-An Le-Khac
Control Flow Change in Assembly as a Classifier in Malware Analysis
null
null
null
null
cs.CR
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
As currently classical malware detection methods based on signatures fail to detect new malware, they are not always efficient with new obfuscation techniques. Besides, new malware is easily created and old malware can be recoded to produce new one. Therefore, classical Antivirus becomes consistently less effective in dealing with those new threats. Also malware gets hand tailored to bypass network security and Antivirus. But as analysts do not have enough time to dissect suspected malware by hand, automated approaches have been developed. To cope with the mass of new malware, statistical and machine learning methods proved to be a good approach classifying programs, especially when using multiple approaches together to provide a likelihood of software being malicious. In normal approach, some steps have been taken, mostly by analyzing the opcodes or mnemonics of disassembly and their distribution. In this paper, we focus on the control flow change (CFC) itself and finding out if it is significant to detect malware. In the scope of this work, only relative control flow changes are contemplated, as these are easier to extract from the first chosen disassembler library and are within a range of 256 addresses. These features are analyzed as a raw feature, as n-grams of length 2, 4 and 6 and the even more abstract feature of the occurrences of the n-grams is used. Statistical methods were used as well as the Naive-Bayes algorithm to find out if there is significant data in CFC. We also test our approach with real-world datasets.
[ { "version": "v1", "created": "Fri, 9 Sep 2016 21:21:14 GMT" } ]
2016-09-13T00:00:00
[ [ "Linke", "Andree", "" ], [ "Le-Khac", "Nhien-An", "" ] ]
TITLE: Control Flow Change in Assembly as a Classifier in Malware Analysis ABSTRACT: As currently classical malware detection methods based on signatures fail to detect new malware, they are not always efficient with new obfuscation techniques. Besides, new malware is easily created and old malware can be recoded to produce new one. Therefore, classical Antivirus becomes consistently less effective in dealing with those new threats. Also malware gets hand tailored to bypass network security and Antivirus. But as analysts do not have enough time to dissect suspected malware by hand, automated approaches have been developed. To cope with the mass of new malware, statistical and machine learning methods proved to be a good approach classifying programs, especially when using multiple approaches together to provide a likelihood of software being malicious. In normal approach, some steps have been taken, mostly by analyzing the opcodes or mnemonics of disassembly and their distribution. In this paper, we focus on the control flow change (CFC) itself and finding out if it is significant to detect malware. In the scope of this work, only relative control flow changes are contemplated, as these are easier to extract from the first chosen disassembler library and are within a range of 256 addresses. These features are analyzed as a raw feature, as n-grams of length 2, 4 and 6 and the even more abstract feature of the occurrences of the n-grams is used. Statistical methods were used as well as the Naive-Bayes algorithm to find out if there is significant data in CFC. We also test our approach with real-world datasets.
no_new_dataset
0.943086
1609.02948
Ruichi Yu
Ruichi Yu, Xi Chen, Vlad I. Morariu, Larry S. Davis
The Role of Context Selection in Object Detection
null
null
null
null
cs.CV
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We investigate the reasons why context in object detection has limited utility by isolating and evaluating the predictive power of different context cues under ideal conditions in which context provided by an oracle. Based on this study, we propose a region-based context re-scoring method with dynamic context selection to remove noise and emphasize informative context. We introduce latent indicator variables to select (or ignore) potential contextual regions, and learn the selection strategy with latent-SVM. We conduct experiments to evaluate the performance of the proposed context selection method on the SUN RGB-D dataset. The method achieves a significant improvement in terms of mean average precision (mAP), compared with both appearance based detectors and a conventional context model without the selection scheme.
[ { "version": "v1", "created": "Fri, 9 Sep 2016 21:30:14 GMT" } ]
2016-09-13T00:00:00
[ [ "Yu", "Ruichi", "" ], [ "Chen", "Xi", "" ], [ "Morariu", "Vlad I.", "" ], [ "Davis", "Larry S.", "" ] ]
TITLE: The Role of Context Selection in Object Detection ABSTRACT: We investigate the reasons why context in object detection has limited utility by isolating and evaluating the predictive power of different context cues under ideal conditions in which context provided by an oracle. Based on this study, we propose a region-based context re-scoring method with dynamic context selection to remove noise and emphasize informative context. We introduce latent indicator variables to select (or ignore) potential contextual regions, and learn the selection strategy with latent-SVM. We conduct experiments to evaluate the performance of the proposed context selection method on the SUN RGB-D dataset. The method achieves a significant improvement in terms of mean average precision (mAP), compared with both appearance based detectors and a conventional context model without the selection scheme.
no_new_dataset
0.954393
1609.03020
Daniele Sgandurra
Daniele Sgandurra, Luis Mu\~noz-Gonz\'alez, Rabih Mohsen, Emil C. Lupu
Automated Dynamic Analysis of Ransomware: Benefits, Limitations and use for Detection
null
null
null
null
cs.CR
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Recent statistics show that in 2015 more than 140 millions new malware samples have been found. Among these, a large portion is due to ransomware, the class of malware whose specific goal is to render the victim's system unusable, in particular by encrypting important files, and then ask the user to pay a ransom to revert the damage. Several ransomware include sophisticated packing techniques, and are hence difficult to statically analyse. We present EldeRan, a machine learning approach for dynamically analysing and classifying ransomware. EldeRan monitors a set of actions performed by applications in their first phases of installation checking for characteristics signs of ransomware. Our tests over a dataset of 582 ransomware belonging to 11 families, and with 942 goodware applications, show that EldeRan achieves an area under the ROC curve of 0.995. Furthermore, EldeRan works without requiring that an entire ransomware family is available beforehand. These results suggest that dynamic analysis can support ransomware detection, since ransomware samples exhibit a set of characteristic features at run-time that are common across families, and that helps the early detection of new variants. We also outline some limitations of dynamic analysis for ransomware and propose possible solutions.
[ { "version": "v1", "created": "Sat, 10 Sep 2016 09:49:36 GMT" } ]
2016-09-13T00:00:00
[ [ "Sgandurra", "Daniele", "" ], [ "Muñoz-González", "Luis", "" ], [ "Mohsen", "Rabih", "" ], [ "Lupu", "Emil C.", "" ] ]
TITLE: Automated Dynamic Analysis of Ransomware: Benefits, Limitations and use for Detection ABSTRACT: Recent statistics show that in 2015 more than 140 millions new malware samples have been found. Among these, a large portion is due to ransomware, the class of malware whose specific goal is to render the victim's system unusable, in particular by encrypting important files, and then ask the user to pay a ransom to revert the damage. Several ransomware include sophisticated packing techniques, and are hence difficult to statically analyse. We present EldeRan, a machine learning approach for dynamically analysing and classifying ransomware. EldeRan monitors a set of actions performed by applications in their first phases of installation checking for characteristics signs of ransomware. Our tests over a dataset of 582 ransomware belonging to 11 families, and with 942 goodware applications, show that EldeRan achieves an area under the ROC curve of 0.995. Furthermore, EldeRan works without requiring that an entire ransomware family is available beforehand. These results suggest that dynamic analysis can support ransomware detection, since ransomware samples exhibit a set of characteristic features at run-time that are common across families, and that helps the early detection of new variants. We also outline some limitations of dynamic analysis for ransomware and propose possible solutions.
no_new_dataset
0.928539
1609.03146
Mathieu Guillame-Bert
Mathieu Guillame-Bert
Honey: A dataflow programming language for the processing, featurization and analysis of multivariate, asynchronous and non-uniformly sampled scalar symbolic time sequences
The source code of four presented tasks are available on the Honey website
null
null
null
cs.PL
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We introduce HONEY; a new specialized programming language designed to facilitate the processing of multivariate, asynchronous and non-uniformly sampled symbolic and scalar time sequences. When compiled, a Honey program is transformed into a static process flow diagram, which is then executed by a virtual machine. Honey's most notable features are: (1) Honey introduces a new, efficient and non-prone to error paradigm for defining recursive process flow diagrams from text input with the mindset of imperative programming. Honey's specialized, high level and concise syntax allows fast and easy writing, reading and maintenance of complex processing of large scalar symbolic time sequence datasets. (2) Honey guarantees programs will be executed similarly on static or real-time streaming datasets. (3) Honey's IDE includes an interactive visualization tool which allows for an interactive exploration of the intermediate and final outputs. This combination enables fast incremental prototyping, debugging, monitoring and maintenance of complex programs. (4) In case of large datasets (larger than the available memory), Honey programs can be executed to process input greedily. (5) The graphical structure of a compiled program provides several desirable properties, including distributed and/or paralleled execution, memory optimization, and program structure visualization. (6) Honey contains a large library of both common and novel operators developed through various research projects. An open source C++ implementation of Honey as well as the Honey IDE and the interactive data visualizer are publicly available.
[ { "version": "v1", "created": "Sun, 11 Sep 2016 10:18:29 GMT" } ]
2016-09-13T00:00:00
[ [ "Guillame-Bert", "Mathieu", "" ] ]
TITLE: Honey: A dataflow programming language for the processing, featurization and analysis of multivariate, asynchronous and non-uniformly sampled scalar symbolic time sequences ABSTRACT: We introduce HONEY; a new specialized programming language designed to facilitate the processing of multivariate, asynchronous and non-uniformly sampled symbolic and scalar time sequences. When compiled, a Honey program is transformed into a static process flow diagram, which is then executed by a virtual machine. Honey's most notable features are: (1) Honey introduces a new, efficient and non-prone to error paradigm for defining recursive process flow diagrams from text input with the mindset of imperative programming. Honey's specialized, high level and concise syntax allows fast and easy writing, reading and maintenance of complex processing of large scalar symbolic time sequence datasets. (2) Honey guarantees programs will be executed similarly on static or real-time streaming datasets. (3) Honey's IDE includes an interactive visualization tool which allows for an interactive exploration of the intermediate and final outputs. This combination enables fast incremental prototyping, debugging, monitoring and maintenance of complex programs. (4) In case of large datasets (larger than the available memory), Honey programs can be executed to process input greedily. (5) The graphical structure of a compiled program provides several desirable properties, including distributed and/or paralleled execution, memory optimization, and program structure visualization. (6) Honey contains a large library of both common and novel operators developed through various research projects. An open source C++ implementation of Honey as well as the Honey IDE and the interactive data visualizer are publicly available.
no_new_dataset
0.940898
1609.03205
Ella Rabinovich
Ella Rabinovich and Shuly Wintner
Unsupervised Identification of Translationese
TACL2015, 14 pages
null
null
null
cs.CL
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Translated texts are distinctively different from original ones, to the extent that supervised text classification methods can distinguish between them with high accuracy. These differences were proven useful for statistical machine translation. However, it has been suggested that the accuracy of translation detection deteriorates when the classifier is evaluated outside the domain it was trained on. We show that this is indeed the case, in a variety of evaluation scenarios. We then show that unsupervised classification is highly accurate on this task. We suggest a method for determining the correct labels of the clustering outcomes, and then use the labels for voting, improving the accuracy even further. Moreover, we suggest a simple method for clustering in the challenging case of mixed-domain datasets, in spite of the dominance of domain-related features over translation-related ones. The result is an effective, fully-unsupervised method for distinguishing between original and translated texts that can be applied to new domains with reasonable accuracy.
[ { "version": "v1", "created": "Sun, 11 Sep 2016 19:52:28 GMT" } ]
2016-09-13T00:00:00
[ [ "Rabinovich", "Ella", "" ], [ "Wintner", "Shuly", "" ] ]
TITLE: Unsupervised Identification of Translationese ABSTRACT: Translated texts are distinctively different from original ones, to the extent that supervised text classification methods can distinguish between them with high accuracy. These differences were proven useful for statistical machine translation. However, it has been suggested that the accuracy of translation detection deteriorates when the classifier is evaluated outside the domain it was trained on. We show that this is indeed the case, in a variety of evaluation scenarios. We then show that unsupervised classification is highly accurate on this task. We suggest a method for determining the correct labels of the clustering outcomes, and then use the labels for voting, improving the accuracy even further. Moreover, we suggest a simple method for clustering in the challenging case of mixed-domain datasets, in spite of the dominance of domain-related features over translation-related ones. The result is an effective, fully-unsupervised method for distinguishing between original and translated texts that can be applied to new domains with reasonable accuracy.
no_new_dataset
0.949342
1609.03224
Ali Fatih Demir
A. Fatih Demir, Huseyin Arslan, Ismail Uysal
Bio-Inspired Filter Banks for SSVEP-based Brain-Computer Interfaces
2016 IEEE International Conference on Biomedical and Health Informatics (BHI)
2016 IEEE-EMBS International Conference on Biomedical and Health Informatics (BHI), Feb. 2016, pp. 144-147
10.1109/BHI.2016.7455855
null
cs.HC q-bio.NC
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Brain-computer interfaces (BCI) have the potential to play a vital role in future healthcare technologies by providing an alternative way of communication and control. More specifically, steady-state visual evoked potential (SSVEP) based BCIs have the advantage of higher accuracy and higher information transfer rate (ITR). In order to fully exploit the capabilities of such devices, it is necessary to understand the features of SSVEP and design the system considering its biological characteristics. This paper introduces bio-inspired filter banks (BIFB) for a novel SSVEP frequency detection method. It is known that SSVEP response to a flickering visual stimulus is frequency selective and gets weaker as the frequency of the stimuli increases. In the proposed approach, the gain and bandwidth of the filters are designed and tuned based on these characteristics while also incorporating harmonic SSVEP responses. This method not only improves the accuracy but also increases the available number of commands by allowing the use of stimuli frequencies elicit weak SSVEP responses. The BIFB method achieved reliable performance when tested on datasets available online and compared with two well-known SSVEP frequency detection methods, power spectral density analysis (PSDA) and canonical correlation analysis (CCA). The results show the potential of bio-inspired design which will be extended to include further SSVEP characteristic (e.g. time-domain waveform) for future SSVEP based BCIs.
[ { "version": "v1", "created": "Sun, 11 Sep 2016 22:15:12 GMT" } ]
2016-09-13T00:00:00
[ [ "Demir", "A. Fatih", "" ], [ "Arslan", "Huseyin", "" ], [ "Uysal", "Ismail", "" ] ]
TITLE: Bio-Inspired Filter Banks for SSVEP-based Brain-Computer Interfaces ABSTRACT: Brain-computer interfaces (BCI) have the potential to play a vital role in future healthcare technologies by providing an alternative way of communication and control. More specifically, steady-state visual evoked potential (SSVEP) based BCIs have the advantage of higher accuracy and higher information transfer rate (ITR). In order to fully exploit the capabilities of such devices, it is necessary to understand the features of SSVEP and design the system considering its biological characteristics. This paper introduces bio-inspired filter banks (BIFB) for a novel SSVEP frequency detection method. It is known that SSVEP response to a flickering visual stimulus is frequency selective and gets weaker as the frequency of the stimuli increases. In the proposed approach, the gain and bandwidth of the filters are designed and tuned based on these characteristics while also incorporating harmonic SSVEP responses. This method not only improves the accuracy but also increases the available number of commands by allowing the use of stimuli frequencies elicit weak SSVEP responses. The BIFB method achieved reliable performance when tested on datasets available online and compared with two well-known SSVEP frequency detection methods, power spectral density analysis (PSDA) and canonical correlation analysis (CCA). The results show the potential of bio-inspired design which will be extended to include further SSVEP characteristic (e.g. time-domain waveform) for future SSVEP based BCIs.
no_new_dataset
0.949902
1609.03277
Mahamad Suhil
Sumithra R, Mahamad Suhil, D.S. Guru
Segmentation and Classification of Skin Lesions for Disease Diagnosis
10 pages, 6 figures, 2 Tables in Elsevier, Proceedia Computer Science, International Conference on Advanced Computing Technologies and Applications (ICACTA-2015)
null
10.1016/j.procs.2015.03.090
null
cs.CV
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
In this paper, a novel approach for automatic segmentation and classification of skin lesions is proposed. Initially, skin images are filtered to remove unwanted hairs and noise and then the segmentation process is carried out to extract lesion areas. For segmentation, a region growing method is applied by automatic initialization of seed points. The segmentation performance is measured with different well known measures and the results are appreciable. Subsequently, the extracted lesion areas are represented by color and texture features. SVM and k-NN classifiers are used along with their fusion for the classification using the extracted features. The performance of the system is tested on our own dataset of 726 samples from 141 images consisting of 5 different classes of diseases. The results are very promising with 46.71% and 34% of F-measure using SVM and k-NN classifier respectively and with 61% of F-measure for fusion of SVM and k-NN.
[ { "version": "v1", "created": "Mon, 12 Sep 2016 06:05:55 GMT" } ]
2016-09-13T00:00:00
[ [ "R", "Sumithra", "" ], [ "Suhil", "Mahamad", "" ], [ "Guru", "D. S.", "" ] ]
TITLE: Segmentation and Classification of Skin Lesions for Disease Diagnosis ABSTRACT: In this paper, a novel approach for automatic segmentation and classification of skin lesions is proposed. Initially, skin images are filtered to remove unwanted hairs and noise and then the segmentation process is carried out to extract lesion areas. For segmentation, a region growing method is applied by automatic initialization of seed points. The segmentation performance is measured with different well known measures and the results are appreciable. Subsequently, the extracted lesion areas are represented by color and texture features. SVM and k-NN classifiers are used along with their fusion for the classification using the extracted features. The performance of the system is tested on our own dataset of 726 samples from 141 images consisting of 5 different classes of diseases. The results are very promising with 46.71% and 34% of F-measure using SVM and k-NN classifier respectively and with 61% of F-measure for fusion of SVM and k-NN.
new_dataset
0.960805
1609.03536
Zhenheng Yang
Zhenheng Yang and Ram Nevatia
A Multi-Scale Cascade Fully Convolutional Network Face Detector
Accepted to ICPR 16'
null
null
null
cs.CV
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Face detection is challenging as faces in images could be present at arbitrary locations and in different scales. We propose a three-stage cascade structure based on fully convolutional neural networks (FCNs). It first proposes the approximate locations where the faces may be, then aims to find the accurate location by zooming on to the faces. Each level of the FCN cascade is a multi-scale fully-convolutional network, which generates scores at different locations and in different scales. A score map is generated after each FCN stage. Probable regions of face are selected and fed to the next stage. The number of proposals is decreased after each level, and the areas of regions are decreased to more precisely fit the face. Compared to passing proposals directly between stages, passing probable regions can decrease the number of proposals and reduce the cases where first stage doesn't propose good bounding boxes. We show that by using FCN and score map, the FCN cascade face detector can achieve strong performance on public datasets.
[ { "version": "v1", "created": "Mon, 12 Sep 2016 19:13:46 GMT" } ]
2016-09-13T00:00:00
[ [ "Yang", "Zhenheng", "" ], [ "Nevatia", "Ram", "" ] ]
TITLE: A Multi-Scale Cascade Fully Convolutional Network Face Detector ABSTRACT: Face detection is challenging as faces in images could be present at arbitrary locations and in different scales. We propose a three-stage cascade structure based on fully convolutional neural networks (FCNs). It first proposes the approximate locations where the faces may be, then aims to find the accurate location by zooming on to the faces. Each level of the FCN cascade is a multi-scale fully-convolutional network, which generates scores at different locations and in different scales. A score map is generated after each FCN stage. Probable regions of face are selected and fed to the next stage. The number of proposals is decreased after each level, and the areas of regions are decreased to more precisely fit the face. Compared to passing proposals directly between stages, passing probable regions can decrease the number of proposals and reduce the cases where first stage doesn't propose good bounding boxes. We show that by using FCN and score map, the FCN cascade face detector can achieve strong performance on public datasets.
no_new_dataset
0.957794
1609.03544
Xin Jiang
Xin Jiang, Rebecca Willett
Online Data Thinning via Multi-Subspace Tracking
32 pages, 10 figures
null
null
null
stat.ML cs.LG
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
In an era of ubiquitous large-scale streaming data, the availability of data far exceeds the capacity of expert human analysts. In many settings, such data is either discarded or stored unprocessed in datacenters. This paper proposes a method of online data thinning, in which large-scale streaming datasets are winnowed to preserve unique, anomalous, or salient elements for timely expert analysis. At the heart of this proposed approach is an online anomaly detection method based on dynamic, low-rank Gaussian mixture models. Specifically, the high-dimensional covariances matrices associated with the Gaussian components are associated with low-rank models. According to this model, most observations lie near a union of subspaces. The low-rank modeling mitigates the curse of dimensionality associated with anomaly detection for high-dimensional data, and recent advances in subspace clustering and subspace tracking allow the proposed method to adapt to dynamic environments. Furthermore, the proposed method allows subsampling, is robust to missing data, and uses a mini-batch online optimization approach. The resulting algorithms are scalable, efficient, and are capable of operating in real time. Experiments on wide-area motion imagery and e-mail databases illustrate the efficacy of the proposed approach.
[ { "version": "v1", "created": "Mon, 12 Sep 2016 19:34:02 GMT" } ]
2016-09-13T00:00:00
[ [ "Jiang", "Xin", "" ], [ "Willett", "Rebecca", "" ] ]
TITLE: Online Data Thinning via Multi-Subspace Tracking ABSTRACT: In an era of ubiquitous large-scale streaming data, the availability of data far exceeds the capacity of expert human analysts. In many settings, such data is either discarded or stored unprocessed in datacenters. This paper proposes a method of online data thinning, in which large-scale streaming datasets are winnowed to preserve unique, anomalous, or salient elements for timely expert analysis. At the heart of this proposed approach is an online anomaly detection method based on dynamic, low-rank Gaussian mixture models. Specifically, the high-dimensional covariances matrices associated with the Gaussian components are associated with low-rank models. According to this model, most observations lie near a union of subspaces. The low-rank modeling mitigates the curse of dimensionality associated with anomaly detection for high-dimensional data, and recent advances in subspace clustering and subspace tracking allow the proposed method to adapt to dynamic environments. Furthermore, the proposed method allows subsampling, is robust to missing data, and uses a mini-batch online optimization approach. The resulting algorithms are scalable, efficient, and are capable of operating in real time. Experiments on wide-area motion imagery and e-mail databases illustrate the efficacy of the proposed approach.
no_new_dataset
0.949856
1604.08504
Yao Lu
Linqing Liu, Yao Lu, Ye Luo, Renxian Zhang, Laurent Itti and Jianwei Lu
Detecting "Smart" Spammers On Social Network: A Topic Model Approach
NAACL-HLT 2016, Student Research Workshop
null
10.18653/v1/N16-2007
null
cs.CL cs.SI
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Spammer detection on social network is a challenging problem. The rigid anti-spam rules have resulted in emergence of "smart" spammers. They resemble legitimate users who are difficult to identify. In this paper, we present a novel spammer classification approach based on Latent Dirichlet Allocation(LDA), a topic model. Our approach extracts both the local and the global information of topic distribution patterns, which capture the essence of spamming. Tested on one benchmark dataset and one self-collected dataset, our proposed method outperforms other state-of-the-art methods in terms of averaged F1-score.
[ { "version": "v1", "created": "Thu, 28 Apr 2016 16:36:35 GMT" }, { "version": "v2", "created": "Thu, 9 Jun 2016 06:50:36 GMT" } ]
2016-09-12T00:00:00
[ [ "Liu", "Linqing", "" ], [ "Lu", "Yao", "" ], [ "Luo", "Ye", "" ], [ "Zhang", "Renxian", "" ], [ "Itti", "Laurent", "" ], [ "Lu", "Jianwei", "" ] ]
TITLE: Detecting "Smart" Spammers On Social Network: A Topic Model Approach ABSTRACT: Spammer detection on social network is a challenging problem. The rigid anti-spam rules have resulted in emergence of "smart" spammers. They resemble legitimate users who are difficult to identify. In this paper, we present a novel spammer classification approach based on Latent Dirichlet Allocation(LDA), a topic model. Our approach extracts both the local and the global information of topic distribution patterns, which capture the essence of spamming. Tested on one benchmark dataset and one self-collected dataset, our proposed method outperforms other state-of-the-art methods in terms of averaged F1-score.
new_dataset
0.957873
1609.02631
Varvara Kollia
Varvara Kollia, Oguz H. Elibol
Distributed Processing of Biosignal-Database for Emotion Recognition with Mahout
4 pages, 5 png figures
null
null
null
stat.ML cs.LG
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
This paper investigates the use of distributed processing on the problem of emotion recognition from physiological sensors using a popular machine learning library on distributed mode. Specifically, we run a random forests classifier on the biosignal-data, which have been pre-processed to form exclusive groups in an unsupervised fashion, on a Cloudera cluster using Mahout. The use of distributed processing significantly reduces the time required for the offline training of the classifier, enabling processing of large physiological datasets through many iterations.
[ { "version": "v1", "created": "Fri, 9 Sep 2016 01:13:20 GMT" } ]
2016-09-12T00:00:00
[ [ "Kollia", "Varvara", "" ], [ "Elibol", "Oguz H.", "" ] ]
TITLE: Distributed Processing of Biosignal-Database for Emotion Recognition with Mahout ABSTRACT: This paper investigates the use of distributed processing on the problem of emotion recognition from physiological sensors using a popular machine learning library on distributed mode. Specifically, we run a random forests classifier on the biosignal-data, which have been pre-processed to form exclusive groups in an unsupervised fashion, on a Cloudera cluster using Mahout. The use of distributed processing significantly reduces the time required for the offline training of the classifier, enabling processing of large physiological datasets through many iterations.
no_new_dataset
0.949902
1609.02715
Amin Fehri
Amin Fehri (CMM), Santiago Velasco-Forero (CMM), Fernand Meyer (CMM)
Automatic Selection of Stochastic Watershed Hierarchies
in European Conference of Signal Processing (EUSIPCO), 2016, Budapest, Hungary
null
null
null
cs.CV cs.LG
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The segmentation, seen as the association of a partition with an image, is a difficult task. It can be decomposed in two steps: at first, a family of contours associated with a series of nested partitions (or hierarchy) is created and organized, then pertinent contours are extracted. A coarser partition is obtained by merging adjacent regions of a finer partition. The strength of a contour is then measured by the level of the hierarchy for which its two adjacent regions merge. We present an automatic segmentation strategy using a wide range of stochastic watershed hierarchies. For a given set of homogeneous images, our approach selects automatically the best hierarchy and cut level to perform image simplification given an evaluation score. Experimental results illustrate the advantages of our approach on several real-life images datasets.
[ { "version": "v1", "created": "Fri, 9 Sep 2016 09:26:22 GMT" } ]
2016-09-12T00:00:00
[ [ "Fehri", "Amin", "", "CMM" ], [ "Velasco-Forero", "Santiago", "", "CMM" ], [ "Meyer", "Fernand", "", "CMM" ] ]
TITLE: Automatic Selection of Stochastic Watershed Hierarchies ABSTRACT: The segmentation, seen as the association of a partition with an image, is a difficult task. It can be decomposed in two steps: at first, a family of contours associated with a series of nested partitions (or hierarchy) is created and organized, then pertinent contours are extracted. A coarser partition is obtained by merging adjacent regions of a finer partition. The strength of a contour is then measured by the level of the hierarchy for which its two adjacent regions merge. We present an automatic segmentation strategy using a wide range of stochastic watershed hierarchies. For a given set of homogeneous images, our approach selects automatically the best hierarchy and cut level to perform image simplification given an evaluation score. Experimental results illustrate the advantages of our approach on several real-life images datasets.
no_new_dataset
0.954942
1609.02727
Vlad Sandulescu
Vlad Sandulescu, Martin Ester
Detecting Singleton Review Spammers Using Semantic Similarity
6 pages, WWW 2015
WWW '15 Companion Proceedings of the 24th International Conference on World Wide Web, 2015, p.971-976
10.1145/2740908.2742570
null
cs.CL cs.LG
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Online reviews have increasingly become a very important resource for consumers when making purchases. Though it is becoming more and more difficult for people to make well-informed buying decisions without being deceived by fake reviews. Prior works on the opinion spam problem mostly considered classifying fake reviews using behavioral user patterns. They focused on prolific users who write more than a couple of reviews, discarding one-time reviewers. The number of singleton reviewers however is expected to be high for many review websites. While behavioral patterns are effective when dealing with elite users, for one-time reviewers, the review text needs to be exploited. In this paper we tackle the problem of detecting fake reviews written by the same person using multiple names, posting each review under a different name. We propose two methods to detect similar reviews and show the results generally outperform the vectorial similarity measures used in prior works. The first method extends the semantic similarity between words to the reviews level. The second method is based on topic modeling and exploits the similarity of the reviews topic distributions using two models: bag-of-words and bag-of-opinion-phrases. The experiments were conducted on reviews from three different datasets: Yelp (57K reviews), Trustpilot (9K reviews) and Ott dataset (800 reviews).
[ { "version": "v1", "created": "Fri, 9 Sep 2016 09:58:45 GMT" } ]
2016-09-12T00:00:00
[ [ "Sandulescu", "Vlad", "" ], [ "Ester", "Martin", "" ] ]
TITLE: Detecting Singleton Review Spammers Using Semantic Similarity ABSTRACT: Online reviews have increasingly become a very important resource for consumers when making purchases. Though it is becoming more and more difficult for people to make well-informed buying decisions without being deceived by fake reviews. Prior works on the opinion spam problem mostly considered classifying fake reviews using behavioral user patterns. They focused on prolific users who write more than a couple of reviews, discarding one-time reviewers. The number of singleton reviewers however is expected to be high for many review websites. While behavioral patterns are effective when dealing with elite users, for one-time reviewers, the review text needs to be exploited. In this paper we tackle the problem of detecting fake reviews written by the same person using multiple names, posting each review under a different name. We propose two methods to detect similar reviews and show the results generally outperform the vectorial similarity measures used in prior works. The first method extends the semantic similarity between words to the reviews level. The second method is based on topic modeling and exploits the similarity of the reviews topic distributions using two models: bag-of-words and bag-of-opinion-phrases. The experiments were conducted on reviews from three different datasets: Yelp (57K reviews), Trustpilot (9K reviews) and Ott dataset (800 reviews).
no_new_dataset
0.949669
1609.02745
Sebastian Ruder
Sebastian Ruder, Parsa Ghaffari, and John G. Breslin
A Hierarchical Model of Reviews for Aspect-based Sentiment Analysis
To be published at EMNLP 2016, 7 pages
null
null
null
cs.CL cs.LG
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Opinion mining from customer reviews has become pervasive in recent years. Sentences in reviews, however, are usually classified independently, even though they form part of a review's argumentative structure. Intuitively, sentences in a review build and elaborate upon each other; knowledge of the review structure and sentential context should thus inform the classification of each sentence. We demonstrate this hypothesis for the task of aspect-based sentiment analysis by modeling the interdependencies of sentences in a review with a hierarchical bidirectional LSTM. We show that the hierarchical model outperforms two non-hierarchical baselines, obtains results competitive with the state-of-the-art, and outperforms the state-of-the-art on five multilingual, multi-domain datasets without any hand-engineered features or external resources.
[ { "version": "v1", "created": "Fri, 9 Sep 2016 11:16:15 GMT" } ]
2016-09-12T00:00:00
[ [ "Ruder", "Sebastian", "" ], [ "Ghaffari", "Parsa", "" ], [ "Breslin", "John G.", "" ] ]
TITLE: A Hierarchical Model of Reviews for Aspect-based Sentiment Analysis ABSTRACT: Opinion mining from customer reviews has become pervasive in recent years. Sentences in reviews, however, are usually classified independently, even though they form part of a review's argumentative structure. Intuitively, sentences in a review build and elaborate upon each other; knowledge of the review structure and sentential context should thus inform the classification of each sentence. We demonstrate this hypothesis for the task of aspect-based sentiment analysis by modeling the interdependencies of sentences in a review with a hierarchical bidirectional LSTM. We show that the hierarchical model outperforms two non-hierarchical baselines, obtains results competitive with the state-of-the-art, and outperforms the state-of-the-art on five multilingual, multi-domain datasets without any hand-engineered features or external resources.
no_new_dataset
0.945951
1609.02781
Gabriel De Barros Paranhos Da Costa
Gabriel B. Paranhos da Costa, Welinton A. Contato, Tiago S. Nazare, Jo\~ao E. S. Batista Neto, Moacir Ponti
An empirical study on the effects of different types of noise in image classification tasks
null
null
null
null
cs.CV
http://creativecommons.org/licenses/by/4.0/
Image classification is one of the main research problems in computer vision and machine learning. Since in most real-world image classification applications there is no control over how the images are captured, it is necessary to consider the possibility that these images might be affected by noise (e.g. sensor noise in a low-quality surveillance camera). In this paper we analyse the impact of three different types of noise on descriptors extracted by two widely used feature extraction methods (LBP and HOG) and how denoising the images can help to mitigate this problem. We carry out experiments on two different datasets and consider several types of noise, noise levels, and denoising methods. Our results show that noise can hinder classification performance considerably and make classes harder to separate. Although denoising methods were not able to reach the same performance of the noise-free scenario, they improved classification results for noisy data.
[ { "version": "v1", "created": "Fri, 9 Sep 2016 13:19:41 GMT" } ]
2016-09-12T00:00:00
[ [ "da Costa", "Gabriel B. Paranhos", "" ], [ "Contato", "Welinton A.", "" ], [ "Nazare", "Tiago S.", "" ], [ "Neto", "João E. S. Batista", "" ], [ "Ponti", "Moacir", "" ] ]
TITLE: An empirical study on the effects of different types of noise in image classification tasks ABSTRACT: Image classification is one of the main research problems in computer vision and machine learning. Since in most real-world image classification applications there is no control over how the images are captured, it is necessary to consider the possibility that these images might be affected by noise (e.g. sensor noise in a low-quality surveillance camera). In this paper we analyse the impact of three different types of noise on descriptors extracted by two widely used feature extraction methods (LBP and HOG) and how denoising the images can help to mitigate this problem. We carry out experiments on two different datasets and consider several types of noise, noise levels, and denoising methods. Our results show that noise can hinder classification performance considerably and make classes harder to separate. Although denoising methods were not able to reach the same performance of the noise-free scenario, they improved classification results for noisy data.
no_new_dataset
0.948346
1609.02805
Nicolas Jaccard
Nicolas Jaccard, Thomas W. Rogers, Edward J. Morton, Lewis D. Griffin
Automated detection of smuggled high-risk security threats using Deep Learning
Submission for Crime Detection and Prevention conference 2016
null
null
null
cs.CV
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The security infrastructure is ill-equipped to detect and deter the smuggling of non-explosive devices that enable terror attacks such as those recently perpetrated in western Europe. The detection of so-called "small metallic threats" (SMTs) in cargo containers currently relies on statistical risk analysis, intelligence reports, and visual inspection of X-ray images by security officers. The latter is very slow and unreliable due to the difficulty of the task: objects potentially spanning less than 50 pixels have to be detected in images containing more than 2 million pixels against very complex and cluttered backgrounds. In this contribution, we demonstrate for the first time the use of Convolutional Neural Networks (CNNs), a type of Deep Learning, to automate the detection of SMTs in fullsize X-ray images of cargo containers. Novel approaches for dataset augmentation allowed to train CNNs from-scratch despite the scarcity of data available. We report fewer than 6% false alarms when detecting 90% SMTs synthetically concealed in stream-of-commerce images, which corresponds to an improvement of over an order of magnitude over conventional approaches such as Bag-of-Words (BoWs). The proposed scheme offers potentially super-human performance for a fraction of the time it would take for a security officers to carry out visual inspection (processing time is approximately 3.5s per container image).
[ { "version": "v1", "created": "Fri, 9 Sep 2016 14:14:52 GMT" } ]
2016-09-12T00:00:00
[ [ "Jaccard", "Nicolas", "" ], [ "Rogers", "Thomas W.", "" ], [ "Morton", "Edward J.", "" ], [ "Griffin", "Lewis D.", "" ] ]
TITLE: Automated detection of smuggled high-risk security threats using Deep Learning ABSTRACT: The security infrastructure is ill-equipped to detect and deter the smuggling of non-explosive devices that enable terror attacks such as those recently perpetrated in western Europe. The detection of so-called "small metallic threats" (SMTs) in cargo containers currently relies on statistical risk analysis, intelligence reports, and visual inspection of X-ray images by security officers. The latter is very slow and unreliable due to the difficulty of the task: objects potentially spanning less than 50 pixels have to be detected in images containing more than 2 million pixels against very complex and cluttered backgrounds. In this contribution, we demonstrate for the first time the use of Convolutional Neural Networks (CNNs), a type of Deep Learning, to automate the detection of SMTs in fullsize X-ray images of cargo containers. Novel approaches for dataset augmentation allowed to train CNNs from-scratch despite the scarcity of data available. We report fewer than 6% false alarms when detecting 90% SMTs synthetically concealed in stream-of-commerce images, which corresponds to an improvement of over an order of magnitude over conventional approaches such as Bag-of-Words (BoWs). The proposed scheme offers potentially super-human performance for a fraction of the time it would take for a security officers to carry out visual inspection (processing time is approximately 3.5s per container image).
no_new_dataset
0.948346
1609.02809
Edward Dixon Mr
Alexei Bastidas, Edward Dixon, Chris Loo, John Ryan
Harassment detection: a benchmark on the #HackHarassment dataset
Accepted to the Collaborative European Research Conference 2016
null
null
null
cs.CL
http://creativecommons.org/licenses/by/4.0/
Online harassment has been a problem to a greater or lesser extent since the early days of the internet. Previous work has applied anti-spam techniques like machine-learning based text classification (Reynolds, 2011) to detecting harassing messages. However, existing public datasets are limited in size, with labels of varying quality. The #HackHarassment initiative (an alliance of 1 tech companies and NGOs devoted to fighting bullying on the internet) has begun to address this issue by creating a new dataset superior to its predecssors in terms of both size and quality. As we (#HackHarassment) complete further rounds of labelling, later iterations of this dataset will increase the available samples by at least an order of magnitude, enabling corresponding improvements in the quality of machine learning models for harassment detection. In this paper, we introduce the first models built on the #HackHarassment dataset v1.0 (a new open dataset, which we are delighted to share with any interested researcherss) as a benchmark for future research.
[ { "version": "v1", "created": "Fri, 9 Sep 2016 14:23:02 GMT" } ]
2016-09-12T00:00:00
[ [ "Bastidas", "Alexei", "" ], [ "Dixon", "Edward", "" ], [ "Loo", "Chris", "" ], [ "Ryan", "John", "" ] ]
TITLE: Harassment detection: a benchmark on the #HackHarassment dataset ABSTRACT: Online harassment has been a problem to a greater or lesser extent since the early days of the internet. Previous work has applied anti-spam techniques like machine-learning based text classification (Reynolds, 2011) to detecting harassing messages. However, existing public datasets are limited in size, with labels of varying quality. The #HackHarassment initiative (an alliance of 1 tech companies and NGOs devoted to fighting bullying on the internet) has begun to address this issue by creating a new dataset superior to its predecssors in terms of both size and quality. As we (#HackHarassment) complete further rounds of labelling, later iterations of this dataset will increase the available samples by at least an order of magnitude, enabling corresponding improvements in the quality of machine learning models for harassment detection. In this paper, we introduce the first models built on the #HackHarassment dataset v1.0 (a new open dataset, which we are delighted to share with any interested researcherss) as a benchmark for future research.
new_dataset
0.957991
1609.02825
Xi Peng
Xi Peng, Qiong Hu, Junzhou Huang, Dimitris N. Metaxas
Track Facial Points in Unconstrained Videos
British Machine Vision Conference (BMVC), 2016
null
null
null
cs.CV
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Tracking Facial Points in unconstrained videos is challenging due to the non-rigid deformation that changes over time. In this paper, we propose to exploit incremental learning for person-specific alignment in wild conditions. Our approach takes advantage of part-based representation and cascade regression for robust and efficient alignment on each frame. Unlike existing methods that usually rely on models trained offline, we incrementally update the representation subspace and the cascade of regressors in a unified framework to achieve personalized modeling on the fly. To alleviate the drifting issue, the fitting results are evaluated using a deep neural network, where well-aligned faces are picked out to incrementally update the representation and fitting models. Both image and video datasets are employed to valid the proposed method. The results demonstrate the superior performance of our approach compared with existing approaches in terms of fitting accuracy and efficiency.
[ { "version": "v1", "created": "Fri, 9 Sep 2016 15:02:08 GMT" } ]
2016-09-12T00:00:00
[ [ "Peng", "Xi", "" ], [ "Hu", "Qiong", "" ], [ "Huang", "Junzhou", "" ], [ "Metaxas", "Dimitris N.", "" ] ]
TITLE: Track Facial Points in Unconstrained Videos ABSTRACT: Tracking Facial Points in unconstrained videos is challenging due to the non-rigid deformation that changes over time. In this paper, we propose to exploit incremental learning for person-specific alignment in wild conditions. Our approach takes advantage of part-based representation and cascade regression for robust and efficient alignment on each frame. Unlike existing methods that usually rely on models trained offline, we incrementally update the representation subspace and the cascade of regressors in a unified framework to achieve personalized modeling on the fly. To alleviate the drifting issue, the fitting results are evaluated using a deep neural network, where well-aligned faces are picked out to incrementally update the representation and fitting models. Both image and video datasets are employed to valid the proposed method. The results demonstrate the superior performance of our approach compared with existing approaches in terms of fitting accuracy and efficiency.
no_new_dataset
0.953232
1609.02839
Richard Oentaryo
Jovian Lin, Richard Oentaryo, Ee-Peng Lim, Casey Vu, Adrian Vu, Agus Kwee
Where is the Goldmine? Finding Promising Business Locations through Facebook Data Analytics
null
Proceedings of the ACM Conference on Hypertext and Social Media, Halifax, Canada, 2016, pp. 93-102
10.1145/2914586.2914588
null
cs.SI cs.IR
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
If you were to open your own cafe, would you not want to effortlessly identify the most suitable location to set up your shop? Choosing an optimal physical location is a critical decision for numerous businesses, as many factors contribute to the final choice of the location. In this paper, we seek to address the issue by investigating the use of publicly available Facebook Pages data---which include user check-ins, types of business, and business locations---to evaluate a user-selected physical location with respect to a type of business. Using a dataset of 20,877 food businesses in Singapore, we conduct analysis of several key factors including business categories, locations, and neighboring businesses. From these factors, we extract a set of relevant features and develop a robust predictive model to estimate the popularity of a business location. Our experiments have shown that the popularity of neighboring business contributes the key features to perform accurate prediction. We finally illustrate the practical usage of our proposed approach via an interactive web application system.
[ { "version": "v1", "created": "Fri, 9 Sep 2016 15:48:50 GMT" } ]
2016-09-12T00:00:00
[ [ "Lin", "Jovian", "" ], [ "Oentaryo", "Richard", "" ], [ "Lim", "Ee-Peng", "" ], [ "Vu", "Casey", "" ], [ "Vu", "Adrian", "" ], [ "Kwee", "Agus", "" ] ]
TITLE: Where is the Goldmine? Finding Promising Business Locations through Facebook Data Analytics ABSTRACT: If you were to open your own cafe, would you not want to effortlessly identify the most suitable location to set up your shop? Choosing an optimal physical location is a critical decision for numerous businesses, as many factors contribute to the final choice of the location. In this paper, we seek to address the issue by investigating the use of publicly available Facebook Pages data---which include user check-ins, types of business, and business locations---to evaluate a user-selected physical location with respect to a type of business. Using a dataset of 20,877 food businesses in Singapore, we conduct analysis of several key factors including business categories, locations, and neighboring businesses. From these factors, we extract a set of relevant features and develop a robust predictive model to estimate the popularity of a business location. Our experiments have shown that the popularity of neighboring business contributes the key features to perform accurate prediction. We finally illustrate the practical usage of our proposed approach via an interactive web application system.
no_new_dataset
0.938688
1603.08152
Yair Movshovitz-Attias
Yair Movshovitz-Attias, Takeo Kanade, Yaser Sheikh
How useful is photo-realistic rendering for visual learning?
Published in GMDL 2016 In conjunction with ECCV 2016
null
null
null
cs.CV
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Data seems cheap to get, and in many ways it is, but the process of creating a high quality labeled dataset from a mass of data is time-consuming and expensive. With the advent of rich 3D repositories, photo-realistic rendering systems offer the opportunity to provide nearly limitless data. Yet, their primary value for visual learning may be the quality of the data they can provide rather than the quantity. Rendering engines offer the promise of perfect labels in addition to the data: what the precise camera pose is; what the precise lighting location, temperature, and distribution is; what the geometry of the object is. In this work we focus on semi-automating dataset creation through use of synthetic data and apply this method to an important task -- object viewpoint estimation. Using state-of-the-art rendering software we generate a large labeled dataset of cars rendered densely in viewpoint space. We investigate the effect of rendering parameters on estimation performance and show realism is important. We show that generalizing from synthetic data is not harder than the domain adaptation required between two real-image datasets and that combining synthetic images with a small amount of real data improves estimation accuracy.
[ { "version": "v1", "created": "Sat, 26 Mar 2016 22:56:53 GMT" }, { "version": "v2", "created": "Thu, 8 Sep 2016 03:43:58 GMT" } ]
2016-09-09T00:00:00
[ [ "Movshovitz-Attias", "Yair", "" ], [ "Kanade", "Takeo", "" ], [ "Sheikh", "Yaser", "" ] ]
TITLE: How useful is photo-realistic rendering for visual learning? ABSTRACT: Data seems cheap to get, and in many ways it is, but the process of creating a high quality labeled dataset from a mass of data is time-consuming and expensive. With the advent of rich 3D repositories, photo-realistic rendering systems offer the opportunity to provide nearly limitless data. Yet, their primary value for visual learning may be the quality of the data they can provide rather than the quantity. Rendering engines offer the promise of perfect labels in addition to the data: what the precise camera pose is; what the precise lighting location, temperature, and distribution is; what the geometry of the object is. In this work we focus on semi-automating dataset creation through use of synthetic data and apply this method to an important task -- object viewpoint estimation. Using state-of-the-art rendering software we generate a large labeled dataset of cars rendered densely in viewpoint space. We investigate the effect of rendering parameters on estimation performance and show realism is important. We show that generalizing from synthetic data is not harder than the domain adaptation required between two real-image datasets and that combining synthetic images with a small amount of real data improves estimation accuracy.
no_new_dataset
0.510435
1608.03075
Sungheon Park
Sungheon Park, Jihye Hwang, Nojun Kwak
3D Human Pose Estimation Using Convolutional Neural Networks with 2D Pose Information
ECCV 2016 workshop
null
null
null
cs.CV
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
While there has been a success in 2D human pose estimation with convolutional neural networks (CNNs), 3D human pose estimation has not been thoroughly studied. In this paper, we tackle the 3D human pose estimation task with end-to-end learning using CNNs. Relative 3D positions between one joint and the other joints are learned via CNNs. The proposed method improves the performance of CNN with two novel ideas. First, we added 2D pose information to estimate a 3D pose from an image by concatenating 2D pose estimation result with the features from an image. Second, we have found that more accurate 3D poses are obtained by combining information on relative positions with respect to multiple joints, instead of just one root joint. Experimental results show that the proposed method achieves comparable performance to the state-of-the-art methods on Human 3.6m dataset.
[ { "version": "v1", "created": "Wed, 10 Aug 2016 08:18:30 GMT" }, { "version": "v2", "created": "Thu, 8 Sep 2016 02:25:08 GMT" } ]
2016-09-09T00:00:00
[ [ "Park", "Sungheon", "" ], [ "Hwang", "Jihye", "" ], [ "Kwak", "Nojun", "" ] ]
TITLE: 3D Human Pose Estimation Using Convolutional Neural Networks with 2D Pose Information ABSTRACT: While there has been a success in 2D human pose estimation with convolutional neural networks (CNNs), 3D human pose estimation has not been thoroughly studied. In this paper, we tackle the 3D human pose estimation task with end-to-end learning using CNNs. Relative 3D positions between one joint and the other joints are learned via CNNs. The proposed method improves the performance of CNN with two novel ideas. First, we added 2D pose information to estimate a 3D pose from an image by concatenating 2D pose estimation result with the features from an image. Second, we have found that more accurate 3D poses are obtained by combining information on relative positions with respect to multiple joints, instead of just one root joint. Experimental results show that the proposed method achieves comparable performance to the state-of-the-art methods on Human 3.6m dataset.
no_new_dataset
0.947624
1608.07068
Kuo-Hao Zeng
Kuo-Hao Zeng and Tseng-Hung Chen and Juan Carlos Niebles and Min Sun
Title Generation for User Generated Videos
14 pages, 4 figures, ECCV2016
null
null
null
cs.CV cs.AI cs.MM
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
A great video title describes the most salient event compactly and captures the viewer's attention. In contrast, video captioning tends to generate sentences that describe the video as a whole. Although generating a video title automatically is a very useful task, it is much less addressed than video captioning. We address video title generation for the first time by proposing two methods that extend state-of-the-art video captioners to this new task. First, we make video captioners highlight sensitive by priming them with a highlight detector. Our framework allows for jointly training a model for title generation and video highlight localization. Second, we induce high sentence diversity in video captioners, so that the generated titles are also diverse and catchy. This means that a large number of sentences might be required to learn the sentence structure of titles. Hence, we propose a novel sentence augmentation method to train a captioner with additional sentence-only examples that come without corresponding videos. We collected a large-scale Video Titles in the Wild (VTW) dataset of 18100 automatically crawled user-generated videos and titles. On VTW, our methods consistently improve title prediction accuracy, and achieve the best performance in both automatic and human evaluation. Finally, our sentence augmentation method also outperforms the baselines on the M-VAD dataset.
[ { "version": "v1", "created": "Thu, 25 Aug 2016 09:49:23 GMT" }, { "version": "v2", "created": "Thu, 8 Sep 2016 17:36:13 GMT" } ]
2016-09-09T00:00:00
[ [ "Zeng", "Kuo-Hao", "" ], [ "Chen", "Tseng-Hung", "" ], [ "Niebles", "Juan Carlos", "" ], [ "Sun", "Min", "" ] ]
TITLE: Title Generation for User Generated Videos ABSTRACT: A great video title describes the most salient event compactly and captures the viewer's attention. In contrast, video captioning tends to generate sentences that describe the video as a whole. Although generating a video title automatically is a very useful task, it is much less addressed than video captioning. We address video title generation for the first time by proposing two methods that extend state-of-the-art video captioners to this new task. First, we make video captioners highlight sensitive by priming them with a highlight detector. Our framework allows for jointly training a model for title generation and video highlight localization. Second, we induce high sentence diversity in video captioners, so that the generated titles are also diverse and catchy. This means that a large number of sentences might be required to learn the sentence structure of titles. Hence, we propose a novel sentence augmentation method to train a captioner with additional sentence-only examples that come without corresponding videos. We collected a large-scale Video Titles in the Wild (VTW) dataset of 18100 automatically crawled user-generated videos and titles. On VTW, our methods consistently improve title prediction accuracy, and achieve the best performance in both automatic and human evaluation. Finally, our sentence augmentation method also outperforms the baselines on the M-VAD dataset.
new_dataset
0.915658
1609.02020
Zhenyu Liao
Zhenyu Liao, Romain Couillet
Random matrices meet machine learning: a large dimensional analysis of LS-SVM
wrong article submitted
null
null
null
stat.ML cs.LG
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
This article proposes a performance analysis of kernel least squares support vector machines (LS-SVMs) based on a random matrix approach, in the regime where both the dimension of data $p$ and their number $n$ grow large at the same rate. Under a two-class Gaussian mixture model for the input data, we prove that the LS-SVM decision function is asymptotically normal with means and covariances shown to depend explicitly on the derivatives of the kernel function. This provides improved understanding along with new insights into the internal workings of SVM-type methods for large datasets.
[ { "version": "v1", "created": "Wed, 7 Sep 2016 15:39:24 GMT" }, { "version": "v2", "created": "Thu, 8 Sep 2016 07:26:00 GMT" } ]
2016-09-09T00:00:00
[ [ "Liao", "Zhenyu", "" ], [ "Couillet", "Romain", "" ] ]
TITLE: Random matrices meet machine learning: a large dimensional analysis of LS-SVM ABSTRACT: This article proposes a performance analysis of kernel least squares support vector machines (LS-SVMs) based on a random matrix approach, in the regime where both the dimension of data $p$ and their number $n$ grow large at the same rate. Under a two-class Gaussian mixture model for the input data, we prove that the LS-SVM decision function is asymptotically normal with means and covariances shown to depend explicitly on the derivatives of the kernel function. This provides improved understanding along with new insights into the internal workings of SVM-type methods for large datasets.
no_new_dataset
0.950041
1609.02258
Haishan Ye
Haishan Ye, Qiaoming Ye, Zhihua Zhang
Tighter bound of Sketched Generalized Matrix Approximation
null
null
null
null
cs.NA
http://creativecommons.org/licenses/by/4.0/
Generalized matrix approximation plays a fundamental role in many machine learning problems, such as CUR decomposition, kernel approximation, and matrix low rank approximation. Especially with today's applications involved in larger and larger dataset, more and more efficient generalized matrix approximation algorithems become a crucially important research issue. In this paper, we find new sketching techniques to reduce the size of the original data matrix to develop new matrix approximation algorithms. Our results derive a much tighter bound for the approximation than previous works: we obtain a $(1+\epsilon)$ approximation ratio with small sketched dimensions which implies a more efficient generalized matrix approximation.
[ { "version": "v1", "created": "Thu, 8 Sep 2016 04:01:02 GMT" } ]
2016-09-09T00:00:00
[ [ "Ye", "Haishan", "" ], [ "Ye", "Qiaoming", "" ], [ "Zhang", "Zhihua", "" ] ]
TITLE: Tighter bound of Sketched Generalized Matrix Approximation ABSTRACT: Generalized matrix approximation plays a fundamental role in many machine learning problems, such as CUR decomposition, kernel approximation, and matrix low rank approximation. Especially with today's applications involved in larger and larger dataset, more and more efficient generalized matrix approximation algorithems become a crucially important research issue. In this paper, we find new sketching techniques to reduce the size of the original data matrix to develop new matrix approximation algorithms. Our results derive a much tighter bound for the approximation than previous works: we obtain a $(1+\epsilon)$ approximation ratio with small sketched dimensions which implies a more efficient generalized matrix approximation.
no_new_dataset
0.949623
1609.02281
Kanji Tanaka
Kanji Tanaka
Deformable Map Matching for Uncertain Loop-Less Maps
7 pages, 8 figures, Draft of a paper submitted to a conference
null
null
null
cs.RO
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
In the classical context of robotic mapping and localization, map matching is typically defined as the task of finding a rigid transformation (i.e., 3DOF rotation/translation on the 2D moving plane) that aligns the query and reference maps built by mobile robots. This definition is valid in loop-rich trajectories that enable a mapper robot to close many loops, for which precise maps can be assumed. The same cannot be said about the newly emerging autonomous navigation and driving systems, which typically operate in loop-less trajectories that have no large loop (e.g., straight paths). In this paper, we propose a solution that overcomes this limitation by merging the two maps. Our study is motivated by the observation that even when there is no large loop in either the query or reference map, many loops can often be obtained in the merged map. We add two new aspects to map matching: (1) image retrieval with discriminative deep convolutional neural network (DCNN) features, which efficiently generates a small number of good initial alignment hypotheses; and (2) map merge, which jointly deforms the two maps to minimize differences in shape between them. To realize practical computation time, we also present a preemption scheme that avoids excessive evaluation of useless map-matching hypotheses. To verify our approach experimentally, we created a novel collection of uncertain loop-less maps by utilizing the recently published North Campus Long-Term (NCLT) dataset and its ground-truth GPS data. The results obtained using these map collections confirm that our approach improves on previous map-matching approaches.
[ { "version": "v1", "created": "Thu, 8 Sep 2016 05:43:42 GMT" } ]
2016-09-09T00:00:00
[ [ "Tanaka", "Kanji", "" ] ]
TITLE: Deformable Map Matching for Uncertain Loop-Less Maps ABSTRACT: In the classical context of robotic mapping and localization, map matching is typically defined as the task of finding a rigid transformation (i.e., 3DOF rotation/translation on the 2D moving plane) that aligns the query and reference maps built by mobile robots. This definition is valid in loop-rich trajectories that enable a mapper robot to close many loops, for which precise maps can be assumed. The same cannot be said about the newly emerging autonomous navigation and driving systems, which typically operate in loop-less trajectories that have no large loop (e.g., straight paths). In this paper, we propose a solution that overcomes this limitation by merging the two maps. Our study is motivated by the observation that even when there is no large loop in either the query or reference map, many loops can often be obtained in the merged map. We add two new aspects to map matching: (1) image retrieval with discriminative deep convolutional neural network (DCNN) features, which efficiently generates a small number of good initial alignment hypotheses; and (2) map merge, which jointly deforms the two maps to minimize differences in shape between them. To realize practical computation time, we also present a preemption scheme that avoids excessive evaluation of useless map-matching hypotheses. To verify our approach experimentally, we created a novel collection of uncertain loop-less maps by utilizing the recently published North Campus Long-Term (NCLT) dataset and its ground-truth GPS data. The results obtained using these map collections confirm that our approach improves on previous map-matching approaches.
new_dataset
0.943504
1609.02284
Jiyang Gao
Jiyang Gao, Ram Nevatia
Learning Action Concept Trees and Semantic Alignment Networks from Image-Description Data
16 pages, 5 figures
null
null
null
cs.CV
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Action classification in still images has been a popular research topic in computer vision. Labelling large scale datasets for action classification requires tremendous manual work, which is hard to scale up. Besides, the action categories in such datasets are pre-defined and vocabularies are fixed. However humans may describe the same action with different phrases, which leads to the difficulty of vocabulary expansion for traditional fully-supervised methods. We observe that large amounts of images with sentence descriptions are readily available on the Internet. The sentence descriptions can be regarded as weak labels for the images, which contain rich information and could be used to learn flexible expressions of action categories. We propose a method to learn an Action Concept Tree (ACT) and an Action Semantic Alignment (ASA) model for classification from image-description data via a two-stage learning process. A new dataset for the task of learning actions from descriptions is built. Experimental results show that our method outperforms several baseline methods significantly.
[ { "version": "v1", "created": "Thu, 8 Sep 2016 05:53:31 GMT" } ]
2016-09-09T00:00:00
[ [ "Gao", "Jiyang", "" ], [ "Nevatia", "Ram", "" ] ]
TITLE: Learning Action Concept Trees and Semantic Alignment Networks from Image-Description Data ABSTRACT: Action classification in still images has been a popular research topic in computer vision. Labelling large scale datasets for action classification requires tremendous manual work, which is hard to scale up. Besides, the action categories in such datasets are pre-defined and vocabularies are fixed. However humans may describe the same action with different phrases, which leads to the difficulty of vocabulary expansion for traditional fully-supervised methods. We observe that large amounts of images with sentence descriptions are readily available on the Internet. The sentence descriptions can be regarded as weak labels for the images, which contain rich information and could be used to learn flexible expressions of action categories. We propose a method to learn an Action Concept Tree (ACT) and an Action Semantic Alignment (ASA) model for classification from image-description data via a two-stage learning process. A new dataset for the task of learning actions from descriptions is built. Experimental results show that our method outperforms several baseline methods significantly.
new_dataset
0.959345
1609.02452
Andreas Bulling
Sabrina Hoppe, Andreas Bulling
End-to-End Eye Movement Detection Using Convolutional Neural Networks
null
null
null
null
cs.CV
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Common computational methods for automated eye movement detection - i.e. the task of detecting different types of eye movement in a continuous stream of gaze data - are limited in that they either involve thresholding on hand-crafted signal features, require individual detectors each only detecting a single movement, or require pre-segmented data. We propose a novel approach for eye movement detection that only involves learning a single detector end-to-end, i.e. directly from the continuous gaze data stream and simultaneously for different eye movements without any manual feature crafting or segmentation. Our method is based on convolutional neural networks (CNN) that recently demonstrated superior performance in a variety of tasks in computer vision, signal processing, and machine learning. We further introduce a novel multi-participant dataset that contains scripted and free-viewing sequences of ground-truth annotated saccades, fixations, and smooth pursuits. We show that our CNN-based method outperforms state-of-the-art baselines by a large margin on this challenging dataset, thereby underlining the significant potential of this approach for holistic, robust, and accurate eye movement protocol analysis.
[ { "version": "v1", "created": "Thu, 8 Sep 2016 14:58:15 GMT" } ]
2016-09-09T00:00:00
[ [ "Hoppe", "Sabrina", "" ], [ "Bulling", "Andreas", "" ] ]
TITLE: End-to-End Eye Movement Detection Using Convolutional Neural Networks ABSTRACT: Common computational methods for automated eye movement detection - i.e. the task of detecting different types of eye movement in a continuous stream of gaze data - are limited in that they either involve thresholding on hand-crafted signal features, require individual detectors each only detecting a single movement, or require pre-segmented data. We propose a novel approach for eye movement detection that only involves learning a single detector end-to-end, i.e. directly from the continuous gaze data stream and simultaneously for different eye movements without any manual feature crafting or segmentation. Our method is based on convolutional neural networks (CNN) that recently demonstrated superior performance in a variety of tasks in computer vision, signal processing, and machine learning. We further introduce a novel multi-participant dataset that contains scripted and free-viewing sequences of ground-truth annotated saccades, fixations, and smooth pursuits. We show that our CNN-based method outperforms state-of-the-art baselines by a large margin on this challenging dataset, thereby underlining the significant potential of this approach for holistic, robust, and accurate eye movement protocol analysis.
new_dataset
0.960175
1609.02469
Joseph Antony A
Joseph Antony, Kevin McGuinness, Noel E O Connor, Kieran Moran
Quantifying Radiographic Knee Osteoarthritis Severity using Deep Convolutional Neural Networks
Included in ICPR 2016 proceedings
null
null
null
cs.CV
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
This paper proposes a new approach to automatically quantify the severity of knee osteoarthritis (OA) from radiographs using deep convolutional neural networks (CNN). Clinically, knee OA severity is assessed using Kellgren \& Lawrence (KL) grades, a five point scale. Previous work on automatically predicting KL grades from radiograph images were based on training shallow classifiers using a variety of hand engineered features. We demonstrate that classification accuracy can be significantly improved using deep convolutional neural network models pre-trained on ImageNet and fine-tuned on knee OA images. Furthermore, we argue that it is more appropriate to assess the accuracy of automatic knee OA severity predictions using a continuous distance-based evaluation metric like mean squared error than it is to use classification accuracy. This leads to the formulation of the prediction of KL grades as a regression problem and further improves accuracy. Results on a dataset of X-ray images and KL grades from the Osteoarthritis Initiative (OAI) show a sizable improvement over the current state-of-the-art.
[ { "version": "v1", "created": "Thu, 8 Sep 2016 15:39:48 GMT" } ]
2016-09-09T00:00:00
[ [ "Antony", "Joseph", "" ], [ "McGuinness", "Kevin", "" ], [ "Connor", "Noel E O", "" ], [ "Moran", "Kieran", "" ] ]
TITLE: Quantifying Radiographic Knee Osteoarthritis Severity using Deep Convolutional Neural Networks ABSTRACT: This paper proposes a new approach to automatically quantify the severity of knee osteoarthritis (OA) from radiographs using deep convolutional neural networks (CNN). Clinically, knee OA severity is assessed using Kellgren \& Lawrence (KL) grades, a five point scale. Previous work on automatically predicting KL grades from radiograph images were based on training shallow classifiers using a variety of hand engineered features. We demonstrate that classification accuracy can be significantly improved using deep convolutional neural network models pre-trained on ImageNet and fine-tuned on knee OA images. Furthermore, we argue that it is more appropriate to assess the accuracy of automatic knee OA severity predictions using a continuous distance-based evaluation metric like mean squared error than it is to use classification accuracy. This leads to the formulation of the prediction of KL grades as a regression problem and further improves accuracy. Results on a dataset of X-ray images and KL grades from the Osteoarthritis Initiative (OAI) show a sizable improvement over the current state-of-the-art.
no_new_dataset
0.954563
1609.02521
Rohit Babbar
Rohit Babbar and Bernhard Shoelkopf
DiSMEC - Distributed Sparse Machines for Extreme Multi-label Classification
null
null
null
null
stat.ML cs.LG
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Extreme multi-label classification refers to supervised multi-label learning involving hundreds of thousands or even millions of labels. Datasets in extreme classification exhibit fit to power-law distribution, i.e. a large fraction of labels have very few positive instances in the data distribution. Most state-of-the-art approaches for extreme multi-label classification attempt to capture correlation among labels by embedding the label matrix to a low-dimensional linear sub-space. However, in the presence of power-law distributed extremely large and diverse label spaces, structural assumptions such as low rank can be easily violated. In this work, we present DiSMEC, which is a large-scale distributed framework for learning one-versus-rest linear classifiers coupled with explicit capacity control to control model size. Unlike most state-of-the-art methods, DiSMEC does not make any low rank assumptions on the label matrix. Using double layer of parallelization, DiSMEC can learn classifiers for datasets consisting hundreds of thousands labels within few hours. The explicit capacity control mechanism filters out spurious parameters which keep the model compact in size, without losing prediction accuracy. We conduct extensive empirical evaluation on publicly available real-world datasets consisting upto 670,000 labels. We compare DiSMEC with recent state-of-the-art approaches, including - SLEEC which is a leading approach for learning sparse local embeddings, and FastXML which is a tree-based approach optimizing ranking based loss function. On some of the datasets, DiSMEC can significantly boost prediction accuracies - 10% better compared to SLECC and 15% better compared to FastXML, in absolute terms.
[ { "version": "v1", "created": "Thu, 8 Sep 2016 18:17:25 GMT" } ]
2016-09-09T00:00:00
[ [ "Babbar", "Rohit", "" ], [ "Shoelkopf", "Bernhard", "" ] ]
TITLE: DiSMEC - Distributed Sparse Machines for Extreme Multi-label Classification ABSTRACT: Extreme multi-label classification refers to supervised multi-label learning involving hundreds of thousands or even millions of labels. Datasets in extreme classification exhibit fit to power-law distribution, i.e. a large fraction of labels have very few positive instances in the data distribution. Most state-of-the-art approaches for extreme multi-label classification attempt to capture correlation among labels by embedding the label matrix to a low-dimensional linear sub-space. However, in the presence of power-law distributed extremely large and diverse label spaces, structural assumptions such as low rank can be easily violated. In this work, we present DiSMEC, which is a large-scale distributed framework for learning one-versus-rest linear classifiers coupled with explicit capacity control to control model size. Unlike most state-of-the-art methods, DiSMEC does not make any low rank assumptions on the label matrix. Using double layer of parallelization, DiSMEC can learn classifiers for datasets consisting hundreds of thousands labels within few hours. The explicit capacity control mechanism filters out spurious parameters which keep the model compact in size, without losing prediction accuracy. We conduct extensive empirical evaluation on publicly available real-world datasets consisting upto 670,000 labels. We compare DiSMEC with recent state-of-the-art approaches, including - SLEEC which is a leading approach for learning sparse local embeddings, and FastXML which is a tree-based approach optimizing ranking based loss function. On some of the datasets, DiSMEC can significantly boost prediction accuracies - 10% better compared to SLECC and 15% better compared to FastXML, in absolute terms.
no_new_dataset
0.947527
1609.02531
Yu Sun
Matteo Bianchi, Jeannette Bohg, and Yu Sun
Latest Datasets and Technologies Presented in the Workshop on Grasping and Manipulation Datasets
null
null
null
null
cs.RO cs.AI
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
This paper reports the activities and outcomes in the Workshop on Grasping and Manipulation Datasets that was organized under the International Conference on Robotics and Automation (ICRA) 2016. The half day workshop was packed with nine invited talks, 12 interactive presentations, and one panel discussion with ten panelists. This paper summarizes all the talks and presentations and recaps what has been discussed in the panels session. This summary servers as a review of recent developments in data collection in grasping and manipulation. Many of the presentations describe ongoing efforts or explorations that could be achieved and fully available in a year or two. The panel discussion not only commented on the current approaches, but also indicates new directions and focuses. The workshop clearly displayed the importance of quality datasets in robotics and robotic grasping and manipulation field. Hopefully the workshop could motivate larger efforts to create big datasets that are comparable with big datasets in other communities such as computer vision.
[ { "version": "v1", "created": "Thu, 8 Sep 2016 19:01:59 GMT" } ]
2016-09-09T00:00:00
[ [ "Bianchi", "Matteo", "" ], [ "Bohg", "Jeannette", "" ], [ "Sun", "Yu", "" ] ]
TITLE: Latest Datasets and Technologies Presented in the Workshop on Grasping and Manipulation Datasets ABSTRACT: This paper reports the activities and outcomes in the Workshop on Grasping and Manipulation Datasets that was organized under the International Conference on Robotics and Automation (ICRA) 2016. The half day workshop was packed with nine invited talks, 12 interactive presentations, and one panel discussion with ten panelists. This paper summarizes all the talks and presentations and recaps what has been discussed in the panels session. This summary servers as a review of recent developments in data collection in grasping and manipulation. Many of the presentations describe ongoing efforts or explorations that could be achieved and fully available in a year or two. The panel discussion not only commented on the current approaches, but also indicates new directions and focuses. The workshop clearly displayed the importance of quality datasets in robotics and robotic grasping and manipulation field. Hopefully the workshop could motivate larger efforts to create big datasets that are comparable with big datasets in other communities such as computer vision.
no_new_dataset
0.950732
0807.4729
Adrian Melott
Adrian L. Melott (University of Kansas)
Long-term cycles in the history of life: Periodic biodiversity in the Paleobiology Database
Published in PLoS ONE. 5 pages, 3 figures. Version with live links, discussion available at http://www.plosone.org/article/info:doi/10.1371/journal.pone.0004044#top
PLoS ONE 3(12): e4044. (2008)
10.1371/journal.pone.0004044
null
q-bio.PE astro-ph physics.bio-ph physics.data-an physics.geo-ph q-bio.QM stat.AP
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Time series analysis of fossil biodiversity of marine invertebrates in the Paleobiology Database (PBDB) shows a significant periodicity at approximately 63 My, in agreement with previous analyses based on the Sepkoski database. I discuss how this result did not appear in a previous analysis of the PBDB. The existence of the 63 My periodicity, despite very different treatment of systematic error in both PBDB and Sepkoski databases strongly argues for consideration of its reality in the fossil record. Cross-spectral analysis of the two datasets finds that a 62 My periodicity coincides in phase by 1.6 My, equivalent to better than the errors in either measurement. Consequently, the two data sets not only contain the same strong periodicity, but its peaks and valleys closely correspond in time. Two other spectral peaks appear in the PBDB analysis, but appear to be artifacts associated with detrending and with the increased interval length. Sampling-standardization procedures implemented by the PBDB collaboration suggest that the signal is not an artifact of sampling bias. Further work should focus on finding the cause of the 62 My periodicity.
[ { "version": "v1", "created": "Tue, 29 Jul 2008 20:01:51 GMT" }, { "version": "v2", "created": "Fri, 1 Aug 2008 14:23:30 GMT" }, { "version": "v3", "created": "Fri, 26 Sep 2008 19:56:34 GMT" }, { "version": "v4", "created": "Tue, 25 Nov 2008 13:36:31 GMT" }, { "version": "v5", "created": "Sat, 13 Dec 2008 23:51:16 GMT" }, { "version": "v6", "created": "Wed, 24 Dec 2008 14:59:10 GMT" } ]
2016-09-08T00:00:00
[ [ "Melott", "Adrian L.", "", "University of Kansas" ] ]
TITLE: Long-term cycles in the history of life: Periodic biodiversity in the Paleobiology Database ABSTRACT: Time series analysis of fossil biodiversity of marine invertebrates in the Paleobiology Database (PBDB) shows a significant periodicity at approximately 63 My, in agreement with previous analyses based on the Sepkoski database. I discuss how this result did not appear in a previous analysis of the PBDB. The existence of the 63 My periodicity, despite very different treatment of systematic error in both PBDB and Sepkoski databases strongly argues for consideration of its reality in the fossil record. Cross-spectral analysis of the two datasets finds that a 62 My periodicity coincides in phase by 1.6 My, equivalent to better than the errors in either measurement. Consequently, the two data sets not only contain the same strong periodicity, but its peaks and valleys closely correspond in time. Two other spectral peaks appear in the PBDB analysis, but appear to be artifacts associated with detrending and with the increased interval length. Sampling-standardization procedures implemented by the PBDB collaboration suggest that the signal is not an artifact of sampling bias. Further work should focus on finding the cause of the 62 My periodicity.
no_new_dataset
0.938124
0911.1765
Ion Mandoiu
Justin Kennedy, Ion I. Mandoiu, and Bogdan Pasaniuc
GEDI: Scalable Algorithms for Genotype Error Detection and Imputation
null
null
null
null
cs.DS
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Genome-wide association studies generate very large datasets that require scalable analysis algorithms. In this report we describe the GEDI software package, which implements efficient algorithms for performing several common tasks in the analysis of population genotype data, including genotype error detection and correction, imputation of both randomly missing and untyped genotypes, and genotype phasing. Experimental results show that GEDI achieves high accuracy with a runtime scaling linearly with the number of markers and samples. The open source C++ code of GEDI, released under the GNU General Public License, is available for download at http://dna.engr.uconn.edu/software/GEDI/
[ { "version": "v1", "created": "Mon, 9 Nov 2009 23:35:41 GMT" } ]
2016-09-08T00:00:00
[ [ "Kennedy", "Justin", "" ], [ "Mandoiu", "Ion I.", "" ], [ "Pasaniuc", "Bogdan", "" ] ]
TITLE: GEDI: Scalable Algorithms for Genotype Error Detection and Imputation ABSTRACT: Genome-wide association studies generate very large datasets that require scalable analysis algorithms. In this report we describe the GEDI software package, which implements efficient algorithms for performing several common tasks in the analysis of population genotype data, including genotype error detection and correction, imputation of both randomly missing and untyped genotypes, and genotype phasing. Experimental results show that GEDI achieves high accuracy with a runtime scaling linearly with the number of markers and samples. The open source C++ code of GEDI, released under the GNU General Public License, is available for download at http://dna.engr.uconn.edu/software/GEDI/
no_new_dataset
0.949529
1602.03291
Habibur Rahman
Habibur Rahman and Lucas Joppa and Senjuti Basu Roy
Feature Based Task Recommendation in Crowdsourcing with Implicit Observations
null
null
null
null
cs.AI cs.HC
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Existing research in crowdsourcing has investigated how to recommend tasks to workers based on which task the workers have already completed, referred to as {\em implicit feedback}. We, on the other hand, investigate the task recommendation problem, where we leverage both implicit feedback and explicit features of the task. We assume that we are given a set of workers, a set of tasks, interactions (such as the number of times a worker has completed a particular task), and the presence of explicit features of each task (such as, task location). We intend to recommend tasks to the workers by exploiting the implicit interactions, and the presence or absence of explicit features in the tasks. We formalize the problem as an optimization problem, propose two alternative problem formulations and respective solutions that exploit implicit feedback, explicit features, as well as similarity between the tasks. We compare the efficacy of our proposed solutions against multiple state-of-the-art techniques using two large scale real world datasets.
[ { "version": "v1", "created": "Wed, 10 Feb 2016 08:06:32 GMT" }, { "version": "v2", "created": "Wed, 7 Sep 2016 05:13:51 GMT" } ]
2016-09-08T00:00:00
[ [ "Rahman", "Habibur", "" ], [ "Joppa", "Lucas", "" ], [ "Roy", "Senjuti Basu", "" ] ]
TITLE: Feature Based Task Recommendation in Crowdsourcing with Implicit Observations ABSTRACT: Existing research in crowdsourcing has investigated how to recommend tasks to workers based on which task the workers have already completed, referred to as {\em implicit feedback}. We, on the other hand, investigate the task recommendation problem, where we leverage both implicit feedback and explicit features of the task. We assume that we are given a set of workers, a set of tasks, interactions (such as the number of times a worker has completed a particular task), and the presence of explicit features of each task (such as, task location). We intend to recommend tasks to the workers by exploiting the implicit interactions, and the presence or absence of explicit features in the tasks. We formalize the problem as an optimization problem, propose two alternative problem formulations and respective solutions that exploit implicit feedback, explicit features, as well as similarity between the tasks. We compare the efficacy of our proposed solutions against multiple state-of-the-art techniques using two large scale real world datasets.
no_new_dataset
0.947186
1609.00496
Shu Liu
Shu Liu, Bo Li, Yangyu Fan, Zhe Guo, Ashok Samal
Label distribution based facial attractiveness computation by deep residual learning
3 pages, 3 figures. The first two authors are parallel first author
null
null
null
cs.CV
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Two challenges lie in the facial attractiveness computation research: the lack of true attractiveness labels (scores), and the lack of an accurate face representation. In order to address the first challenge, this paper recasts facial attractiveness computation as a label distribution learning (LDL) problem rather than a traditional single-label supervised learning task. In this way, the negative influence of the label incomplete problem can be reduced. Inspired by the recent promising work in face recognition using deep neural networks to learn effective features, the second challenge is expected to be solved from a deep learning point of view. A very deep residual network is utilized to enable automatic learning of hierarchical aesthetics representation. Integrating these two ideas, an end-to-end deep learning framework is established. Our approach achieves the best results on a standard benchmark SCUT-FBP dataset compared with other state-of-the-art work.
[ { "version": "v1", "created": "Fri, 2 Sep 2016 08:08:39 GMT" }, { "version": "v2", "created": "Wed, 7 Sep 2016 09:06:31 GMT" } ]
2016-09-08T00:00:00
[ [ "Liu", "Shu", "" ], [ "Li", "Bo", "" ], [ "Fan", "Yangyu", "" ], [ "Guo", "Zhe", "" ], [ "Samal", "Ashok", "" ] ]
TITLE: Label distribution based facial attractiveness computation by deep residual learning ABSTRACT: Two challenges lie in the facial attractiveness computation research: the lack of true attractiveness labels (scores), and the lack of an accurate face representation. In order to address the first challenge, this paper recasts facial attractiveness computation as a label distribution learning (LDL) problem rather than a traditional single-label supervised learning task. In this way, the negative influence of the label incomplete problem can be reduced. Inspired by the recent promising work in face recognition using deep neural networks to learn effective features, the second challenge is expected to be solved from a deep learning point of view. A very deep residual network is utilized to enable automatic learning of hierarchical aesthetics representation. Integrating these two ideas, an end-to-end deep learning framework is established. Our approach achieves the best results on a standard benchmark SCUT-FBP dataset compared with other state-of-the-art work.
no_new_dataset
0.949482
1609.01962
Arkaitz Zubiaga
Michal Lukasik, Kalina Bontcheva, Trevor Cohn, Arkaitz Zubiaga, Maria Liakata, Rob Procter
Using Gaussian Processes for Rumour Stance Classification in Social Media
null
null
null
null
cs.CL cs.IR cs.SI
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Social media tend to be rife with rumours while new reports are released piecemeal during breaking news. Interestingly, one can mine multiple reactions expressed by social media users in those situations, exploring their stance towards rumours, ultimately enabling the flagging of highly disputed rumours as being potentially false. In this work, we set out to develop an automated, supervised classifier that uses multi-task learning to classify the stance expressed in each individual tweet in a rumourous conversation as either supporting, denying or questioning the rumour. Using a classifier based on Gaussian Processes, and exploring its effectiveness on two datasets with very different characteristics and varying distributions of stances, we show that our approach consistently outperforms competitive baseline classifiers. Our classifier is especially effective in estimating the distribution of different types of stance associated with a given rumour, which we set forth as a desired characteristic for a rumour-tracking system that will warn both ordinary users of Twitter and professional news practitioners when a rumour is being rebutted.
[ { "version": "v1", "created": "Wed, 7 Sep 2016 12:33:02 GMT" } ]
2016-09-08T00:00:00
[ [ "Lukasik", "Michal", "" ], [ "Bontcheva", "Kalina", "" ], [ "Cohn", "Trevor", "" ], [ "Zubiaga", "Arkaitz", "" ], [ "Liakata", "Maria", "" ], [ "Procter", "Rob", "" ] ]
TITLE: Using Gaussian Processes for Rumour Stance Classification in Social Media ABSTRACT: Social media tend to be rife with rumours while new reports are released piecemeal during breaking news. Interestingly, one can mine multiple reactions expressed by social media users in those situations, exploring their stance towards rumours, ultimately enabling the flagging of highly disputed rumours as being potentially false. In this work, we set out to develop an automated, supervised classifier that uses multi-task learning to classify the stance expressed in each individual tweet in a rumourous conversation as either supporting, denying or questioning the rumour. Using a classifier based on Gaussian Processes, and exploring its effectiveness on two datasets with very different characteristics and varying distributions of stances, we show that our approach consistently outperforms competitive baseline classifiers. Our classifier is especially effective in estimating the distribution of different types of stance associated with a given rumour, which we set forth as a desired characteristic for a rumour-tracking system that will warn both ordinary users of Twitter and professional news practitioners when a rumour is being rebutted.
no_new_dataset
0.948965
1609.01984
Jinyoung Choi
Jinyoung Choi, Beom-Jin Lee, and Byoung-Tak Zhang
Human Body Orientation Estimation using Convolutional Neural Network
null
null
null
null
cs.RO cs.CV cs.LG
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Personal robots are expected to interact with the user by recognizing the user's face. However, in most of the service robot applications, the user needs to move himself/herself to allow the robot to see him/her face to face. To overcome such limitations, a method for estimating human body orientation is required. Previous studies used various components such as feature extractors and classification models to classify the orientation which resulted in low performance. For a more robust and accurate approach, we propose the light weight convolutional neural networks, an end to end system, for estimating human body orientation. Our body orientation estimation model achieved 81.58% and 94% accuracy with the benchmark dataset and our own dataset respectively. The proposed method can be used in a wide range of service robot applications which depend on the ability to estimate human body orientation. To show its usefulness in service robot applications, we designed a simple robot application which allows the robot to move towards the user's frontal plane. With this, we demonstrated an improved face detection rate.
[ { "version": "v1", "created": "Wed, 7 Sep 2016 13:53:26 GMT" } ]
2016-09-08T00:00:00
[ [ "Choi", "Jinyoung", "" ], [ "Lee", "Beom-Jin", "" ], [ "Zhang", "Byoung-Tak", "" ] ]
TITLE: Human Body Orientation Estimation using Convolutional Neural Network ABSTRACT: Personal robots are expected to interact with the user by recognizing the user's face. However, in most of the service robot applications, the user needs to move himself/herself to allow the robot to see him/her face to face. To overcome such limitations, a method for estimating human body orientation is required. Previous studies used various components such as feature extractors and classification models to classify the orientation which resulted in low performance. For a more robust and accurate approach, we propose the light weight convolutional neural networks, an end to end system, for estimating human body orientation. Our body orientation estimation model achieved 81.58% and 94% accuracy with the benchmark dataset and our own dataset respectively. The proposed method can be used in a wide range of service robot applications which depend on the ability to estimate human body orientation. To show its usefulness in service robot applications, we designed a simple robot application which allows the robot to move towards the user's frontal plane. With this, we demonstrated an improved face detection rate.
new_dataset
0.525673
1609.02053
Davide Zambrano
Davide Zambrano and Sander M. Bohte
Fast and Efficient Asynchronous Neural Computation with Adapting Spiking Neural Networks
14 pages, 9 figures
null
null
null
cs.NE
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Biological neurons communicate with a sparing exchange of pulses - spikes. It is an open question how real spiking neurons produce the kind of powerful neural computation that is possible with deep artificial neural networks, using only so very few spikes to communicate. Building on recent insights in neuroscience, we present an Adapting Spiking Neural Network (ASNN) based on adaptive spiking neurons. These spiking neurons efficiently encode information in spike-trains using a form of Asynchronous Pulsed Sigma-Delta coding while homeostatically optimizing their firing rate. In the proposed paradigm of spiking neuron computation, neural adaptation is tightly coupled to synaptic plasticity, to ensure that downstream neurons can correctly decode upstream spiking neurons. We show that this type of network is inherently able to carry out asynchronous and event-driven neural computation, while performing identical to corresponding artificial neural networks (ANNs). In particular, we show that these adaptive spiking neurons can be drop in replacements for ReLU neurons in standard feedforward ANNs comprised of such units. We demonstrate that this can also be successfully applied to a ReLU based deep convolutional neural network for classifying the MNIST dataset. The ASNN thus outperforms current Spiking Neural Networks (SNNs) implementations, while responding (up to) an order of magnitude faster and using an order of magnitude fewer spikes. Additionally, in a streaming setting where frames are continuously classified, we show that the ASNN requires substantially fewer network updates as compared to the corresponding ANN.
[ { "version": "v1", "created": "Wed, 7 Sep 2016 16:30:01 GMT" } ]
2016-09-08T00:00:00
[ [ "Zambrano", "Davide", "" ], [ "Bohte", "Sander M.", "" ] ]
TITLE: Fast and Efficient Asynchronous Neural Computation with Adapting Spiking Neural Networks ABSTRACT: Biological neurons communicate with a sparing exchange of pulses - spikes. It is an open question how real spiking neurons produce the kind of powerful neural computation that is possible with deep artificial neural networks, using only so very few spikes to communicate. Building on recent insights in neuroscience, we present an Adapting Spiking Neural Network (ASNN) based on adaptive spiking neurons. These spiking neurons efficiently encode information in spike-trains using a form of Asynchronous Pulsed Sigma-Delta coding while homeostatically optimizing their firing rate. In the proposed paradigm of spiking neuron computation, neural adaptation is tightly coupled to synaptic plasticity, to ensure that downstream neurons can correctly decode upstream spiking neurons. We show that this type of network is inherently able to carry out asynchronous and event-driven neural computation, while performing identical to corresponding artificial neural networks (ANNs). In particular, we show that these adaptive spiking neurons can be drop in replacements for ReLU neurons in standard feedforward ANNs comprised of such units. We demonstrate that this can also be successfully applied to a ReLU based deep convolutional neural network for classifying the MNIST dataset. The ASNN thus outperforms current Spiking Neural Networks (SNNs) implementations, while responding (up to) an order of magnitude faster and using an order of magnitude fewer spikes. Additionally, in a streaming setting where frames are continuously classified, we show that the ASNN requires substantially fewer network updates as compared to the corresponding ANN.
no_new_dataset
0.949201
1608.04664
Stefanos Eleftheriadis
Stefanos Eleftheriadis, Ognjen Rudovic, Marc P. Deisenroth, Maja Pantic
Variational Gaussian Process Auto-Encoder for Ordinal Prediction of Facial Action Units
null
null
null
null
stat.ML cs.CV
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We address the task of simultaneous feature fusion and modeling of discrete ordinal outputs. We propose a novel Gaussian process(GP) auto-encoder modeling approach. In particular, we introduce GP encoders to project multiple observed features onto a latent space, while GP decoders are responsible for reconstructing the original features. Inference is performed in a novel variational framework, where the recovered latent representations are further constrained by the ordinal output labels. In this way, we seamlessly integrate the ordinal structure in the learned manifold, while attaining robust fusion of the input features. We demonstrate the representation abilities of our model on benchmark datasets from machine learning and affect analysis. We further evaluate the model on the tasks of feature fusion and joint ordinal prediction of facial action units. Our experiments demonstrate the benefits of the proposed approach compared to the state of the art.
[ { "version": "v1", "created": "Tue, 16 Aug 2016 16:31:39 GMT" }, { "version": "v2", "created": "Mon, 5 Sep 2016 21:25:48 GMT" } ]
2016-09-07T00:00:00
[ [ "Eleftheriadis", "Stefanos", "" ], [ "Rudovic", "Ognjen", "" ], [ "Deisenroth", "Marc P.", "" ], [ "Pantic", "Maja", "" ] ]
TITLE: Variational Gaussian Process Auto-Encoder for Ordinal Prediction of Facial Action Units ABSTRACT: We address the task of simultaneous feature fusion and modeling of discrete ordinal outputs. We propose a novel Gaussian process(GP) auto-encoder modeling approach. In particular, we introduce GP encoders to project multiple observed features onto a latent space, while GP decoders are responsible for reconstructing the original features. Inference is performed in a novel variational framework, where the recovered latent representations are further constrained by the ordinal output labels. In this way, we seamlessly integrate the ordinal structure in the learned manifold, while attaining robust fusion of the input features. We demonstrate the representation abilities of our model on benchmark datasets from machine learning and affect analysis. We further evaluate the model on the tasks of feature fusion and joint ordinal prediction of facial action units. Our experiments demonstrate the benefits of the proposed approach compared to the state of the art.
no_new_dataset
0.947672
1609.00489
Truyen Tran
Morakot Choetkiertikul, Hoa Khanh Dam, Truyen Tran, Trang Pham, Aditya Ghose and Tim Menzies
A deep learning model for estimating story points
Submitted to ICSE'17
null
null
null
cs.SE cs.LG stat.ML
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Although there has been substantial research in software analytics for effort estimation in traditional software projects, little work has been done for estimation in agile projects, especially estimating user stories or issues. Story points are the most common unit of measure used for estimating the effort involved in implementing a user story or resolving an issue. In this paper, we offer for the \emph{first} time a comprehensive dataset for story points-based estimation that contains 23,313 issues from 16 open source projects. We also propose a prediction model for estimating story points based on a novel combination of two powerful deep learning architectures: long short-term memory and recurrent highway network. Our prediction system is \emph{end-to-end} trainable from raw input data to prediction outcomes without any manual feature engineering. An empirical evaluation demonstrates that our approach consistently outperforms three common effort estimation baselines and two alternatives in both Mean Absolute Error and the Standardized Accuracy.
[ { "version": "v1", "created": "Fri, 2 Sep 2016 07:42:29 GMT" }, { "version": "v2", "created": "Tue, 6 Sep 2016 06:18:04 GMT" } ]
2016-09-07T00:00:00
[ [ "Choetkiertikul", "Morakot", "" ], [ "Dam", "Hoa Khanh", "" ], [ "Tran", "Truyen", "" ], [ "Pham", "Trang", "" ], [ "Ghose", "Aditya", "" ], [ "Menzies", "Tim", "" ] ]
TITLE: A deep learning model for estimating story points ABSTRACT: Although there has been substantial research in software analytics for effort estimation in traditional software projects, little work has been done for estimation in agile projects, especially estimating user stories or issues. Story points are the most common unit of measure used for estimating the effort involved in implementing a user story or resolving an issue. In this paper, we offer for the \emph{first} time a comprehensive dataset for story points-based estimation that contains 23,313 issues from 16 open source projects. We also propose a prediction model for estimating story points based on a novel combination of two powerful deep learning architectures: long short-term memory and recurrent highway network. Our prediction system is \emph{end-to-end} trainable from raw input data to prediction outcomes without any manual feature engineering. An empirical evaluation demonstrates that our approach consistently outperforms three common effort estimation baselines and two alternatives in both Mean Absolute Error and the Standardized Accuracy.
new_dataset
0.954942
1609.01326
Weichao Qiu
Weichao Qiu, Alan Yuille
UnrealCV: Connecting Computer Vision to Unreal Engine
null
null
null
null
cs.CV
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Computer graphics can not only generate synthetic images and ground truth but it also offers the possibility of constructing virtual worlds in which: (i) an agent can perceive, navigate, and take actions guided by AI algorithms, (ii) properties of the worlds can be modified (e.g., material and reflectance), (iii) physical simulations can be performed, and (iv) algorithms can be learnt and evaluated. But creating realistic virtual worlds is not easy. The game industry, however, has spent a lot of effort creating 3D worlds, which a player can interact with. So researchers can build on these resources to create virtual worlds, provided we can access and modify the internal data structures of the games. To enable this we created an open-source plugin UnrealCV (http://unrealcv.github.io) for a popular game engine Unreal Engine 4 (UE4). We show two applications: (i) a proof of concept image dataset, and (ii) linking Caffe with the virtual world to test deep network algorithms.
[ { "version": "v1", "created": "Mon, 5 Sep 2016 21:09:33 GMT" } ]
2016-09-07T00:00:00
[ [ "Qiu", "Weichao", "" ], [ "Yuille", "Alan", "" ] ]
TITLE: UnrealCV: Connecting Computer Vision to Unreal Engine ABSTRACT: Computer graphics can not only generate synthetic images and ground truth but it also offers the possibility of constructing virtual worlds in which: (i) an agent can perceive, navigate, and take actions guided by AI algorithms, (ii) properties of the worlds can be modified (e.g., material and reflectance), (iii) physical simulations can be performed, and (iv) algorithms can be learnt and evaluated. But creating realistic virtual worlds is not easy. The game industry, however, has spent a lot of effort creating 3D worlds, which a player can interact with. So researchers can build on these resources to create virtual worlds, provided we can access and modify the internal data structures of the games. To enable this we created an open-source plugin UnrealCV (http://unrealcv.github.io) for a popular game engine Unreal Engine 4 (UE4). We show two applications: (i) a proof of concept image dataset, and (ii) linking Caffe with the virtual world to test deep network algorithms.
new_dataset
0.894052
1609.01345
Andr\'as B\'odis-Szomor\'u
Andr\'as B\'odis-Szomor\'u, Hayko Riemenschneider, Luc Van Gool
Efficient Volumetric Fusion of Airborne and Street-Side Data for Urban Reconstruction
To appear in ICPR 2016
null
null
null
cs.CV
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Airborne acquisition and on-road mobile mapping provide complementary 3D information of an urban landscape: the former acquires roof structures, ground, and vegetation at a large scale, but lacks the facade and street-side details, while the latter is incomplete for higher floors and often totally misses out on pedestrian-only areas or undriven districts. In this work, we introduce an approach that efficiently unifies a detailed street-side Structure-from-Motion (SfM) or Multi-View Stereo (MVS) point cloud and a coarser but more complete point cloud from airborne acquisition in a joint surface mesh. We propose a point cloud blending and a volumetric fusion based on ray casting across a 3D tetrahedralization (3DT), extended with data reduction techniques to handle large datasets. To the best of our knowledge, we are the first to adopt a 3DT approach for airborne/street-side data fusion. Our pipeline exploits typical characteristics of airborne and ground data, and produces a seamless, watertight mesh that is both complete and detailed. Experiments on 3D urban data from multiple sources and different data densities show the effectiveness and benefits of our approach.
[ { "version": "v1", "created": "Mon, 5 Sep 2016 22:28:49 GMT" } ]
2016-09-07T00:00:00
[ [ "Bódis-Szomorú", "András", "" ], [ "Riemenschneider", "Hayko", "" ], [ "Van Gool", "Luc", "" ] ]
TITLE: Efficient Volumetric Fusion of Airborne and Street-Side Data for Urban Reconstruction ABSTRACT: Airborne acquisition and on-road mobile mapping provide complementary 3D information of an urban landscape: the former acquires roof structures, ground, and vegetation at a large scale, but lacks the facade and street-side details, while the latter is incomplete for higher floors and often totally misses out on pedestrian-only areas or undriven districts. In this work, we introduce an approach that efficiently unifies a detailed street-side Structure-from-Motion (SfM) or Multi-View Stereo (MVS) point cloud and a coarser but more complete point cloud from airborne acquisition in a joint surface mesh. We propose a point cloud blending and a volumetric fusion based on ray casting across a 3D tetrahedralization (3DT), extended with data reduction techniques to handle large datasets. To the best of our knowledge, we are the first to adopt a 3DT approach for airborne/street-side data fusion. Our pipeline exploits typical characteristics of airborne and ground data, and produces a seamless, watertight mesh that is both complete and detailed. Experiments on 3D urban data from multiple sources and different data densities show the effectiveness and benefits of our approach.
no_new_dataset
0.95418
1609.01388
Yale Song
Yale Song, Miriam Redi, Jordi Vallmitjana, Alejandro Jaimes
To Click or Not To Click: Automatic Selection of Beautiful Thumbnails from Videos
To appear in CIKM 2016
null
null
null
cs.MM
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Thumbnails play such an important role in online videos. As the most representative snapshot, they capture the essence of a video and provide the first impression to the viewers; ultimately, a great thumbnail makes a video more attractive to click and watch. We present an automatic thumbnail selection system that exploits two important characteristics commonly associated with meaningful and attractive thumbnails: high relevance to video content and superior visual aesthetic quality. Our system selects attractive thumbnails by analyzing various visual quality and aesthetic metrics of video frames, and performs a clustering analysis to determine the relevance to video content, thus making the resulting thumbnails more representative of the video. On the task of predicting thumbnails chosen by professional video editors, we demonstrate the effectiveness of our system against six baseline methods, using a real-world dataset of 1,118 videos collected from Yahoo Screen. In addition, we study what makes a frame a good thumbnail by analyzing the statistical relationship between thumbnail frames and non-thumbnail frames in terms of various image quality features. Our study suggests that the selection of a good thumbnail is highly correlated with objective visual quality metrics, such as the frame texture and sharpness, implying the possibility of building an automatic thumbnail selection system based on visual aesthetics.
[ { "version": "v1", "created": "Tue, 6 Sep 2016 04:33:34 GMT" } ]
2016-09-07T00:00:00
[ [ "Song", "Yale", "" ], [ "Redi", "Miriam", "" ], [ "Vallmitjana", "Jordi", "" ], [ "Jaimes", "Alejandro", "" ] ]
TITLE: To Click or Not To Click: Automatic Selection of Beautiful Thumbnails from Videos ABSTRACT: Thumbnails play such an important role in online videos. As the most representative snapshot, they capture the essence of a video and provide the first impression to the viewers; ultimately, a great thumbnail makes a video more attractive to click and watch. We present an automatic thumbnail selection system that exploits two important characteristics commonly associated with meaningful and attractive thumbnails: high relevance to video content and superior visual aesthetic quality. Our system selects attractive thumbnails by analyzing various visual quality and aesthetic metrics of video frames, and performs a clustering analysis to determine the relevance to video content, thus making the resulting thumbnails more representative of the video. On the task of predicting thumbnails chosen by professional video editors, we demonstrate the effectiveness of our system against six baseline methods, using a real-world dataset of 1,118 videos collected from Yahoo Screen. In addition, we study what makes a frame a good thumbnail by analyzing the statistical relationship between thumbnail frames and non-thumbnail frames in terms of various image quality features. Our study suggests that the selection of a good thumbnail is highly correlated with objective visual quality metrics, such as the frame texture and sharpness, implying the possibility of building an automatic thumbnail selection system based on visual aesthetics.
no_new_dataset
0.932699
1609.01414
Vinay Kumar N
N. Vinay Kumar, Pratheek, V. Vijaya Kantha, K. N. Govindaraju, and D. S. Guru
Features Fusion for Classification of Logos
10 pages, 5 figures, 9 tables
Procedia Computer Science, Volume 85, 2016, Pages 370-379
10.1016/j.procs.2016.05.245
null
cs.CV
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
In this paper, a logo classification system based on the appearance of logo images is proposed. The proposed classification system makes use of global characteristics of logo images for classification. Color, texture, and shape of a logo wholly describe the global characteristics of logo images. The various combinations of these characteristics are used for classification. The combination contains only with single feature or with fusion of two features or fusion of all three features considered at a time respectively. Further, the system categorizes the logo image into: a logo image with fully text or with fully symbols or containing both symbols and texts.. The K-Nearest Neighbour (K-NN) classifier is used for classification. Due to the lack of color logo image dataset in the literature, the same is created consisting 5044 color logo images. Finally, the performance of the classification system is evaluated through accuracy, precision, recall and F-measure computed from the confusion matrix. The experimental results show that the most promising results are obtained for fusion of features.
[ { "version": "v1", "created": "Tue, 6 Sep 2016 07:29:56 GMT" } ]
2016-09-07T00:00:00
[ [ "Kumar", "N. Vinay", "" ], [ "Pratheek", "", "" ], [ "Kantha", "V. Vijaya", "" ], [ "Govindaraju", "K. N.", "" ], [ "Guru", "D. S.", "" ] ]
TITLE: Features Fusion for Classification of Logos ABSTRACT: In this paper, a logo classification system based on the appearance of logo images is proposed. The proposed classification system makes use of global characteristics of logo images for classification. Color, texture, and shape of a logo wholly describe the global characteristics of logo images. The various combinations of these characteristics are used for classification. The combination contains only with single feature or with fusion of two features or fusion of all three features considered at a time respectively. Further, the system categorizes the logo image into: a logo image with fully text or with fully symbols or containing both symbols and texts.. The K-Nearest Neighbour (K-NN) classifier is used for classification. Due to the lack of color logo image dataset in the literature, the same is created consisting 5044 color logo images. Finally, the performance of the classification system is evaluated through accuracy, precision, recall and F-measure computed from the confusion matrix. The experimental results show that the most promising results are obtained for fusion of features.
no_new_dataset
0.867934
1609.01483
Sverre Holm
Saeed Mehdizadeh, Sebastien Muller, Gabriel Kiss, Tonni F. Johansen, and Sverre Holm
Joint Beamforming and Feature Detection for Enhanced Visualization of Spinal Bone Surfaces in Ultrasound Images
12 figures
null
null
null
physics.med-ph physics.bio-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We propose a framework for extracting the bone surface from B-mode images employing the eigenspace minimum variance (ESMV) beamformer and a ridge detection method. We show that an ESMV beamformer with a rank-1 signal subspace can preserve the bone anatomy and enhance the edges, despite an image which is less visually appealing due to some speckle pattern distortion. The beamformed images are post-processed using the phase symmetry (PS) technique. We validate this framework by registering the ultrasound images of a vertebra (in a water bath) against the corresponding Computed Tomography (CT) dataset. The results show a bone localization error in the same order of magnitude as the standard delay-and-sum (DAS) technique, but with approximately 20% smaller standard deviation (STD) of the image intensity distribution around the bone surface. This indicates a sharper bone surface detection. Further, the noise level inside the bone shadow is reduced by 60%. In in-vivo experiments, this framework is used for imaging the spinal anatomy. We show that PS images obtained from this beamformer setup have sharper bone boundaries in comparison with the standard DAS ones, and they are reasonably well separated from the surrounding soft tissue.
[ { "version": "v1", "created": "Tue, 6 Sep 2016 10:56:13 GMT" } ]
2016-09-07T00:00:00
[ [ "Mehdizadeh", "Saeed", "" ], [ "Muller", "Sebastien", "" ], [ "Kiss", "Gabriel", "" ], [ "Johansen", "Tonni F.", "" ], [ "Holm", "Sverre", "" ] ]
TITLE: Joint Beamforming and Feature Detection for Enhanced Visualization of Spinal Bone Surfaces in Ultrasound Images ABSTRACT: We propose a framework for extracting the bone surface from B-mode images employing the eigenspace minimum variance (ESMV) beamformer and a ridge detection method. We show that an ESMV beamformer with a rank-1 signal subspace can preserve the bone anatomy and enhance the edges, despite an image which is less visually appealing due to some speckle pattern distortion. The beamformed images are post-processed using the phase symmetry (PS) technique. We validate this framework by registering the ultrasound images of a vertebra (in a water bath) against the corresponding Computed Tomography (CT) dataset. The results show a bone localization error in the same order of magnitude as the standard delay-and-sum (DAS) technique, but with approximately 20% smaller standard deviation (STD) of the image intensity distribution around the bone surface. This indicates a sharper bone surface detection. Further, the noise level inside the bone shadow is reduced by 60%. In in-vivo experiments, this framework is used for imaging the spinal anatomy. We show that PS images obtained from this beamformer setup have sharper bone boundaries in comparison with the standard DAS ones, and they are reasonably well separated from the surrounding soft tissue.
no_new_dataset
0.955981
1609.01484
Sujoy Chatterjee
Sujoy Chatterjee, Enakshi Kundu and Anirban Mukhopadhyay
A Markov Chain based Ensemble Method for Crowdsourced Clustering
Works in Progress, Fourth AAAI Conference on Human Computation and Crowdsourcing (HCOMP 2016), Austin, TX, USA
null
null
null
cs.HC cs.SI
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
In presence of multiple clustering solutions for the same dataset, a clustering ensemble approach aims to yield a single clustering of the dataset by achieving a consensus among the input clustering solutions. The goal of this consensus is to improve the quality of clustering. It has been seen that there are some image clustering tasks that cannot be easily solved by computer. But if these images can be outsourced to the general people (crowd workers) to group them based on some similar features, and opinions are collected from them, then this task can be managed in an efficient manner and time effective way. In this work, the power of crowd has been used to annotate the images so that multiple clustering solutions can be obtained from them and thereafter a Markov chain based ensemble method is introduced to make a consensus of multiple clustering solutions.
[ { "version": "v1", "created": "Tue, 6 Sep 2016 10:58:34 GMT" } ]
2016-09-07T00:00:00
[ [ "Chatterjee", "Sujoy", "" ], [ "Kundu", "Enakshi", "" ], [ "Mukhopadhyay", "Anirban", "" ] ]
TITLE: A Markov Chain based Ensemble Method for Crowdsourced Clustering ABSTRACT: In presence of multiple clustering solutions for the same dataset, a clustering ensemble approach aims to yield a single clustering of the dataset by achieving a consensus among the input clustering solutions. The goal of this consensus is to improve the quality of clustering. It has been seen that there are some image clustering tasks that cannot be easily solved by computer. But if these images can be outsourced to the general people (crowd workers) to group them based on some similar features, and opinions are collected from them, then this task can be managed in an efficient manner and time effective way. In this work, the power of crowd has been used to annotate the images so that multiple clustering solutions can be obtained from them and thereafter a Markov chain based ensemble method is introduced to make a consensus of multiple clustering solutions.
no_new_dataset
0.951729
1609.01571
Shaul Oron
Shaul Oron, Tali Dekel, Tianfan Xue, William T. Freeman, Shai Avidan
Best-Buddies Similarity - Robust Template Matching using Mutual Nearest Neighbors
null
null
null
null
cs.CV
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We propose a novel method for template matching in unconstrained environments. Its essence is the Best-Buddies Similarity (BBS), a useful, robust, and parameter-free similarity measure between two sets of points. BBS is based on counting the number of Best-Buddies Pairs (BBPs)--pairs of points in source and target sets, where each point is the nearest neighbor of the other. BBS has several key features that make it robust against complex geometric deformations and high levels of outliers, such as those arising from background clutter and occlusions. We study these properties, provide a statistical analysis that justifies them, and demonstrate the consistent success of BBS on a challenging real-world dataset while using different types of features.
[ { "version": "v1", "created": "Tue, 6 Sep 2016 14:24:36 GMT" } ]
2016-09-07T00:00:00
[ [ "Oron", "Shaul", "" ], [ "Dekel", "Tali", "" ], [ "Xue", "Tianfan", "" ], [ "Freeman", "William T.", "" ], [ "Avidan", "Shai", "" ] ]
TITLE: Best-Buddies Similarity - Robust Template Matching using Mutual Nearest Neighbors ABSTRACT: We propose a novel method for template matching in unconstrained environments. Its essence is the Best-Buddies Similarity (BBS), a useful, robust, and parameter-free similarity measure between two sets of points. BBS is based on counting the number of Best-Buddies Pairs (BBPs)--pairs of points in source and target sets, where each point is the nearest neighbor of the other. BBS has several key features that make it robust against complex geometric deformations and high levels of outliers, such as those arising from background clutter and occlusions. We study these properties, provide a statistical analysis that justifies them, and demonstrate the consistent success of BBS on a challenging real-world dataset while using different types of features.
no_new_dataset
0.953923
1601.04485
Jose Velasco
Jose Velasco, Daniel Pizarro, Javier Macias-Guarasa and Afsaneh Asaei
TDOA Matrices: Algebraic Properties and their Application to Robust Denoising with Missing Data
null
IEEE Transactions on Signal Processing ( Volume: 64, Issue: 20, Oct.15, 15 2016 )
10.1109/TSP.2016.2593690
null
cs.IT math.IT
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Measuring the Time delay of Arrival (TDOA) between a set of sensors is the basic setup for many applications, such as localization or signal beamforming. This paper presents the set of TDOA matrices, which are built from noise-free TDOA measurements, not requiring knowledge of the sensor array geometry. We prove that TDOA matrices are rank-two and have a special SVD decomposition that leads to a compact linear parametric representation. Properties of TDOA matrices are applied in this paper to perform denoising, by finding the TDOA matrix closest to the matrix composed with noisy measurements. The paper shows that this problem admits a closed-form solution for TDOA measurements contaminated with Gaussian noise which extends to the case of having missing data. The paper also proposes a novel robust denoising method resistant to outliers, missing data and inspired in recent advances in robust low-rank estimation. Experiments in synthetic and real datasets show TDOA-based localization, both in terms of TDOA accuracy estimation and localization error.
[ { "version": "v1", "created": "Mon, 18 Jan 2016 12:01:45 GMT" }, { "version": "v2", "created": "Tue, 24 May 2016 14:00:01 GMT" } ]
2016-09-06T00:00:00
[ [ "Velasco", "Jose", "" ], [ "Pizarro", "Daniel", "" ], [ "Macias-Guarasa", "Javier", "" ], [ "Asaei", "Afsaneh", "" ] ]
TITLE: TDOA Matrices: Algebraic Properties and their Application to Robust Denoising with Missing Data ABSTRACT: Measuring the Time delay of Arrival (TDOA) between a set of sensors is the basic setup for many applications, such as localization or signal beamforming. This paper presents the set of TDOA matrices, which are built from noise-free TDOA measurements, not requiring knowledge of the sensor array geometry. We prove that TDOA matrices are rank-two and have a special SVD decomposition that leads to a compact linear parametric representation. Properties of TDOA matrices are applied in this paper to perform denoising, by finding the TDOA matrix closest to the matrix composed with noisy measurements. The paper shows that this problem admits a closed-form solution for TDOA measurements contaminated with Gaussian noise which extends to the case of having missing data. The paper also proposes a novel robust denoising method resistant to outliers, missing data and inspired in recent advances in robust low-rank estimation. Experiments in synthetic and real datasets show TDOA-based localization, both in terms of TDOA accuracy estimation and localization error.
no_new_dataset
0.940517