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1511.06739
Varun Jampani
Raghudeep Gadde and Varun Jampani and Martin Kiefel and Daniel Kappler and Peter V. Gehler
Superpixel Convolutional Networks using Bilateral Inceptions
European Conference on Computer Vision (ECCV), 2016
null
null
null
cs.CV
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
In this paper we propose a CNN architecture for semantic image segmentation. We introduce a new 'bilateral inception' module that can be inserted in existing CNN architectures and performs bilateral filtering, at multiple feature-scales, between superpixels in an image. The feature spaces for bilateral filtering and other parameters of the module are learned end-to-end using standard backpropagation techniques. The bilateral inception module addresses two issues that arise with general CNN segmentation architectures. First, this module propagates information between (super) pixels while respecting image edges, thus using the structured information of the problem for improved results. Second, the layer recovers a full resolution segmentation result from the lower resolution solution of a CNN. In the experiments, we modify several existing CNN architectures by inserting our inception module between the last CNN (1x1 convolution) layers. Empirical results on three different datasets show reliable improvements not only in comparison to the baseline networks, but also in comparison to several dense-pixel prediction techniques such as CRFs, while being competitive in time.
[ { "version": "v1", "created": "Fri, 20 Nov 2015 19:58:38 GMT" }, { "version": "v2", "created": "Sat, 12 Dec 2015 10:43:52 GMT" }, { "version": "v3", "created": "Fri, 8 Jan 2016 09:10:31 GMT" }, { "version": "v4", "created": "Fri, 5 Aug 2016 09:14:18 GMT" }, { "version": "v5", "created": "Mon, 8 Aug 2016 15:31:14 GMT" } ]
2016-08-09T00:00:00
[ [ "Gadde", "Raghudeep", "" ], [ "Jampani", "Varun", "" ], [ "Kiefel", "Martin", "" ], [ "Kappler", "Daniel", "" ], [ "Gehler", "Peter V.", "" ] ]
TITLE: Superpixel Convolutional Networks using Bilateral Inceptions ABSTRACT: In this paper we propose a CNN architecture for semantic image segmentation. We introduce a new 'bilateral inception' module that can be inserted in existing CNN architectures and performs bilateral filtering, at multiple feature-scales, between superpixels in an image. The feature spaces for bilateral filtering and other parameters of the module are learned end-to-end using standard backpropagation techniques. The bilateral inception module addresses two issues that arise with general CNN segmentation architectures. First, this module propagates information between (super) pixels while respecting image edges, thus using the structured information of the problem for improved results. Second, the layer recovers a full resolution segmentation result from the lower resolution solution of a CNN. In the experiments, we modify several existing CNN architectures by inserting our inception module between the last CNN (1x1 convolution) layers. Empirical results on three different datasets show reliable improvements not only in comparison to the baseline networks, but also in comparison to several dense-pixel prediction techniques such as CRFs, while being competitive in time.
no_new_dataset
0.951684
1511.07710
Varun Nagaraja
Varun K. Nagaraja, Vlad I. Morariu, Larry S. Davis
Searching for Objects using Structure in Indoor Scenes
Appeared in British Machine Vision Conference (BMVC) 2015
null
10.5244/C.29.53
null
cs.CV cs.AI
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
To identify the location of objects of a particular class, a passive computer vision system generally processes all the regions in an image to finally output few regions. However, we can use structure in the scene to search for objects without processing the entire image. We propose a search technique that sequentially processes image regions such that the regions that are more likely to correspond to the query class object are explored earlier. We frame the problem as a Markov decision process and use an imitation learning algorithm to learn a search strategy. Since structure in the scene is essential for search, we work with indoor scene images as they contain both unary scene context information and object-object context in the scene. We perform experiments on the NYU-depth v2 dataset and show that the unary scene context features alone can achieve a significantly high average precision while processing only 20-25\% of the regions for classes like bed and sofa. By considering object-object context along with the scene context features, the performance is further improved for classes like counter, lamp, pillow and sofa.
[ { "version": "v1", "created": "Tue, 24 Nov 2015 14:05:28 GMT" } ]
2016-08-09T00:00:00
[ [ "Nagaraja", "Varun K.", "" ], [ "Morariu", "Vlad I.", "" ], [ "Davis", "Larry S.", "" ] ]
TITLE: Searching for Objects using Structure in Indoor Scenes ABSTRACT: To identify the location of objects of a particular class, a passive computer vision system generally processes all the regions in an image to finally output few regions. However, we can use structure in the scene to search for objects without processing the entire image. We propose a search technique that sequentially processes image regions such that the regions that are more likely to correspond to the query class object are explored earlier. We frame the problem as a Markov decision process and use an imitation learning algorithm to learn a search strategy. Since structure in the scene is essential for search, we work with indoor scene images as they contain both unary scene context information and object-object context in the scene. We perform experiments on the NYU-depth v2 dataset and show that the unary scene context features alone can achieve a significantly high average precision while processing only 20-25\% of the regions for classes like bed and sofa. By considering object-object context along with the scene context features, the performance is further improved for classes like counter, lamp, pillow and sofa.
no_new_dataset
0.957833
1512.06285
Min Xian
Min Xian, Yingtao Zhang, H. D. Cheng, Fei Xu, Jianrui Ding
Neutro-Connectedness Cut
15 pages, 14 figures, 4 tables, journal
null
10.1109/TIP.2016.2594485
null
cs.CV
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Interactive image segmentation is a challenging task and receives increasing attention recently; however, two major drawbacks exist in interactive segmentation approaches. First, the segmentation performance of ROI-based methods is sensitive to the initial ROI: different ROIs may produce results with great difference. Second, most seed-based methods need intense interactions, and are not applicable in many cases. In this work, we generalize the Neutro-Connectedness (NC) to be independent of top-down priors of objects and to model image topology with indeterminacy measurement on image regions, propose a novel method for determining object and background regions, which is applied to exclude isolated background regions and enforce label consistency, and put forward a hybrid interactive segmentation method, Neutro-Connectedness Cut (NC-Cut), which can overcome the above two problems by utilizing both pixel-wise appearance information and region-based NC properties. We evaluate the proposed NC-Cut by employing two image datasets (265 images), and demonstrate that the proposed approach outperforms state-of-the-art interactive image segmentation methods (Grabcut, MILCut, One-Cut, MGC_max^sum and pPBC).
[ { "version": "v1", "created": "Sat, 19 Dec 2015 20:59:09 GMT" }, { "version": "v2", "created": "Sat, 6 Aug 2016 04:51:06 GMT" } ]
2016-08-09T00:00:00
[ [ "Xian", "Min", "" ], [ "Zhang", "Yingtao", "" ], [ "Cheng", "H. D.", "" ], [ "Xu", "Fei", "" ], [ "Ding", "Jianrui", "" ] ]
TITLE: Neutro-Connectedness Cut ABSTRACT: Interactive image segmentation is a challenging task and receives increasing attention recently; however, two major drawbacks exist in interactive segmentation approaches. First, the segmentation performance of ROI-based methods is sensitive to the initial ROI: different ROIs may produce results with great difference. Second, most seed-based methods need intense interactions, and are not applicable in many cases. In this work, we generalize the Neutro-Connectedness (NC) to be independent of top-down priors of objects and to model image topology with indeterminacy measurement on image regions, propose a novel method for determining object and background regions, which is applied to exclude isolated background regions and enforce label consistency, and put forward a hybrid interactive segmentation method, Neutro-Connectedness Cut (NC-Cut), which can overcome the above two problems by utilizing both pixel-wise appearance information and region-based NC properties. We evaluate the proposed NC-Cut by employing two image datasets (265 images), and demonstrate that the proposed approach outperforms state-of-the-art interactive image segmentation methods (Grabcut, MILCut, One-Cut, MGC_max^sum and pPBC).
no_new_dataset
0.947962
1601.01145
Yiren Zhou
Yiren Zhou, Hossein Nejati, Thanh-Toan Do, Ngai-Man Cheung, Lynette Cheah
Image-based Vehicle Analysis using Deep Neural Network: A Systematic Study
5 pages, 6 figures, conference
null
null
null
cs.CV
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We address the vehicle detection and classification problems using Deep Neural Networks (DNNs) approaches. Here we answer to questions that are specific to our application including how to utilize DNN for vehicle detection, what features are useful for vehicle classification, and how to extend a model trained on a limited size dataset, to the cases of extreme lighting condition. Answering these questions we propose our approach that outperforms state-of-the-art methods, and achieves promising results on image with extreme lighting conditions.
[ { "version": "v1", "created": "Wed, 6 Jan 2016 11:25:36 GMT" }, { "version": "v2", "created": "Sun, 7 Aug 2016 09:21:08 GMT" } ]
2016-08-09T00:00:00
[ [ "Zhou", "Yiren", "" ], [ "Nejati", "Hossein", "" ], [ "Do", "Thanh-Toan", "" ], [ "Cheung", "Ngai-Man", "" ], [ "Cheah", "Lynette", "" ] ]
TITLE: Image-based Vehicle Analysis using Deep Neural Network: A Systematic Study ABSTRACT: We address the vehicle detection and classification problems using Deep Neural Networks (DNNs) approaches. Here we answer to questions that are specific to our application including how to utilize DNN for vehicle detection, what features are useful for vehicle classification, and how to extend a model trained on a limited size dataset, to the cases of extreme lighting condition. Answering these questions we propose our approach that outperforms state-of-the-art methods, and achieves promising results on image with extreme lighting conditions.
no_new_dataset
0.950273
1603.06098
Alexander Kolesnikov
Alexander Kolesnikov and Christoph H. Lampert
Seed, Expand and Constrain: Three Principles for Weakly-Supervised Image Segmentation
ECCV 2016
null
null
null
cs.CV
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We introduce a new loss function for the weakly-supervised training of semantic image segmentation models based on three guiding principles: to seed with weak localization cues, to expand objects based on the information about which classes can occur in an image, and to constrain the segmentations to coincide with object boundaries. We show experimentally that training a deep convolutional neural network using the proposed loss function leads to substantially better segmentations than previous state-of-the-art methods on the challenging PASCAL VOC 2012 dataset. We furthermore give insight into the working mechanism of our method by a detailed experimental study that illustrates how the segmentation quality is affected by each term of the proposed loss function as well as their combinations.
[ { "version": "v1", "created": "Sat, 19 Mar 2016 14:13:42 GMT" }, { "version": "v2", "created": "Mon, 25 Jul 2016 17:36:50 GMT" }, { "version": "v3", "created": "Sat, 6 Aug 2016 18:49:45 GMT" } ]
2016-08-09T00:00:00
[ [ "Kolesnikov", "Alexander", "" ], [ "Lampert", "Christoph H.", "" ] ]
TITLE: Seed, Expand and Constrain: Three Principles for Weakly-Supervised Image Segmentation ABSTRACT: We introduce a new loss function for the weakly-supervised training of semantic image segmentation models based on three guiding principles: to seed with weak localization cues, to expand objects based on the information about which classes can occur in an image, and to constrain the segmentations to coincide with object boundaries. We show experimentally that training a deep convolutional neural network using the proposed loss function leads to substantially better segmentations than previous state-of-the-art methods on the challenging PASCAL VOC 2012 dataset. We furthermore give insight into the working mechanism of our method by a detailed experimental study that illustrates how the segmentation quality is affected by each term of the proposed loss function as well as their combinations.
no_new_dataset
0.95018
1604.02135
Sergey Zagoruyko
Sergey Zagoruyko, Adam Lerer, Tsung-Yi Lin, Pedro O. Pinheiro, Sam Gross, Soumith Chintala, Piotr Doll\'ar
A MultiPath Network for Object Detection
null
null
null
null
cs.CV
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The recent COCO object detection dataset presents several new challenges for object detection. In particular, it contains objects at a broad range of scales, less prototypical images, and requires more precise localization. To address these challenges, we test three modifications to the standard Fast R-CNN object detector: (1) skip connections that give the detector access to features at multiple network layers, (2) a foveal structure to exploit object context at multiple object resolutions, and (3) an integral loss function and corresponding network adjustment that improve localization. The result of these modifications is that information can flow along multiple paths in our network, including through features from multiple network layers and from multiple object views. We refer to our modified classifier as a "MultiPath" network. We couple our MultiPath network with DeepMask object proposals, which are well suited for localization and small objects, and adapt our pipeline to predict segmentation masks in addition to bounding boxes. The combined system improves results over the baseline Fast R-CNN detector with Selective Search by 66% overall and by 4x on small objects. It placed second in both the COCO 2015 detection and segmentation challenges.
[ { "version": "v1", "created": "Thu, 7 Apr 2016 19:43:47 GMT" }, { "version": "v2", "created": "Mon, 8 Aug 2016 13:29:02 GMT" } ]
2016-08-09T00:00:00
[ [ "Zagoruyko", "Sergey", "" ], [ "Lerer", "Adam", "" ], [ "Lin", "Tsung-Yi", "" ], [ "Pinheiro", "Pedro O.", "" ], [ "Gross", "Sam", "" ], [ "Chintala", "Soumith", "" ], [ "Dollár", "Piotr", "" ] ]
TITLE: A MultiPath Network for Object Detection ABSTRACT: The recent COCO object detection dataset presents several new challenges for object detection. In particular, it contains objects at a broad range of scales, less prototypical images, and requires more precise localization. To address these challenges, we test three modifications to the standard Fast R-CNN object detector: (1) skip connections that give the detector access to features at multiple network layers, (2) a foveal structure to exploit object context at multiple object resolutions, and (3) an integral loss function and corresponding network adjustment that improve localization. The result of these modifications is that information can flow along multiple paths in our network, including through features from multiple network layers and from multiple object views. We refer to our modified classifier as a "MultiPath" network. We couple our MultiPath network with DeepMask object proposals, which are well suited for localization and small objects, and adapt our pipeline to predict segmentation masks in addition to bounding boxes. The combined system improves results over the baseline Fast R-CNN detector with Selective Search by 66% overall and by 4x on small objects. It placed second in both the COCO 2015 detection and segmentation challenges.
no_new_dataset
0.955817
1605.00164
Dinesh Jayaraman
Dinesh Jayaraman and Kristen Grauman
Look-ahead before you leap: end-to-end active recognition by forecasting the effect of motion
A preliminary version of the material in this document was filed as University of Texas technical report no. UT AI15-06, December, 2015, at: http://apps.cs.utexas.edu/tech_reports/reports/ai/AI-2214.pdf, ECCV 2016
null
null
University of Texas Technical Report UT AI 15-06 (December 2015)
cs.CV cs.AI cs.LG cs.RO
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Visual recognition systems mounted on autonomous moving agents face the challenge of unconstrained data, but simultaneously have the opportunity to improve their performance by moving to acquire new views of test data. In this work, we first show how a recurrent neural network-based system may be trained to perform end-to-end learning of motion policies suited for this "active recognition" setting. Further, we hypothesize that active vision requires an agent to have the capacity to reason about the effects of its motions on its view of the world. To verify this hypothesis, we attempt to induce this capacity in our active recognition pipeline, by simultaneously learning to forecast the effects of the agent's motions on its internal representation of the environment conditional on all past views. Results across two challenging datasets confirm both that our end-to-end system successfully learns meaningful policies for active category recognition, and that "learning to look ahead" further boosts recognition performance.
[ { "version": "v1", "created": "Sat, 30 Apr 2016 20:39:16 GMT" }, { "version": "v2", "created": "Fri, 5 Aug 2016 22:15:48 GMT" } ]
2016-08-09T00:00:00
[ [ "Jayaraman", "Dinesh", "" ], [ "Grauman", "Kristen", "" ] ]
TITLE: Look-ahead before you leap: end-to-end active recognition by forecasting the effect of motion ABSTRACT: Visual recognition systems mounted on autonomous moving agents face the challenge of unconstrained data, but simultaneously have the opportunity to improve their performance by moving to acquire new views of test data. In this work, we first show how a recurrent neural network-based system may be trained to perform end-to-end learning of motion policies suited for this "active recognition" setting. Further, we hypothesize that active vision requires an agent to have the capacity to reason about the effects of its motions on its view of the world. To verify this hypothesis, we attempt to induce this capacity in our active recognition pipeline, by simultaneously learning to forecast the effects of the agent's motions on its internal representation of the environment conditional on all past views. Results across two challenging datasets confirm both that our end-to-end system successfully learns meaningful policies for active category recognition, and that "learning to look ahead" further boosts recognition performance.
no_new_dataset
0.950088
1608.02010
Si Si
Cho-Jui Hsieh and Si Si and Inderjit S. Dhillon
Communication-Efficient Parallel Block Minimization for Kernel Machines
null
null
null
null
cs.LG
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Kernel machines often yield superior predictive performance on various tasks; however, they suffer from severe computational challenges. In this paper, we show how to overcome the important challenge of speeding up kernel machines. In particular, we develop a parallel block minimization framework for solving kernel machines, including kernel SVM and kernel logistic regression. Our framework proceeds by dividing the problem into smaller subproblems by forming a block-diagonal approximation of the Hessian matrix. The subproblems are then solved approximately in parallel. After that, a communication efficient line search procedure is developed to ensure sufficient reduction of the objective function value at each iteration. We prove global linear convergence rate of the proposed method with a wide class of subproblem solvers, and our analysis covers strongly convex and some non-strongly convex functions. We apply our algorithm to solve large-scale kernel SVM problems on distributed systems, and show a significant improvement over existing parallel solvers. As an example, on the covtype dataset with half-a-million samples, our algorithm can obtain an approximate solution with 96% accuracy in 20 seconds using 32 machines, while all the other parallel kernel SVM solvers require more than 2000 seconds to achieve a solution with 95% accuracy. Moreover, our algorithm can scale to very large data sets, such as the kdd algebra dataset with 8 million samples and 20 million features.
[ { "version": "v1", "created": "Fri, 5 Aug 2016 20:15:51 GMT" } ]
2016-08-09T00:00:00
[ [ "Hsieh", "Cho-Jui", "" ], [ "Si", "Si", "" ], [ "Dhillon", "Inderjit S.", "" ] ]
TITLE: Communication-Efficient Parallel Block Minimization for Kernel Machines ABSTRACT: Kernel machines often yield superior predictive performance on various tasks; however, they suffer from severe computational challenges. In this paper, we show how to overcome the important challenge of speeding up kernel machines. In particular, we develop a parallel block minimization framework for solving kernel machines, including kernel SVM and kernel logistic regression. Our framework proceeds by dividing the problem into smaller subproblems by forming a block-diagonal approximation of the Hessian matrix. The subproblems are then solved approximately in parallel. After that, a communication efficient line search procedure is developed to ensure sufficient reduction of the objective function value at each iteration. We prove global linear convergence rate of the proposed method with a wide class of subproblem solvers, and our analysis covers strongly convex and some non-strongly convex functions. We apply our algorithm to solve large-scale kernel SVM problems on distributed systems, and show a significant improvement over existing parallel solvers. As an example, on the covtype dataset with half-a-million samples, our algorithm can obtain an approximate solution with 96% accuracy in 20 seconds using 32 machines, while all the other parallel kernel SVM solvers require more than 2000 seconds to achieve a solution with 95% accuracy. Moreover, our algorithm can scale to very large data sets, such as the kdd algebra dataset with 8 million samples and 20 million features.
no_new_dataset
0.946051
1608.02026
Hatem Alismail
Hatem Alismail and Brett Browning and Simon Lucey
Photometric Bundle Adjustment for Vision-Based SLAM
Under review
null
null
null
cs.CV cs.RO
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We propose a novel algorithm for the joint refinement of structure and motion parameters from image data directly without relying on fixed and known correspondences. In contrast to traditional bundle adjustment (BA) where the optimal parameters are determined by minimizing the reprojection error using tracked features, the proposed algorithm relies on maximizing the photometric consistency and estimates the correspondences implicitly. Since the proposed algorithm does not require correspondences, its application is not limited to corner-like structure; any pixel with nonvanishing gradient could be used in the estimation process. Furthermore, we demonstrate the feasibility of refining the motion and structure parameters simultaneously using the photometric in unconstrained scenes and without requiring restrictive assumptions such as planarity. The proposed algorithm is evaluated on range of challenging outdoor datasets, and it is shown to improve upon the accuracy of the state-of-the-art VSLAM methods obtained using the minimization of the reprojection error using traditional BA as well as loop closure.
[ { "version": "v1", "created": "Fri, 5 Aug 2016 21:27:11 GMT" } ]
2016-08-09T00:00:00
[ [ "Alismail", "Hatem", "" ], [ "Browning", "Brett", "" ], [ "Lucey", "Simon", "" ] ]
TITLE: Photometric Bundle Adjustment for Vision-Based SLAM ABSTRACT: We propose a novel algorithm for the joint refinement of structure and motion parameters from image data directly without relying on fixed and known correspondences. In contrast to traditional bundle adjustment (BA) where the optimal parameters are determined by minimizing the reprojection error using tracked features, the proposed algorithm relies on maximizing the photometric consistency and estimates the correspondences implicitly. Since the proposed algorithm does not require correspondences, its application is not limited to corner-like structure; any pixel with nonvanishing gradient could be used in the estimation process. Furthermore, we demonstrate the feasibility of refining the motion and structure parameters simultaneously using the photometric in unconstrained scenes and without requiring restrictive assumptions such as planarity. The proposed algorithm is evaluated on range of challenging outdoor datasets, and it is shown to improve upon the accuracy of the state-of-the-art VSLAM methods obtained using the minimization of the reprojection error using traditional BA as well as loop closure.
no_new_dataset
0.949435
1608.02051
Kanji Tanaka
Tomoya Murase and Kanji Tanaka
Compressive Change Retrieval for Moving Object Detection
6 pages, 6 figures, Draft of a paper submitted to an International Conference
null
null
null
cs.CV
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Change detection, or anomaly detection, from street-view images acquired by an autonomous robot at multiple different times, is a major problem in robotic mapping and autonomous driving. Formulation as an image comparison task, which operates on a given pair of query and reference images is common to many existing approaches to this problem. Unfortunately, providing relevant reference images is not straightforward. In this paper, we propose a novel formulation for change detection, termed compressive change retrieval, which can operate on a query image and similar reference images retrieved from the web. Compared to previous formulations, there are two sources of difficulty. First, the retrieved reference images may frequently contain non-relevant reference images, because even state-of-the-art place-recognition techniques suffer from retrieval noise. Second, image comparison needs to be conducted in a compressed domain to minimize the storage cost of large collections of street-view images. To address the above issues, we also present a practical change detection algorithm that uses compressed bag-of-words (BoW) image representation as a scalable solution. The results of experiments conducted on a practical change detection task, "moving object detection (MOD)," using the publicly available Malaga dataset validate the effectiveness of the proposed approach.
[ { "version": "v1", "created": "Sat, 6 Aug 2016 02:04:25 GMT" } ]
2016-08-09T00:00:00
[ [ "Murase", "Tomoya", "" ], [ "Tanaka", "Kanji", "" ] ]
TITLE: Compressive Change Retrieval for Moving Object Detection ABSTRACT: Change detection, or anomaly detection, from street-view images acquired by an autonomous robot at multiple different times, is a major problem in robotic mapping and autonomous driving. Formulation as an image comparison task, which operates on a given pair of query and reference images is common to many existing approaches to this problem. Unfortunately, providing relevant reference images is not straightforward. In this paper, we propose a novel formulation for change detection, termed compressive change retrieval, which can operate on a query image and similar reference images retrieved from the web. Compared to previous formulations, there are two sources of difficulty. First, the retrieved reference images may frequently contain non-relevant reference images, because even state-of-the-art place-recognition techniques suffer from retrieval noise. Second, image comparison needs to be conducted in a compressed domain to minimize the storage cost of large collections of street-view images. To address the above issues, we also present a practical change detection algorithm that uses compressed bag-of-words (BoW) image representation as a scalable solution. The results of experiments conducted on a practical change detection task, "moving object detection (MOD)," using the publicly available Malaga dataset validate the effectiveness of the proposed approach.
no_new_dataset
0.944536
1608.02192
Stephan R Richter
Stephan R. Richter, Vibhav Vineet, Stefan Roth, Vladlen Koltun
Playing for Data: Ground Truth from Computer Games
Accepted to the 14th European Conference on Computer Vision (ECCV 2016)
null
null
null
cs.CV
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Recent progress in computer vision has been driven by high-capacity models trained on large datasets. Unfortunately, creating large datasets with pixel-level labels has been extremely costly due to the amount of human effort required. In this paper, we present an approach to rapidly creating pixel-accurate semantic label maps for images extracted from modern computer games. Although the source code and the internal operation of commercial games are inaccessible, we show that associations between image patches can be reconstructed from the communication between the game and the graphics hardware. This enables rapid propagation of semantic labels within and across images synthesized by the game, with no access to the source code or the content. We validate the presented approach by producing dense pixel-level semantic annotations for 25 thousand images synthesized by a photorealistic open-world computer game. Experiments on semantic segmentation datasets show that using the acquired data to supplement real-world images significantly increases accuracy and that the acquired data enables reducing the amount of hand-labeled real-world data: models trained with game data and just 1/3 of the CamVid training set outperform models trained on the complete CamVid training set.
[ { "version": "v1", "created": "Sun, 7 Aug 2016 08:20:14 GMT" } ]
2016-08-09T00:00:00
[ [ "Richter", "Stephan R.", "" ], [ "Vineet", "Vibhav", "" ], [ "Roth", "Stefan", "" ], [ "Koltun", "Vladlen", "" ] ]
TITLE: Playing for Data: Ground Truth from Computer Games ABSTRACT: Recent progress in computer vision has been driven by high-capacity models trained on large datasets. Unfortunately, creating large datasets with pixel-level labels has been extremely costly due to the amount of human effort required. In this paper, we present an approach to rapidly creating pixel-accurate semantic label maps for images extracted from modern computer games. Although the source code and the internal operation of commercial games are inaccessible, we show that associations between image patches can be reconstructed from the communication between the game and the graphics hardware. This enables rapid propagation of semantic labels within and across images synthesized by the game, with no access to the source code or the content. We validate the presented approach by producing dense pixel-level semantic annotations for 25 thousand images synthesized by a photorealistic open-world computer game. Experiments on semantic segmentation datasets show that using the acquired data to supplement real-world images significantly increases accuracy and that the acquired data enables reducing the amount of hand-labeled real-world data: models trained with game data and just 1/3 of the CamVid training set outperform models trained on the complete CamVid training set.
no_new_dataset
0.950503
1608.02201
Hussein Al-Barazanchi
Hussein A. Al-Barazanchi, Hussam Qassim, Abhishek Verma
Residual CNDS
null
null
null
null
cs.CV
http://creativecommons.org/licenses/by/4.0/
Convolutional Neural networks nowadays are of tremendous importance for any image classification system. One of the most investigated methods to increase the accuracy of CNN is by increasing the depth of CNN. Increasing the depth by stacking more layers also increases the difficulty of training besides making it computationally expensive. Some research found that adding auxiliary forks after intermediate layers increases the accuracy. Specifying which intermediate layer shoud have the fork just addressed recently. Where a simple rule were used to detect the position of intermediate layers that needs the auxiliary supervision fork. This technique known as convolutional neural networks with deep supervision (CNDS). This technique enhanced the accuracy of classification over the straight forward CNN used on the MIT places dataset and ImageNet. In the other side, Residual Learning is another technique emerged recently to ease the training of very deep CNN. Residual Learning framwork changed the learning of layers from unreferenced functions to learning residual function with regard to the layer's input. Residual Learning achieved state of arts results on ImageNet 2015 and COCO competitions. In this paper, we study the effect of adding residual connections to CNDS network. Our experiments results show increasing of accuracy over using CNDS only.
[ { "version": "v1", "created": "Sun, 7 Aug 2016 10:34:02 GMT" } ]
2016-08-09T00:00:00
[ [ "Al-Barazanchi", "Hussein A.", "" ], [ "Qassim", "Hussam", "" ], [ "Verma", "Abhishek", "" ] ]
TITLE: Residual CNDS ABSTRACT: Convolutional Neural networks nowadays are of tremendous importance for any image classification system. One of the most investigated methods to increase the accuracy of CNN is by increasing the depth of CNN. Increasing the depth by stacking more layers also increases the difficulty of training besides making it computationally expensive. Some research found that adding auxiliary forks after intermediate layers increases the accuracy. Specifying which intermediate layer shoud have the fork just addressed recently. Where a simple rule were used to detect the position of intermediate layers that needs the auxiliary supervision fork. This technique known as convolutional neural networks with deep supervision (CNDS). This technique enhanced the accuracy of classification over the straight forward CNN used on the MIT places dataset and ImageNet. In the other side, Residual Learning is another technique emerged recently to ease the training of very deep CNN. Residual Learning framwork changed the learning of layers from unreferenced functions to learning residual function with regard to the layer's input. Residual Learning achieved state of arts results on ImageNet 2015 and COCO competitions. In this paper, we study the effect of adding residual connections to CNDS network. Our experiments results show increasing of accuracy over using CNDS only.
no_new_dataset
0.949763
1608.02236
Shaohua Wan
Shaohua Wan, Zhijun Chen, Tao Zhang, Bo Zhang, Kong-kat Wong
Bootstrapping Face Detection with Hard Negative Examples
null
null
null
null
cs.CV
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Recently significant performance improvement in face detection was made possible by deeply trained convolutional networks. In this report, a novel approach for training state-of-the-art face detector is described. The key is to exploit the idea of hard negative mining and iteratively update the Faster R-CNN based face detector with the hard negatives harvested from a large set of background examples. We demonstrate that our face detector outperforms state-of-the-art detectors on the FDDB dataset, which is the de facto standard for evaluating face detection algorithms.
[ { "version": "v1", "created": "Sun, 7 Aug 2016 16:10:50 GMT" } ]
2016-08-09T00:00:00
[ [ "Wan", "Shaohua", "" ], [ "Chen", "Zhijun", "" ], [ "Zhang", "Tao", "" ], [ "Zhang", "Bo", "" ], [ "Wong", "Kong-kat", "" ] ]
TITLE: Bootstrapping Face Detection with Hard Negative Examples ABSTRACT: Recently significant performance improvement in face detection was made possible by deeply trained convolutional networks. In this report, a novel approach for training state-of-the-art face detector is described. The key is to exploit the idea of hard negative mining and iteratively update the Faster R-CNN based face detector with the hard negatives harvested from a large set of background examples. We demonstrate that our face detector outperforms state-of-the-art detectors on the FDDB dataset, which is the de facto standard for evaluating face detection algorithms.
no_new_dataset
0.955026
1608.02289
Rossano Schifanella
Rossano Schifanella, Paloma de Juan, Joel Tetreault, Liangliang Cao
Detecting Sarcasm in Multimodal Social Platforms
10 pages, 3 figures, final version published in the Proceedings of ACM Multimedia 2016
null
10.1145/2964284.2964321
null
cs.CV cs.CL cs.MM
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Sarcasm is a peculiar form of sentiment expression, where the surface sentiment differs from the implied sentiment. The detection of sarcasm in social media platforms has been applied in the past mainly to textual utterances where lexical indicators (such as interjections and intensifiers), linguistic markers, and contextual information (such as user profiles, or past conversations) were used to detect the sarcastic tone. However, modern social media platforms allow to create multimodal messages where audiovisual content is integrated with the text, making the analysis of a mode in isolation partial. In our work, we first study the relationship between the textual and visual aspects in multimodal posts from three major social media platforms, i.e., Instagram, Tumblr and Twitter, and we run a crowdsourcing task to quantify the extent to which images are perceived as necessary by human annotators. Moreover, we propose two different computational frameworks to detect sarcasm that integrate the textual and visual modalities. The first approach exploits visual semantics trained on an external dataset, and concatenates the semantics features with state-of-the-art textual features. The second method adapts a visual neural network initialized with parameters trained on ImageNet to multimodal sarcastic posts. Results show the positive effect of combining modalities for the detection of sarcasm across platforms and methods.
[ { "version": "v1", "created": "Mon, 8 Aug 2016 00:59:03 GMT" } ]
2016-08-09T00:00:00
[ [ "Schifanella", "Rossano", "" ], [ "de Juan", "Paloma", "" ], [ "Tetreault", "Joel", "" ], [ "Cao", "Liangliang", "" ] ]
TITLE: Detecting Sarcasm in Multimodal Social Platforms ABSTRACT: Sarcasm is a peculiar form of sentiment expression, where the surface sentiment differs from the implied sentiment. The detection of sarcasm in social media platforms has been applied in the past mainly to textual utterances where lexical indicators (such as interjections and intensifiers), linguistic markers, and contextual information (such as user profiles, or past conversations) were used to detect the sarcastic tone. However, modern social media platforms allow to create multimodal messages where audiovisual content is integrated with the text, making the analysis of a mode in isolation partial. In our work, we first study the relationship between the textual and visual aspects in multimodal posts from three major social media platforms, i.e., Instagram, Tumblr and Twitter, and we run a crowdsourcing task to quantify the extent to which images are perceived as necessary by human annotators. Moreover, we propose two different computational frameworks to detect sarcasm that integrate the textual and visual modalities. The first approach exploits visual semantics trained on an external dataset, and concatenates the semantics features with state-of-the-art textual features. The second method adapts a visual neural network initialized with parameters trained on ImageNet to multimodal sarcastic posts. Results show the positive effect of combining modalities for the detection of sarcasm across platforms and methods.
no_new_dataset
0.94474
1608.02307
William Gray Roncal
William Gray Roncal, Colin Lea, Akira Baruah, Gregory D. Hager
SANTIAGO: Spine Association for Neuron Topology Improvement and Graph Optimization
13 pp
null
null
null
cs.CV q-bio.QM
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Developing automated and semi-automated solutions for reconstructing wiring diagrams of the brain from electron micrographs is important for advancing the field of connectomics. While the ultimate goal is to generate a graph of neuron connectivity, most prior automated methods have focused on volume segmentation rather than explicit graph estimation. In these approaches, one of the key, commonly occurring error modes is dendritic shaft-spine fragmentation. We posit that directly addressing this problem of connection identification may provide critical insight into estimating more accurate brain graphs. To this end, we develop a network-centric approach motivated by biological priors image grammars. We build a computer vision pipeline to reconnect fragmented spines to their parent dendrites using both fully-automated and semi-automated approaches. Our experiments show we can learn valid connections despite uncertain segmentation paths. We curate the first known reference dataset for analyzing the performance of various spine-shaft algorithms and demonstrate promising results that recover many previously lost connections. Our automated approach improves the local subgraph score by more than four times and the full graph score by 60 percent. These data, results, and evaluation tools are all available to the broader scientific community. This reframing of the connectomics problem illustrates a semantic, biologically inspired solution to remedy a major problem with neuron tracking.
[ { "version": "v1", "created": "Mon, 8 Aug 2016 03:37:29 GMT" } ]
2016-08-09T00:00:00
[ [ "Roncal", "William Gray", "" ], [ "Lea", "Colin", "" ], [ "Baruah", "Akira", "" ], [ "Hager", "Gregory D.", "" ] ]
TITLE: SANTIAGO: Spine Association for Neuron Topology Improvement and Graph Optimization ABSTRACT: Developing automated and semi-automated solutions for reconstructing wiring diagrams of the brain from electron micrographs is important for advancing the field of connectomics. While the ultimate goal is to generate a graph of neuron connectivity, most prior automated methods have focused on volume segmentation rather than explicit graph estimation. In these approaches, one of the key, commonly occurring error modes is dendritic shaft-spine fragmentation. We posit that directly addressing this problem of connection identification may provide critical insight into estimating more accurate brain graphs. To this end, we develop a network-centric approach motivated by biological priors image grammars. We build a computer vision pipeline to reconnect fragmented spines to their parent dendrites using both fully-automated and semi-automated approaches. Our experiments show we can learn valid connections despite uncertain segmentation paths. We curate the first known reference dataset for analyzing the performance of various spine-shaft algorithms and demonstrate promising results that recover many previously lost connections. Our automated approach improves the local subgraph score by more than four times and the full graph score by 60 percent. These data, results, and evaluation tools are all available to the broader scientific community. This reframing of the connectomics problem illustrates a semantic, biologically inspired solution to remedy a major problem with neuron tracking.
new_dataset
0.957078
1608.02388
Mohamed Ali Mahjoub
Ibtissem Hadj Ali, Mohammed Ali Mahjoub
Database of handwritten Arabic mathematical formulas images
CGIV 2016
null
null
null
cs.CV
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Although publicly available, ground-truthed database have proven useful for training, evaluating, and comparing recognition systems in many domains, the availability of such database for handwritten Arabic mathematical formula recognition in particular, is currently quite poor. In this paper, we present a new public database that contains mathematical expressions available in their off-line handwritten form. Here, we describe the different steps that allowed us to acquire this database, from the creation of the mathematical expression corpora to the transcription of the collected data. Currently, the dataset contains 4 238 off-line handwritten mathematical expressions written by 66 writers and 20 300 handwritten isolated symbol images. The ground truth is also provided for the handwritten expressions as XML files with the number of symbols, and the MATHML structure.
[ { "version": "v1", "created": "Mon, 8 Aug 2016 11:30:35 GMT" } ]
2016-08-09T00:00:00
[ [ "Ali", "Ibtissem Hadj", "" ], [ "Mahjoub", "Mohammed Ali", "" ] ]
TITLE: Database of handwritten Arabic mathematical formulas images ABSTRACT: Although publicly available, ground-truthed database have proven useful for training, evaluating, and comparing recognition systems in many domains, the availability of such database for handwritten Arabic mathematical formula recognition in particular, is currently quite poor. In this paper, we present a new public database that contains mathematical expressions available in their off-line handwritten form. Here, we describe the different steps that allowed us to acquire this database, from the creation of the mathematical expression corpora to the transcription of the collected data. Currently, the dataset contains 4 238 off-line handwritten mathematical expressions written by 66 writers and 20 300 handwritten isolated symbol images. The ground truth is also provided for the handwritten expressions as XML files with the number of symbols, and the MATHML structure.
new_dataset
0.956756
1608.02519
Marina Sokolova
Marina Sokolova, Kanyi Huang, Stan Matwin, Joshua Ramisch, Vera Sazonova, Renee Black, Chris Orwa, Sidney Ochieng, Nanjira Sambuli
Topic Modelling and Event Identification from Twitter Textual Data
17 pages, 2 figures, 5 tables
null
null
null
cs.SI cs.CL
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The tremendous growth of social media content on the Internet has inspired the development of the text analytics to understand and solve real-life problems. Leveraging statistical topic modelling helps researchers and practitioners in better comprehension of textual content as well as provides useful information for further analysis. Statistical topic modelling becomes especially important when we work with large volumes of dynamic text, e.g., Facebook or Twitter datasets. In this study, we summarize the message content of four data sets of Twitter messages relating to challenging social events in Kenya. We use Latent Dirichlet Allocation (LDA) topic modelling to analyze the content. Our study uses two evaluation measures, Normalized Mutual Information (NMI) and topic coherence analysis, to select the best LDA models. The obtained LDA results show that the tool can be effectively used to extract discussion topics and summarize them for further manual analysis
[ { "version": "v1", "created": "Mon, 8 Aug 2016 17:03:03 GMT" } ]
2016-08-09T00:00:00
[ [ "Sokolova", "Marina", "" ], [ "Huang", "Kanyi", "" ], [ "Matwin", "Stan", "" ], [ "Ramisch", "Joshua", "" ], [ "Sazonova", "Vera", "" ], [ "Black", "Renee", "" ], [ "Orwa", "Chris", "" ], [ "Ochieng", "Sidney", "" ], [ "Sambuli", "Nanjira", "" ] ]
TITLE: Topic Modelling and Event Identification from Twitter Textual Data ABSTRACT: The tremendous growth of social media content on the Internet has inspired the development of the text analytics to understand and solve real-life problems. Leveraging statistical topic modelling helps researchers and practitioners in better comprehension of textual content as well as provides useful information for further analysis. Statistical topic modelling becomes especially important when we work with large volumes of dynamic text, e.g., Facebook or Twitter datasets. In this study, we summarize the message content of four data sets of Twitter messages relating to challenging social events in Kenya. We use Latent Dirichlet Allocation (LDA) topic modelling to analyze the content. Our study uses two evaluation measures, Normalized Mutual Information (NMI) and topic coherence analysis, to select the best LDA models. The obtained LDA results show that the tool can be effectively used to extract discussion topics and summarize them for further manual analysis
no_new_dataset
0.944382
1405.1837
Emanuel Lacic
Emanuel Lacic, Dominik Kowald, Lukas Eberhard, Christoph Trattner, Denis Parra, Leandro Marinho
Utilizing Online Social Network and Location-Based Data to Recommend Products and Categories in Online Marketplaces
20 pages book chapter
null
null
null
cs.IR
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Recent research has unveiled the importance of online social networks for improving the quality of recommender systems and encouraged the research community to investigate better ways of exploiting the social information for recommendations. To contribute to this sparse field of research, in this paper we exploit users' interactions along three data sources (marketplace, social network and location-based) to assess their performance in a barely studied domain: recommending products and domains of interests (i.e., product categories) to people in an online marketplace environment. To that end we defined sets of content- and network-based user similarity features for each data source and studied them isolated using an user-based Collaborative Filtering (CF) approach and in combination via a hybrid recommender algorithm, to assess which one provides the best recommendation performance. Interestingly, in our experiments conducted on a rich dataset collected from SecondLife, a popular online virtual world, we found that recommenders relying on user similarity features obtained from the social network data clearly yielded the best results in terms of accuracy in case of predicting products, whereas the features obtained from the marketplace and location-based data sources also obtained very good results in case of predicting categories. This finding indicates that all three types of data sources are important and should be taken into account depending on the level of specialization of the recommendation task.
[ { "version": "v1", "created": "Thu, 8 May 2014 08:43:55 GMT" }, { "version": "v2", "created": "Mon, 8 Sep 2014 07:48:08 GMT" } ]
2016-08-08T00:00:00
[ [ "Lacic", "Emanuel", "" ], [ "Kowald", "Dominik", "" ], [ "Eberhard", "Lukas", "" ], [ "Trattner", "Christoph", "" ], [ "Parra", "Denis", "" ], [ "Marinho", "Leandro", "" ] ]
TITLE: Utilizing Online Social Network and Location-Based Data to Recommend Products and Categories in Online Marketplaces ABSTRACT: Recent research has unveiled the importance of online social networks for improving the quality of recommender systems and encouraged the research community to investigate better ways of exploiting the social information for recommendations. To contribute to this sparse field of research, in this paper we exploit users' interactions along three data sources (marketplace, social network and location-based) to assess their performance in a barely studied domain: recommending products and domains of interests (i.e., product categories) to people in an online marketplace environment. To that end we defined sets of content- and network-based user similarity features for each data source and studied them isolated using an user-based Collaborative Filtering (CF) approach and in combination via a hybrid recommender algorithm, to assess which one provides the best recommendation performance. Interestingly, in our experiments conducted on a rich dataset collected from SecondLife, a popular online virtual world, we found that recommenders relying on user similarity features obtained from the social network data clearly yielded the best results in terms of accuracy in case of predicting products, whereas the features obtained from the marketplace and location-based data sources also obtained very good results in case of predicting categories. This finding indicates that all three types of data sources are important and should be taken into account depending on the level of specialization of the recommendation task.
no_new_dataset
0.952309
1507.04155
Cem Orhan
Cem Orhan and \"Oznur Ta\c{s}tan
ALEVS: Active Learning by Statistical Leverage Sampling
4 pages, presented as contributed talk in ICML 2015 Active Learning Workshop
null
null
null
cs.LG stat.ML
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Active learning aims to obtain a classifier of high accuracy by using fewer label requests in comparison to passive learning by selecting effective queries. Many active learning methods have been developed in the past two decades, which sample queries based on informativeness or representativeness of unlabeled data points. In this work, we explore a novel querying criterion based on statistical leverage scores. The statistical leverage scores of a row in a matrix are the squared row-norms of the matrix containing its (top) left singular vectors and is a measure of influence of the row on the matrix. Leverage scores have been used for detecting high influential points in regression diagnostics and have been recently shown to be useful for data analysis and randomized low-rank matrix approximation algorithms. We explore how sampling data instances with high statistical leverage scores perform in active learning. Our empirical comparison on several binary classification datasets indicate that querying high leverage points is an effective strategy.
[ { "version": "v1", "created": "Wed, 15 Jul 2015 10:31:00 GMT" } ]
2016-08-08T00:00:00
[ [ "Orhan", "Cem", "" ], [ "Taştan", "Öznur", "" ] ]
TITLE: ALEVS: Active Learning by Statistical Leverage Sampling ABSTRACT: Active learning aims to obtain a classifier of high accuracy by using fewer label requests in comparison to passive learning by selecting effective queries. Many active learning methods have been developed in the past two decades, which sample queries based on informativeness or representativeness of unlabeled data points. In this work, we explore a novel querying criterion based on statistical leverage scores. The statistical leverage scores of a row in a matrix are the squared row-norms of the matrix containing its (top) left singular vectors and is a measure of influence of the row on the matrix. Leverage scores have been used for detecting high influential points in regression diagnostics and have been recently shown to be useful for data analysis and randomized low-rank matrix approximation algorithms. We explore how sampling data instances with high statistical leverage scores perform in active learning. Our empirical comparison on several binary classification datasets indicate that querying high leverage points is an effective strategy.
no_new_dataset
0.952175
1601.03892
Massimo Cafaro
Massimo Cafaro, Marco Pulimeno, Italo Epicoco and Giovanni Aloisio
Mining frequent items in the time fading model
To appear in Information Sciences, Elsevier
Information Sciences, Elsevier, 2016, Volume 370-371, pp.221-238
10.1016/j.ins.2016.07.077
null
cs.DS cs.DB
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We present FDCMSS, a new sketch-based algorithm for mining frequent items in data streams. The algorithm cleverly combines key ideas borrowed from forward decay, the Count-Min and the Space Saving algorithms. It works in the time fading model, mining data streams according to the cash register model. We formally prove its correctness and show, through extensive experimental results, that our algorithm outperforms $\lambda$-HCount, a recently developed algorithm, with regard to speed, space used, precision attained and error committed on both synthetic and real datasets.
[ { "version": "v1", "created": "Fri, 15 Jan 2016 12:21:47 GMT" }, { "version": "v2", "created": "Wed, 29 Jun 2016 10:00:22 GMT" }, { "version": "v3", "created": "Tue, 2 Aug 2016 08:24:12 GMT" } ]
2016-08-08T00:00:00
[ [ "Cafaro", "Massimo", "" ], [ "Pulimeno", "Marco", "" ], [ "Epicoco", "Italo", "" ], [ "Aloisio", "Giovanni", "" ] ]
TITLE: Mining frequent items in the time fading model ABSTRACT: We present FDCMSS, a new sketch-based algorithm for mining frequent items in data streams. The algorithm cleverly combines key ideas borrowed from forward decay, the Count-Min and the Space Saving algorithms. It works in the time fading model, mining data streams according to the cash register model. We formally prove its correctness and show, through extensive experimental results, that our algorithm outperforms $\lambda$-HCount, a recently developed algorithm, with regard to speed, space used, precision attained and error committed on both synthetic and real datasets.
no_new_dataset
0.952131
1601.06068
Shashi Narayan
Shashi Narayan, Siva Reddy and Shay B. Cohen
Paraphrase Generation from Latent-Variable PCFGs for Semantic Parsing
10 pages, INLG 2016
null
null
null
cs.CL
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
One of the limitations of semantic parsing approaches to open-domain question answering is the lexicosyntactic gap between natural language questions and knowledge base entries -- there are many ways to ask a question, all with the same answer. In this paper we propose to bridge this gap by generating paraphrases of the input question with the goal that at least one of them will be correctly mapped to a knowledge-base query. We introduce a novel grammar model for paraphrase generation that does not require any sentence-aligned paraphrase corpus. Our key idea is to leverage the flexibility and scalability of latent-variable probabilistic context-free grammars to sample paraphrases. We do an extrinsic evaluation of our paraphrases by plugging them into a semantic parser for Freebase. Our evaluation experiments on the WebQuestions benchmark dataset show that the performance of the semantic parser significantly improves over strong baselines.
[ { "version": "v1", "created": "Fri, 22 Jan 2016 16:50:22 GMT" }, { "version": "v2", "created": "Fri, 5 Aug 2016 12:20:52 GMT" } ]
2016-08-08T00:00:00
[ [ "Narayan", "Shashi", "" ], [ "Reddy", "Siva", "" ], [ "Cohen", "Shay B.", "" ] ]
TITLE: Paraphrase Generation from Latent-Variable PCFGs for Semantic Parsing ABSTRACT: One of the limitations of semantic parsing approaches to open-domain question answering is the lexicosyntactic gap between natural language questions and knowledge base entries -- there are many ways to ask a question, all with the same answer. In this paper we propose to bridge this gap by generating paraphrases of the input question with the goal that at least one of them will be correctly mapped to a knowledge-base query. We introduce a novel grammar model for paraphrase generation that does not require any sentence-aligned paraphrase corpus. Our key idea is to leverage the flexibility and scalability of latent-variable probabilistic context-free grammars to sample paraphrases. We do an extrinsic evaluation of our paraphrases by plugging them into a semantic parser for Freebase. Our evaluation experiments on the WebQuestions benchmark dataset show that the performance of the semantic parser significantly improves over strong baselines.
no_new_dataset
0.933552
1608.01709
Sofiane Abbar
Sofiane Abbar and Tahar Zanouda and Javier Borge-Holthoefer
Robustness and Resilience of cities around the world
8 pages
null
null
null
cs.SI physics.soc-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The concept of city or urban resilience has emerged as one of the key challenges for the next decades. As a consequence, institutions like the United Nations or Rockefeller Foundation have embraced initiatives that increase or improve it. These efforts translate into funded programs both for action on the ground and to develop quantification of resilience, under the for of an index. Ironically, on the academic side there is no clear consensus regarding how resilience should be quantified, or what it exactly refers to in the urban context. Here we attempt to link both extremes providing an example of how to exploit large, publicly available, worldwide urban datasets, to produce objective insight into one of the possible dimensions of urban resilience. We do so via well-established methods in complexity science, such as percolation theory --which has a long tradition at providing valuable information on the vulnerability in complex systems. Our findings uncover large differences among studied cities, both regarding their infrastructural fragility and the imbalances in the distribution of critical services.
[ { "version": "v1", "created": "Thu, 4 Aug 2016 21:58:21 GMT" } ]
2016-08-08T00:00:00
[ [ "Abbar", "Sofiane", "" ], [ "Zanouda", "Tahar", "" ], [ "Borge-Holthoefer", "Javier", "" ] ]
TITLE: Robustness and Resilience of cities around the world ABSTRACT: The concept of city or urban resilience has emerged as one of the key challenges for the next decades. As a consequence, institutions like the United Nations or Rockefeller Foundation have embraced initiatives that increase or improve it. These efforts translate into funded programs both for action on the ground and to develop quantification of resilience, under the for of an index. Ironically, on the academic side there is no clear consensus regarding how resilience should be quantified, or what it exactly refers to in the urban context. Here we attempt to link both extremes providing an example of how to exploit large, publicly available, worldwide urban datasets, to produce objective insight into one of the possible dimensions of urban resilience. We do so via well-established methods in complexity science, such as percolation theory --which has a long tradition at providing valuable information on the vulnerability in complex systems. Our findings uncover large differences among studied cities, both regarding their infrastructural fragility and the imbalances in the distribution of critical services.
no_new_dataset
0.946101
1608.01760
Benjamin Hung Benjamin Hung
Benjamin W.K. Hung and Anura P. Jayasumana
Investigative Simulation: Towards Utilizing Graph Pattern Matching for Investigative Search
8 pages, 6 figures. Paper to appear in the Fosint-SI 2016 conference proceedings in conjunction with the 2016 IEEE/ACM International Conference on Advances in Social Networks Analysis and Mining ASONAM 2016
null
null
null
cs.SI physics.soc-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
This paper proposes the use of graph pattern matching for investigative graph search, which is the process of searching for and prioritizing persons of interest who may exhibit part or all of a pattern of suspicious behaviors or connections. While there are a variety of applications, our principal motivation is to aid law enforcement in the detection of homegrown violent extremists. We introduce investigative simulation, which consists of several necessary extensions to the existing dual simulation graph pattern matching scheme in order to make it appropriate for intelligence analysts and law enforcement officials. Specifically, we impose a categorical label structure on nodes consistent with the nature of indicators in investigations, as well as prune or complete search results to ensure sensibility and usefulness of partial matches to analysts. Lastly, we introduce a natural top-k ranking scheme that can help analysts prioritize investigative efforts. We demonstrate performance of investigative simulation on a real-world large dataset.
[ { "version": "v1", "created": "Fri, 5 Aug 2016 04:51:41 GMT" } ]
2016-08-08T00:00:00
[ [ "Hung", "Benjamin W. K.", "" ], [ "Jayasumana", "Anura P.", "" ] ]
TITLE: Investigative Simulation: Towards Utilizing Graph Pattern Matching for Investigative Search ABSTRACT: This paper proposes the use of graph pattern matching for investigative graph search, which is the process of searching for and prioritizing persons of interest who may exhibit part or all of a pattern of suspicious behaviors or connections. While there are a variety of applications, our principal motivation is to aid law enforcement in the detection of homegrown violent extremists. We introduce investigative simulation, which consists of several necessary extensions to the existing dual simulation graph pattern matching scheme in order to make it appropriate for intelligence analysts and law enforcement officials. Specifically, we impose a categorical label structure on nodes consistent with the nature of indicators in investigations, as well as prune or complete search results to ensure sensibility and usefulness of partial matches to analysts. Lastly, we introduce a natural top-k ranking scheme that can help analysts prioritize investigative efforts. We demonstrate performance of investigative simulation on a real-world large dataset.
no_new_dataset
0.949435
1608.01866
Mustafa Sert
Hilal Ergun and Mustafa Sert
Fusing Deep Convolutional Networks for Large Scale Visual Concept Classification
To appear in The Second IEEE International Conference on Multimedia Big Data (IEEE BigMM 2016)
null
null
null
cs.CV
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Deep learning architectures are showing great promise in various computer vision domains including image classification, object detection, event detection and action recognition. In this study, we investigate various aspects of convolutional neural networks (CNNs) from the big data perspective. We analyze recent studies and different network architectures both in terms of running time and accuracy. We present extensive empirical information along with best practices for big data practitioners. Using these best practices we propose efficient fusion mechanisms both for single and multiple network models. We present state-of-the art results on benchmark datasets while keeping computational costs at a lower level. Another contribution of our paper is that these state-of-the-art results can be reached without using extensive data augmentation techniques.
[ { "version": "v1", "created": "Fri, 5 Aug 2016 12:50:28 GMT" } ]
2016-08-08T00:00:00
[ [ "Ergun", "Hilal", "" ], [ "Sert", "Mustafa", "" ] ]
TITLE: Fusing Deep Convolutional Networks for Large Scale Visual Concept Classification ABSTRACT: Deep learning architectures are showing great promise in various computer vision domains including image classification, object detection, event detection and action recognition. In this study, we investigate various aspects of convolutional neural networks (CNNs) from the big data perspective. We analyze recent studies and different network architectures both in terms of running time and accuracy. We present extensive empirical information along with best practices for big data practitioners. Using these best practices we propose efficient fusion mechanisms both for single and multiple network models. We present state-of-the art results on benchmark datasets while keeping computational costs at a lower level. Another contribution of our paper is that these state-of-the-art results can be reached without using extensive data augmentation techniques.
no_new_dataset
0.952264
1608.01939
Andrea Cuttone
Andrea Cuttone, Sune Lehmann, Marta C. Gonz\'alez
Understanding Predictability and Exploration in Human Mobility
null
null
null
null
cs.CY physics.soc-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Predictive models for human mobility have important applications in many fields such as traffic control, ubiquitous computing and contextual advertisement. The predictive performance of models in literature varies quite broadly, from as high as 93% to as low as under 40%. In this work we investigate which factors influence the accuracy of next-place prediction, using a high-precision location dataset of more than 400 users for periods between 3 months and one year. We show that it is easier to achieve high accuracy when predicting the time-bin location than when predicting the next place. Moreover we demonstrate how the temporal and spatial resolution of the data can have strong influence on the accuracy of prediction. Finally we uncover that the exploration of new locations is an important factor in human mobility, and we measure that on average 20-25% of transitions are to new places, and approx. 70% of locations are visited only once. We discuss how these mechanisms are important factors limiting our ability to predict human mobility.
[ { "version": "v1", "created": "Fri, 5 Aug 2016 17:06:50 GMT" } ]
2016-08-08T00:00:00
[ [ "Cuttone", "Andrea", "" ], [ "Lehmann", "Sune", "" ], [ "González", "Marta C.", "" ] ]
TITLE: Understanding Predictability and Exploration in Human Mobility ABSTRACT: Predictive models for human mobility have important applications in many fields such as traffic control, ubiquitous computing and contextual advertisement. The predictive performance of models in literature varies quite broadly, from as high as 93% to as low as under 40%. In this work we investigate which factors influence the accuracy of next-place prediction, using a high-precision location dataset of more than 400 users for periods between 3 months and one year. We show that it is easier to achieve high accuracy when predicting the time-bin location than when predicting the next place. Moreover we demonstrate how the temporal and spatial resolution of the data can have strong influence on the accuracy of prediction. Finally we uncover that the exploration of new locations is an important factor in human mobility, and we measure that on average 20-25% of transitions are to new places, and approx. 70% of locations are visited only once. We discuss how these mechanisms are important factors limiting our ability to predict human mobility.
new_dataset
0.939748
1608.01961
Mohammad Taher Pilehvar
Mohammad Taher Pilehvar and Nigel Collier
De-Conflated Semantic Representations
EMNLP 2016
null
null
null
cs.CL cs.AI
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
One major deficiency of most semantic representation techniques is that they usually model a word type as a single point in the semantic space, hence conflating all the meanings that the word can have. Addressing this issue by learning distinct representations for individual meanings of words has been the subject of several research studies in the past few years. However, the generated sense representations are either not linked to any sense inventory or are unreliable for infrequent word senses. We propose a technique that tackles these problems by de-conflating the representations of words based on the deep knowledge it derives from a semantic network. Our approach provides multiple advantages in comparison to the past work, including its high coverage and the ability to generate accurate representations even for infrequent word senses. We carry out evaluations on six datasets across two semantic similarity tasks and report state-of-the-art results on most of them.
[ { "version": "v1", "created": "Fri, 5 Aug 2016 18:14:19 GMT" } ]
2016-08-08T00:00:00
[ [ "Pilehvar", "Mohammad Taher", "" ], [ "Collier", "Nigel", "" ] ]
TITLE: De-Conflated Semantic Representations ABSTRACT: One major deficiency of most semantic representation techniques is that they usually model a word type as a single point in the semantic space, hence conflating all the meanings that the word can have. Addressing this issue by learning distinct representations for individual meanings of words has been the subject of several research studies in the past few years. However, the generated sense representations are either not linked to any sense inventory or are unreliable for infrequent word senses. We propose a technique that tackles these problems by de-conflating the representations of words based on the deep knowledge it derives from a semantic network. Our approach provides multiple advantages in comparison to the past work, including its high coverage and the ability to generate accurate representations even for infrequent word senses. We carry out evaluations on six datasets across two semantic similarity tasks and report state-of-the-art results on most of them.
no_new_dataset
0.950227
1608.01987
Peter Krafft
Peter M. Krafft, Julia Zheng, Wei Pan, Nicol\'as Della Penna, Yaniv Altshuler, Erez Shmueli, Joshua B. Tenenbaum, Alex Pentland
Human collective intelligence as distributed Bayesian inference
null
null
null
null
cs.CY cs.AI cs.GT cs.SI physics.soc-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Collective intelligence is believed to underly the remarkable success of human society. The formation of accurate shared beliefs is one of the key components of human collective intelligence. How are accurate shared beliefs formed in groups of fallible individuals? Answering this question requires a multiscale analysis. We must understand both the individual decision mechanisms people use, and the properties and dynamics of those mechanisms in the aggregate. As of yet, mathematical tools for such an approach have been lacking. To address this gap, we introduce a new analytical framework: We propose that groups arrive at accurate shared beliefs via distributed Bayesian inference. Distributed inference occurs through information processing at the individual level, and yields rational belief formation at the group level. We instantiate this framework in a new model of human social decision-making, which we validate using a dataset we collected of over 50,000 users of an online social trading platform where investors mimic each others' trades using real money in foreign exchange and other asset markets. We find that in this setting people use a decision mechanism in which popularity is treated as a prior distribution for which decisions are best to make. This mechanism is boundedly rational at the individual level, but we prove that in the aggregate implements a type of approximate "Thompson sampling"---a well-known and highly effective single-agent Bayesian machine learning algorithm for sequential decision-making. The perspective of distributed Bayesian inference therefore reveals how collective rationality emerges from the boundedly rational decision mechanisms people use.
[ { "version": "v1", "created": "Fri, 5 Aug 2016 19:55:57 GMT" } ]
2016-08-08T00:00:00
[ [ "Krafft", "Peter M.", "" ], [ "Zheng", "Julia", "" ], [ "Pan", "Wei", "" ], [ "Della Penna", "Nicolás", "" ], [ "Altshuler", "Yaniv", "" ], [ "Shmueli", "Erez", "" ], [ "Tenenbaum", "Joshua B.", "" ], [ "Pentland", "Alex", "" ] ]
TITLE: Human collective intelligence as distributed Bayesian inference ABSTRACT: Collective intelligence is believed to underly the remarkable success of human society. The formation of accurate shared beliefs is one of the key components of human collective intelligence. How are accurate shared beliefs formed in groups of fallible individuals? Answering this question requires a multiscale analysis. We must understand both the individual decision mechanisms people use, and the properties and dynamics of those mechanisms in the aggregate. As of yet, mathematical tools for such an approach have been lacking. To address this gap, we introduce a new analytical framework: We propose that groups arrive at accurate shared beliefs via distributed Bayesian inference. Distributed inference occurs through information processing at the individual level, and yields rational belief formation at the group level. We instantiate this framework in a new model of human social decision-making, which we validate using a dataset we collected of over 50,000 users of an online social trading platform where investors mimic each others' trades using real money in foreign exchange and other asset markets. We find that in this setting people use a decision mechanism in which popularity is treated as a prior distribution for which decisions are best to make. This mechanism is boundedly rational at the individual level, but we prove that in the aggregate implements a type of approximate "Thompson sampling"---a well-known and highly effective single-agent Bayesian machine learning algorithm for sequential decision-making. The perspective of distributed Bayesian inference therefore reveals how collective rationality emerges from the boundedly rational decision mechanisms people use.
new_dataset
0.904059
1501.05194
Guillaume Marrelec
Guillaume Marrelec, Arnaud Mess\'e, Pierre Bellec
A Bayesian alternative to mutual information for the hierarchical clustering of dependent random variables
null
G. Marrelec, A. Messe, P. Bellec (2015) A Bayesian alternative to mutual information for the hierarchical clustering of dependent random variables. PLoS ONE 10(9): e0137278
10.1371/journal.pone.0137278
null
stat.ML cs.LG q-bio.QM
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The use of mutual information as a similarity measure in agglomerative hierarchical clustering (AHC) raises an important issue: some correction needs to be applied for the dimensionality of variables. In this work, we formulate the decision of merging dependent multivariate normal variables in an AHC procedure as a Bayesian model comparison. We found that the Bayesian formulation naturally shrinks the empirical covariance matrix towards a matrix set a priori (e.g., the identity), provides an automated stopping rule, and corrects for dimensionality using a term that scales up the measure as a function of the dimensionality of the variables. Also, the resulting log Bayes factor is asymptotically proportional to the plug-in estimate of mutual information, with an additive correction for dimensionality in agreement with the Bayesian information criterion. We investigated the behavior of these Bayesian alternatives (in exact and asymptotic forms) to mutual information on simulated and real data. An encouraging result was first derived on simulations: the hierarchical clustering based on the log Bayes factor outperformed off-the-shelf clustering techniques as well as raw and normalized mutual information in terms of classification accuracy. On a toy example, we found that the Bayesian approaches led to results that were similar to those of mutual information clustering techniques, with the advantage of an automated thresholding. On real functional magnetic resonance imaging (fMRI) datasets measuring brain activity, it identified clusters consistent with the established outcome of standard procedures. On this application, normalized mutual information had a highly atypical behavior, in the sense that it systematically favored very large clusters. These initial experiments suggest that the proposed Bayesian alternatives to mutual information are a useful new tool for hierarchical clustering.
[ { "version": "v1", "created": "Wed, 21 Jan 2015 15:22:13 GMT" }, { "version": "v2", "created": "Mon, 19 Oct 2015 11:31:38 GMT" } ]
2016-08-07T00:00:00
[ [ "Marrelec", "Guillaume", "" ], [ "Messé", "Arnaud", "" ], [ "Bellec", "Pierre", "" ] ]
TITLE: A Bayesian alternative to mutual information for the hierarchical clustering of dependent random variables ABSTRACT: The use of mutual information as a similarity measure in agglomerative hierarchical clustering (AHC) raises an important issue: some correction needs to be applied for the dimensionality of variables. In this work, we formulate the decision of merging dependent multivariate normal variables in an AHC procedure as a Bayesian model comparison. We found that the Bayesian formulation naturally shrinks the empirical covariance matrix towards a matrix set a priori (e.g., the identity), provides an automated stopping rule, and corrects for dimensionality using a term that scales up the measure as a function of the dimensionality of the variables. Also, the resulting log Bayes factor is asymptotically proportional to the plug-in estimate of mutual information, with an additive correction for dimensionality in agreement with the Bayesian information criterion. We investigated the behavior of these Bayesian alternatives (in exact and asymptotic forms) to mutual information on simulated and real data. An encouraging result was first derived on simulations: the hierarchical clustering based on the log Bayes factor outperformed off-the-shelf clustering techniques as well as raw and normalized mutual information in terms of classification accuracy. On a toy example, we found that the Bayesian approaches led to results that were similar to those of mutual information clustering techniques, with the advantage of an automated thresholding. On real functional magnetic resonance imaging (fMRI) datasets measuring brain activity, it identified clusters consistent with the established outcome of standard procedures. On this application, normalized mutual information had a highly atypical behavior, in the sense that it systematically favored very large clusters. These initial experiments suggest that the proposed Bayesian alternatives to mutual information are a useful new tool for hierarchical clustering.
no_new_dataset
0.958187
1509.04513
Vinh Nguyen
Vinh Nguyen, Olivier Bodenreider, Krishnaprasad Thirunarayan, Gang Fu, Evan Bolton, N\'uria Queralt Rosinach, Laura I. Furlong, Michel Dumontier, Amit Sheth
On Reasoning with RDF Statements about Statements using Singleton Property Triples
null
null
null
null
cs.AI cs.DB
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The Singleton Property (SP) approach has been proposed for representing and querying metadata about RDF triples such as provenance, time, location, and evidence. In this approach, one singleton property is created to uniquely represent a relationship in a particular context, and in general, generates a large property hierarchy in the schema. It has become the subject of important questions from Semantic Web practitioners. Can an existing reasoner recognize the singleton property triples? And how? If the singleton property triples describe a data triple, then how can a reasoner infer this data triple from the singleton property triples? Or would the large property hierarchy affect the reasoners in some way? We address these questions in this paper and present our study about the reasoning aspects of the singleton properties. We propose a simple mechanism to enable existing reasoners to recognize the singleton property triples, as well as to infer the data triples described by the singleton property triples. We evaluate the effect of the singleton property triples in the reasoning processes by comparing the performance on RDF datasets with and without singleton properties. Our evaluation uses as benchmark the LUBM datasets and the LUBM-SP datasets derived from LUBM with temporal information added through singleton properties.
[ { "version": "v1", "created": "Tue, 15 Sep 2015 12:10:37 GMT" } ]
2016-08-07T00:00:00
[ [ "Nguyen", "Vinh", "" ], [ "Bodenreider", "Olivier", "" ], [ "Thirunarayan", "Krishnaprasad", "" ], [ "Fu", "Gang", "" ], [ "Bolton", "Evan", "" ], [ "Rosinach", "Núria Queralt", "" ], [ "Furlong", "Laura I.", "" ], [ "Dumontier", "Michel", "" ], [ "Sheth", "Amit", "" ] ]
TITLE: On Reasoning with RDF Statements about Statements using Singleton Property Triples ABSTRACT: The Singleton Property (SP) approach has been proposed for representing and querying metadata about RDF triples such as provenance, time, location, and evidence. In this approach, one singleton property is created to uniquely represent a relationship in a particular context, and in general, generates a large property hierarchy in the schema. It has become the subject of important questions from Semantic Web practitioners. Can an existing reasoner recognize the singleton property triples? And how? If the singleton property triples describe a data triple, then how can a reasoner infer this data triple from the singleton property triples? Or would the large property hierarchy affect the reasoners in some way? We address these questions in this paper and present our study about the reasoning aspects of the singleton properties. We propose a simple mechanism to enable existing reasoners to recognize the singleton property triples, as well as to infer the data triples described by the singleton property triples. We evaluate the effect of the singleton property triples in the reasoning processes by comparing the performance on RDF datasets with and without singleton properties. Our evaluation uses as benchmark the LUBM datasets and the LUBM-SP datasets derived from LUBM with temporal information added through singleton properties.
no_new_dataset
0.9463
1511.00915
Jan Wielemaker
Jan Wielemaker and Torbj\"orn Lager and Fabrizio Riguzzi
SWISH: SWI-Prolog for Sharing
International Workshop on User-Oriented Logic Programming (IULP 2015), co-located with the 31st International Conference on Logic Programming (ICLP 2015), Proceedings of the International Workshop on User-Oriented Logic Programming (IULP 2015), Editors: Stefan Ellmauthaler and Claudia Schulz, pages 99-113, August 2015
null
null
null
cs.PL cs.AI
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Recently, we see a new type of interfaces for programmers based on web technology. For example, JSFiddle, IPython Notebook and R-studio. Web technology enables cloud-based solutions, embedding in tutorial web pages, atractive rendering of results, web-scale cooperative development, etc. This article describes SWISH, a web front-end for Prolog. A public website exposes SWI-Prolog using SWISH, which is used to run small Prolog programs for demonstration, experimentation and education. We connected SWISH to the ClioPatria semantic web toolkit, where it allows for collaborative development of programs and queries related to a dataset as well as performing maintenance tasks on the running server and we embedded SWISH in the Learn Prolog Now! online Prolog book.
[ { "version": "v1", "created": "Tue, 3 Nov 2015 14:16:31 GMT" } ]
2016-08-06T00:00:00
[ [ "Wielemaker", "Jan", "" ], [ "Lager", "Torbjörn", "" ], [ "Riguzzi", "Fabrizio", "" ] ]
TITLE: SWISH: SWI-Prolog for Sharing ABSTRACT: Recently, we see a new type of interfaces for programmers based on web technology. For example, JSFiddle, IPython Notebook and R-studio. Web technology enables cloud-based solutions, embedding in tutorial web pages, atractive rendering of results, web-scale cooperative development, etc. This article describes SWISH, a web front-end for Prolog. A public website exposes SWI-Prolog using SWISH, which is used to run small Prolog programs for demonstration, experimentation and education. We connected SWISH to the ClioPatria semantic web toolkit, where it allows for collaborative development of programs and queries related to a dataset as well as performing maintenance tasks on the running server and we embedded SWISH in the Learn Prolog Now! online Prolog book.
no_new_dataset
0.9462
1511.04834
Arvind Neelakantan
Arvind Neelakantan, Quoc V. Le, Ilya Sutskever
Neural Programmer: Inducing Latent Programs with Gradient Descent
Accepted as a conference paper at ICLR 2015
null
null
null
cs.LG cs.CL stat.ML
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Deep neural networks have achieved impressive supervised classification performance in many tasks including image recognition, speech recognition, and sequence to sequence learning. However, this success has not been translated to applications like question answering that may involve complex arithmetic and logic reasoning. A major limitation of these models is in their inability to learn even simple arithmetic and logic operations. For example, it has been shown that neural networks fail to learn to add two binary numbers reliably. In this work, we propose Neural Programmer, an end-to-end differentiable neural network augmented with a small set of basic arithmetic and logic operations. Neural Programmer can call these augmented operations over several steps, thereby inducing compositional programs that are more complex than the built-in operations. The model learns from a weak supervision signal which is the result of execution of the correct program, hence it does not require expensive annotation of the correct program itself. The decisions of what operations to call, and what data segments to apply to are inferred by Neural Programmer. Such decisions, during training, are done in a differentiable fashion so that the entire network can be trained jointly by gradient descent. We find that training the model is difficult, but it can be greatly improved by adding random noise to the gradient. On a fairly complex synthetic table-comprehension dataset, traditional recurrent networks and attentional models perform poorly while Neural Programmer typically obtains nearly perfect accuracy.
[ { "version": "v1", "created": "Mon, 16 Nov 2015 06:03:58 GMT" }, { "version": "v2", "created": "Tue, 1 Mar 2016 07:00:28 GMT" }, { "version": "v3", "created": "Thu, 4 Aug 2016 18:23:03 GMT" } ]
2016-08-05T00:00:00
[ [ "Neelakantan", "Arvind", "" ], [ "Le", "Quoc V.", "" ], [ "Sutskever", "Ilya", "" ] ]
TITLE: Neural Programmer: Inducing Latent Programs with Gradient Descent ABSTRACT: Deep neural networks have achieved impressive supervised classification performance in many tasks including image recognition, speech recognition, and sequence to sequence learning. However, this success has not been translated to applications like question answering that may involve complex arithmetic and logic reasoning. A major limitation of these models is in their inability to learn even simple arithmetic and logic operations. For example, it has been shown that neural networks fail to learn to add two binary numbers reliably. In this work, we propose Neural Programmer, an end-to-end differentiable neural network augmented with a small set of basic arithmetic and logic operations. Neural Programmer can call these augmented operations over several steps, thereby inducing compositional programs that are more complex than the built-in operations. The model learns from a weak supervision signal which is the result of execution of the correct program, hence it does not require expensive annotation of the correct program itself. The decisions of what operations to call, and what data segments to apply to are inferred by Neural Programmer. Such decisions, during training, are done in a differentiable fashion so that the entire network can be trained jointly by gradient descent. We find that training the model is difficult, but it can be greatly improved by adding random noise to the gradient. On a fairly complex synthetic table-comprehension dataset, traditional recurrent networks and attentional models perform poorly while Neural Programmer typically obtains nearly perfect accuracy.
no_new_dataset
0.941601
1601.05335
Kong Hyeok
Hyeok Kong, Cholyong Jong, Unhyok Ryang
Implementation of Association Rule Mining for Network Intrusion Detection
I have something wrong in submitting the paper
null
null
null
cs.CR cs.DB
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Many modern intrusion detection systems are based on data mining and database-centric architecture, where a number of data mining techniques have been found. Among the most popular techniques, association rule mining is one of the important topics in data mining research. This approach determines interesting relationships between large sets of data items. This technique was initially applied to the so-called market basket analysis, which aims at finding regularities in shopping behaviour of customers of supermarkets. In contrast to dataset for market basket analysis, which takes usually hundreds of attributes, network audit databases face tens of attributes. So the typical Apriori algorithm of association rule mining, which needs so many database scans, can be improved, dealing with such characteristics of transaction database. In this paper we propose an impoved Apriori algorithm, very useful in practice, using scan of network audit database only once by transaction cutting and hashing.
[ { "version": "v1", "created": "Wed, 20 Jan 2016 17:15:44 GMT" }, { "version": "v2", "created": "Thu, 4 Aug 2016 01:03:15 GMT" } ]
2016-08-05T00:00:00
[ [ "Kong", "Hyeok", "" ], [ "Jong", "Cholyong", "" ], [ "Ryang", "Unhyok", "" ] ]
TITLE: Implementation of Association Rule Mining for Network Intrusion Detection ABSTRACT: Many modern intrusion detection systems are based on data mining and database-centric architecture, where a number of data mining techniques have been found. Among the most popular techniques, association rule mining is one of the important topics in data mining research. This approach determines interesting relationships between large sets of data items. This technique was initially applied to the so-called market basket analysis, which aims at finding regularities in shopping behaviour of customers of supermarkets. In contrast to dataset for market basket analysis, which takes usually hundreds of attributes, network audit databases face tens of attributes. So the typical Apriori algorithm of association rule mining, which needs so many database scans, can be improved, dealing with such characteristics of transaction database. In this paper we propose an impoved Apriori algorithm, very useful in practice, using scan of network audit database only once by transaction cutting and hashing.
no_new_dataset
0.946941
1604.02400
P\'adraig Mac Carron
P\'adraig MacCarron, Kimmo Kaski and Robin Dunbar
Calling Dunbar's Numbers
7 pages, 6 figures
Social Networks 47 (2016): 151-155
10.1016/j.socnet.2016.06.003
null
physics.soc-ph cs.SI
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The social brain hypothesis predicts that humans have an average of about 150 relationships at any given time. Within this 150, there are layers of friends of an ego, where the number of friends in a layer increases as the emotional closeness decreases. Here we analyse a mobile phone dataset, firstly, to ascertain whether layers of friends can be identified based on call frequency. We then apply different clustering algorithms to break the call frequency of egos into clusters and compare the number of alters in each cluster with the layer size predicted by the social brain hypothesis. In this dataset we find strong evidence for the existence of a layered structure. The clustering yields results that match well with previous studies for the innermost and outermost layers, but for layers in between we observe large variability.
[ { "version": "v1", "created": "Fri, 8 Apr 2016 16:55:43 GMT" }, { "version": "v2", "created": "Thu, 4 Aug 2016 15:01:25 GMT" } ]
2016-08-05T00:00:00
[ [ "MacCarron", "Pádraig", "" ], [ "Kaski", "Kimmo", "" ], [ "Dunbar", "Robin", "" ] ]
TITLE: Calling Dunbar's Numbers ABSTRACT: The social brain hypothesis predicts that humans have an average of about 150 relationships at any given time. Within this 150, there are layers of friends of an ego, where the number of friends in a layer increases as the emotional closeness decreases. Here we analyse a mobile phone dataset, firstly, to ascertain whether layers of friends can be identified based on call frequency. We then apply different clustering algorithms to break the call frequency of egos into clusters and compare the number of alters in each cluster with the layer size predicted by the social brain hypothesis. In this dataset we find strong evidence for the existence of a layered structure. The clustering yields results that match well with previous studies for the innermost and outermost layers, but for layers in between we observe large variability.
no_new_dataset
0.627209
1604.04038
Kuan-Ting Yu
Kuan-Ting Yu, Maria Bauza, Nima Fazeli, Alberto Rodriguez
More than a Million Ways to Be Pushed: A High-Fidelity Experimental Dataset of Planar Pushing
8 pages, 10 figures
IROS 2016
null
null
cs.RO
http://creativecommons.org/licenses/by-nc-sa/4.0/
Pushing is a motion primitive useful to handle objects that are too large, too heavy, or too cluttered to be grasped. It is at the core of much of robotic manipulation, in particular when physical interaction is involved. It seems reasonable then to wish for robots to understand how pushed objects move. In reality, however, robots often rely on approximations which yield models that are computable, but also restricted and inaccurate. Just how close are those models? How reasonable are the assumptions they are based on? To help answer these questions, and to get a better experimental understanding of pushing, we present a comprehensive and high-fidelity dataset of planar pushing experiments. The dataset contains timestamped poses of a circular pusher and a pushed object, as well as forces at the interaction.We vary the push interaction in 6 dimensions: surface material, shape of the pushed object, contact position, pushing direction, pushing speed, and pushing acceleration. An industrial robot automates the data capturing along precisely controlled position-velocity-acceleration trajectories of the pusher, which give dense samples of positions and forces of uniform quality. We finish the paper by characterizing the variability of friction, and evaluating the most common assumptions and simplifications made by models of frictional pushing in robotics.
[ { "version": "v1", "created": "Thu, 14 Apr 2016 06:08:11 GMT" }, { "version": "v2", "created": "Thu, 4 Aug 2016 02:38:33 GMT" } ]
2016-08-05T00:00:00
[ [ "Yu", "Kuan-Ting", "" ], [ "Bauza", "Maria", "" ], [ "Fazeli", "Nima", "" ], [ "Rodriguez", "Alberto", "" ] ]
TITLE: More than a Million Ways to Be Pushed: A High-Fidelity Experimental Dataset of Planar Pushing ABSTRACT: Pushing is a motion primitive useful to handle objects that are too large, too heavy, or too cluttered to be grasped. It is at the core of much of robotic manipulation, in particular when physical interaction is involved. It seems reasonable then to wish for robots to understand how pushed objects move. In reality, however, robots often rely on approximations which yield models that are computable, but also restricted and inaccurate. Just how close are those models? How reasonable are the assumptions they are based on? To help answer these questions, and to get a better experimental understanding of pushing, we present a comprehensive and high-fidelity dataset of planar pushing experiments. The dataset contains timestamped poses of a circular pusher and a pushed object, as well as forces at the interaction.We vary the push interaction in 6 dimensions: surface material, shape of the pushed object, contact position, pushing direction, pushing speed, and pushing acceleration. An industrial robot automates the data capturing along precisely controlled position-velocity-acceleration trajectories of the pusher, which give dense samples of positions and forces of uniform quality. We finish the paper by characterizing the variability of friction, and evaluating the most common assumptions and simplifications made by models of frictional pushing in robotics.
new_dataset
0.956472
1608.01441
Hao Yang Dr
Hao Yang, Joey Tianyi Zhou and Jianfei Cai
Improving Multi-label Learning with Missing Labels by Structured Semantic Correlations
Accepted in ECCV 2016
null
null
null
cs.CV
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Multi-label learning has attracted significant interests in computer vision recently, finding applications in many vision tasks such as multiple object recognition and automatic image annotation. Associating multiple labels to a complex image is very difficult, not only due to the intricacy of describing the image, but also because of the incompleteness nature of the observed labels. Existing works on the problem either ignore the label-label and instance-instance correlations or just assume these correlations are linear and unstructured. Considering that semantic correlations between images are actually structured, in this paper we propose to incorporate structured semantic correlations to solve the missing label problem of multi-label learning. Specifically, we project images to the semantic space with an effective semantic descriptor. A semantic graph is then constructed on these images to capture the structured correlations between them. We utilize the semantic graph Laplacian as a smooth term in the multi-label learning formulation to incorporate the structured semantic correlations. Experimental results demonstrate the effectiveness of the proposed semantic descriptor and the usefulness of incorporating the structured semantic correlations. We achieve better results than state-of-the-art multi-label learning methods on four benchmark datasets.
[ { "version": "v1", "created": "Thu, 4 Aug 2016 06:58:32 GMT" } ]
2016-08-05T00:00:00
[ [ "Yang", "Hao", "" ], [ "Zhou", "Joey Tianyi", "" ], [ "Cai", "Jianfei", "" ] ]
TITLE: Improving Multi-label Learning with Missing Labels by Structured Semantic Correlations ABSTRACT: Multi-label learning has attracted significant interests in computer vision recently, finding applications in many vision tasks such as multiple object recognition and automatic image annotation. Associating multiple labels to a complex image is very difficult, not only due to the intricacy of describing the image, but also because of the incompleteness nature of the observed labels. Existing works on the problem either ignore the label-label and instance-instance correlations or just assume these correlations are linear and unstructured. Considering that semantic correlations between images are actually structured, in this paper we propose to incorporate structured semantic correlations to solve the missing label problem of multi-label learning. Specifically, we project images to the semantic space with an effective semantic descriptor. A semantic graph is then constructed on these images to capture the structured correlations between them. We utilize the semantic graph Laplacian as a smooth term in the multi-label learning formulation to incorporate the structured semantic correlations. Experimental results demonstrate the effectiveness of the proposed semantic descriptor and the usefulness of incorporating the structured semantic correlations. We achieve better results than state-of-the-art multi-label learning methods on four benchmark datasets.
no_new_dataset
0.947817
1608.01529
Suman Saha
Suman Saha, Gurkirt Singh, Michael Sapienza, Philip H. S. Torr, Fabio Cuzzolin
Deep Learning for Detecting Multiple Space-Time Action Tubes in Videos
Accepted by British Machine Vision Conference 2016
null
null
null
cs.CV
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
In this work, we propose an approach to the spatiotemporal localisation (detection) and classification of multiple concurrent actions within temporally untrimmed videos. Our framework is composed of three stages. In stage 1, appearance and motion detection networks are employed to localise and score actions from colour images and optical flow. In stage 2, the appearance network detections are boosted by combining them with the motion detection scores, in proportion to their respective spatial overlap. In stage 3, sequences of detection boxes most likely to be associated with a single action instance, called action tubes, are constructed by solving two energy maximisation problems via dynamic programming. While in the first pass, action paths spanning the whole video are built by linking detection boxes over time using their class-specific scores and their spatial overlap, in the second pass, temporal trimming is performed by ensuring label consistency for all constituting detection boxes. We demonstrate the performance of our algorithm on the challenging UCF101, J-HMDB-21 and LIRIS-HARL datasets, achieving new state-of-the-art results across the board and significantly increasing detection speed at test time. We achieve a huge leap forward in action detection performance and report a 20% and 11% gain in mAP (mean average precision) on UCF-101 and J-HMDB-21 datasets respectively when compared to the state-of-the-art.
[ { "version": "v1", "created": "Thu, 4 Aug 2016 13:38:38 GMT" } ]
2016-08-05T00:00:00
[ [ "Saha", "Suman", "" ], [ "Singh", "Gurkirt", "" ], [ "Sapienza", "Michael", "" ], [ "Torr", "Philip H. S.", "" ], [ "Cuzzolin", "Fabio", "" ] ]
TITLE: Deep Learning for Detecting Multiple Space-Time Action Tubes in Videos ABSTRACT: In this work, we propose an approach to the spatiotemporal localisation (detection) and classification of multiple concurrent actions within temporally untrimmed videos. Our framework is composed of three stages. In stage 1, appearance and motion detection networks are employed to localise and score actions from colour images and optical flow. In stage 2, the appearance network detections are boosted by combining them with the motion detection scores, in proportion to their respective spatial overlap. In stage 3, sequences of detection boxes most likely to be associated with a single action instance, called action tubes, are constructed by solving two energy maximisation problems via dynamic programming. While in the first pass, action paths spanning the whole video are built by linking detection boxes over time using their class-specific scores and their spatial overlap, in the second pass, temporal trimming is performed by ensuring label consistency for all constituting detection boxes. We demonstrate the performance of our algorithm on the challenging UCF101, J-HMDB-21 and LIRIS-HARL datasets, achieving new state-of-the-art results across the board and significantly increasing detection speed at test time. We achieve a huge leap forward in action detection performance and report a 20% and 11% gain in mAP (mean average precision) on UCF-101 and J-HMDB-21 datasets respectively when compared to the state-of-the-art.
no_new_dataset
0.950549
1608.01561
Paheli Bhattacharya
Paheli Bhattacharya, Pawan Goyal and Sudeshna Sarkar
UsingWord Embeddings for Query Translation for Hindi to English Cross Language Information Retrieval
17th International Conference on Intelligent Text Processing and Computational Linguistics
null
null
null
cs.CL
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Cross-Language Information Retrieval (CLIR) has become an important problem to solve in the recent years due to the growth of content in multiple languages in the Web. One of the standard methods is to use query translation from source to target language. In this paper, we propose an approach based on word embeddings, a method that captures contextual clues for a particular word in the source language and gives those words as translations that occur in a similar context in the target language. Once we obtain the word embeddings of the source and target language pairs, we learn a projection from source to target word embeddings, making use of a dictionary with word translation pairs.We then propose various methods of query translation and aggregation. The advantage of this approach is that it does not require the corpora to be aligned (which is difficult to obtain for resource-scarce languages), a dictionary with word translation pairs is enough to train the word vectors for translation. We experiment with Forum for Information Retrieval and Evaluation (FIRE) 2008 and 2012 datasets for Hindi to English CLIR. The proposed word embedding based approach outperforms the basic dictionary based approach by 70% and when the word embeddings are combined with the dictionary, the hybrid approach beats the baseline dictionary based method by 77%. It outperforms the English monolingual baseline by 15%, when combined with the translations obtained from Google Translate and Dictionary.
[ { "version": "v1", "created": "Thu, 4 Aug 2016 14:44:52 GMT" } ]
2016-08-05T00:00:00
[ [ "Bhattacharya", "Paheli", "" ], [ "Goyal", "Pawan", "" ], [ "Sarkar", "Sudeshna", "" ] ]
TITLE: UsingWord Embeddings for Query Translation for Hindi to English Cross Language Information Retrieval ABSTRACT: Cross-Language Information Retrieval (CLIR) has become an important problem to solve in the recent years due to the growth of content in multiple languages in the Web. One of the standard methods is to use query translation from source to target language. In this paper, we propose an approach based on word embeddings, a method that captures contextual clues for a particular word in the source language and gives those words as translations that occur in a similar context in the target language. Once we obtain the word embeddings of the source and target language pairs, we learn a projection from source to target word embeddings, making use of a dictionary with word translation pairs.We then propose various methods of query translation and aggregation. The advantage of this approach is that it does not require the corpora to be aligned (which is difficult to obtain for resource-scarce languages), a dictionary with word translation pairs is enough to train the word vectors for translation. We experiment with Forum for Information Retrieval and Evaluation (FIRE) 2008 and 2012 datasets for Hindi to English CLIR. The proposed word embedding based approach outperforms the basic dictionary based approach by 70% and when the word embeddings are combined with the dictionary, the hybrid approach beats the baseline dictionary based method by 77%. It outperforms the English monolingual baseline by 15%, when combined with the translations obtained from Google Translate and Dictionary.
no_new_dataset
0.949012
1608.01647
Wei Li
Wei Li and Christina Tsangouri and Farnaz Abtahi and Zhigang Zhu
A Recursive Framework for Expression Recognition: From Web Images to Deep Models to Game Dataset
Submit to Machine Vision Application Journal. arXiv admin note: text overlap with arXiv:1607.02678
null
null
null
cs.CV
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
In this paper, we propose a recursive framework to recognize facial expressions from images in real scenes. Unlike traditional approaches that typically focus on developing and refining algorithms for improving recognition performance on an existing dataset, we integrate three important components in a recursive manner: facial dataset generation, facial expression recognition model building, and interactive interfaces for testing and new data collection. To start with, we first create a candid-images-for-facial-expression (CIFE) dataset. We then apply a convolutional neural network (CNN) to CIFE and build a CNN model for web image expression classification. In order to increase the expression recognition accuracy, we also fine-tune the CNN model and thus obtain a better CNN facial expression recognition model. Based on the fine-tuned CNN model, we design a facial expression game engine and collect a new and more balanced dataset, GaMo. The images of this dataset are collected from the different expressions our game users make when playing the game. Finally, we evaluate the GaMo and CIFE datasets and show that our recursive framework can help build a better facial expression model for dealing with real scene facial expression tasks.
[ { "version": "v1", "created": "Thu, 4 Aug 2016 19:07:08 GMT" } ]
2016-08-05T00:00:00
[ [ "Li", "Wei", "" ], [ "Tsangouri", "Christina", "" ], [ "Abtahi", "Farnaz", "" ], [ "Zhu", "Zhigang", "" ] ]
TITLE: A Recursive Framework for Expression Recognition: From Web Images to Deep Models to Game Dataset ABSTRACT: In this paper, we propose a recursive framework to recognize facial expressions from images in real scenes. Unlike traditional approaches that typically focus on developing and refining algorithms for improving recognition performance on an existing dataset, we integrate three important components in a recursive manner: facial dataset generation, facial expression recognition model building, and interactive interfaces for testing and new data collection. To start with, we first create a candid-images-for-facial-expression (CIFE) dataset. We then apply a convolutional neural network (CNN) to CIFE and build a CNN model for web image expression classification. In order to increase the expression recognition accuracy, we also fine-tune the CNN model and thus obtain a better CNN facial expression recognition model. Based on the fine-tuned CNN model, we design a facial expression game engine and collect a new and more balanced dataset, GaMo. The images of this dataset are collected from the different expressions our game users make when playing the game. Finally, we evaluate the GaMo and CIFE datasets and show that our recursive framework can help build a better facial expression model for dealing with real scene facial expression tasks.
new_dataset
0.965996
1506.02554
Christina Heinze
Christina Heinze, Brian McWilliams, Nicolai Meinshausen
DUAL-LOCO: Distributing Statistical Estimation Using Random Projections
13 pages
Proceedings of the 19th International Conference on Artificial Intelligence and Statistics, 51, 2016, 12 pages
null
null
stat.ML cs.DC cs.LG
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We present DUAL-LOCO, a communication-efficient algorithm for distributed statistical estimation. DUAL-LOCO assumes that the data is distributed according to the features rather than the samples. It requires only a single round of communication where low-dimensional random projections are used to approximate the dependences between features available to different workers. We show that DUAL-LOCO has bounded approximation error which only depends weakly on the number of workers. We compare DUAL-LOCO against a state-of-the-art distributed optimization method on a variety of real world datasets and show that it obtains better speedups while retaining good accuracy.
[ { "version": "v1", "created": "Mon, 8 Jun 2015 15:35:24 GMT" }, { "version": "v2", "created": "Fri, 8 Jan 2016 16:44:27 GMT" } ]
2016-08-04T00:00:00
[ [ "Heinze", "Christina", "" ], [ "McWilliams", "Brian", "" ], [ "Meinshausen", "Nicolai", "" ] ]
TITLE: DUAL-LOCO: Distributing Statistical Estimation Using Random Projections ABSTRACT: We present DUAL-LOCO, a communication-efficient algorithm for distributed statistical estimation. DUAL-LOCO assumes that the data is distributed according to the features rather than the samples. It requires only a single round of communication where low-dimensional random projections are used to approximate the dependences between features available to different workers. We show that DUAL-LOCO has bounded approximation error which only depends weakly on the number of workers. We compare DUAL-LOCO against a state-of-the-art distributed optimization method on a variety of real world datasets and show that it obtains better speedups while retaining good accuracy.
no_new_dataset
0.951051
1603.06568
Haimin Zhang
Haimin Zhang and Min Xu
Modelling Temporal Information Using Discrete Fourier Transform for Recognizing Emotions in User-generated Videos
5 pages. arXiv admin note: substantial text overlap with arXiv:1603.06182
null
null
null
cs.CV
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
With the widespread of user-generated Internet videos, emotion recognition in those videos attracts increasing research efforts. However, most existing works are based on framelevel visual features and/or audio features, which might fail to model the temporal information, e.g. characteristics accumulated along time. In order to capture video temporal information, in this paper, we propose to analyse features in frequency domain transformed by discrete Fourier transform (DFT features). Frame-level features are firstly extract by a pre-trained deep convolutional neural network (CNN). Then, time domain features are transferred and interpolated into DFT features. CNN and DFT features are further encoded and fused for emotion classification. By this way, static image features extracted from a pre-trained deep CNN and temporal information represented by DFT features are jointly considered for video emotion recognition. Experimental results demonstrate that combining DFT features can effectively capture temporal information and therefore improve emotion recognition performance. Our approach has achieved a state-of-the-art performance on the largest video emotion dataset (VideoEmotion-8 dataset), improving accuracy from 51.1% to 62.6%.
[ { "version": "v1", "created": "Sun, 20 Mar 2016 04:46:00 GMT" }, { "version": "v2", "created": "Wed, 3 Aug 2016 00:53:23 GMT" } ]
2016-08-04T00:00:00
[ [ "Zhang", "Haimin", "" ], [ "Xu", "Min", "" ] ]
TITLE: Modelling Temporal Information Using Discrete Fourier Transform for Recognizing Emotions in User-generated Videos ABSTRACT: With the widespread of user-generated Internet videos, emotion recognition in those videos attracts increasing research efforts. However, most existing works are based on framelevel visual features and/or audio features, which might fail to model the temporal information, e.g. characteristics accumulated along time. In order to capture video temporal information, in this paper, we propose to analyse features in frequency domain transformed by discrete Fourier transform (DFT features). Frame-level features are firstly extract by a pre-trained deep convolutional neural network (CNN). Then, time domain features are transferred and interpolated into DFT features. CNN and DFT features are further encoded and fused for emotion classification. By this way, static image features extracted from a pre-trained deep CNN and temporal information represented by DFT features are jointly considered for video emotion recognition. Experimental results demonstrate that combining DFT features can effectively capture temporal information and therefore improve emotion recognition performance. Our approach has achieved a state-of-the-art performance on the largest video emotion dataset (VideoEmotion-8 dataset), improving accuracy from 51.1% to 62.6%.
no_new_dataset
0.948251
1603.07704
Quan Liu
Quan Liu, Hui Jiang, Andrew Evdokimov, Zhen-Hua Ling, Xiaodan Zhu, Si Wei, Yu Hu
Probabilistic Reasoning via Deep Learning: Neural Association Models
Probabilistic reasoning, Winograd Schema Challenge, Deep learning, Neural Networks, Distributed Representation
null
null
null
cs.AI cs.LG cs.NE
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
In this paper, we propose a new deep learning approach, called neural association model (NAM), for probabilistic reasoning in artificial intelligence. We propose to use neural networks to model association between any two events in a domain. Neural networks take one event as input and compute a conditional probability of the other event to model how likely these two events are to be associated. The actual meaning of the conditional probabilities varies between applications and depends on how the models are trained. In this work, as two case studies, we have investigated two NAM structures, namely deep neural networks (DNN) and relation-modulated neural nets (RMNN), on several probabilistic reasoning tasks in AI, including recognizing textual entailment, triple classification in multi-relational knowledge bases and commonsense reasoning. Experimental results on several popular datasets derived from WordNet, FreeBase and ConceptNet have all demonstrated that both DNNs and RMNNs perform equally well and they can significantly outperform the conventional methods available for these reasoning tasks. Moreover, compared with DNNs, RMNNs are superior in knowledge transfer, where a pre-trained model can be quickly extended to an unseen relation after observing only a few training samples. To further prove the effectiveness of the proposed models, in this work, we have applied NAMs to solving challenging Winograd Schema (WS) problems. Experiments conducted on a set of WS problems prove that the proposed models have the potential for commonsense reasoning.
[ { "version": "v1", "created": "Thu, 24 Mar 2016 18:54:18 GMT" }, { "version": "v2", "created": "Wed, 3 Aug 2016 14:31:17 GMT" } ]
2016-08-04T00:00:00
[ [ "Liu", "Quan", "" ], [ "Jiang", "Hui", "" ], [ "Evdokimov", "Andrew", "" ], [ "Ling", "Zhen-Hua", "" ], [ "Zhu", "Xiaodan", "" ], [ "Wei", "Si", "" ], [ "Hu", "Yu", "" ] ]
TITLE: Probabilistic Reasoning via Deep Learning: Neural Association Models ABSTRACT: In this paper, we propose a new deep learning approach, called neural association model (NAM), for probabilistic reasoning in artificial intelligence. We propose to use neural networks to model association between any two events in a domain. Neural networks take one event as input and compute a conditional probability of the other event to model how likely these two events are to be associated. The actual meaning of the conditional probabilities varies between applications and depends on how the models are trained. In this work, as two case studies, we have investigated two NAM structures, namely deep neural networks (DNN) and relation-modulated neural nets (RMNN), on several probabilistic reasoning tasks in AI, including recognizing textual entailment, triple classification in multi-relational knowledge bases and commonsense reasoning. Experimental results on several popular datasets derived from WordNet, FreeBase and ConceptNet have all demonstrated that both DNNs and RMNNs perform equally well and they can significantly outperform the conventional methods available for these reasoning tasks. Moreover, compared with DNNs, RMNNs are superior in knowledge transfer, where a pre-trained model can be quickly extended to an unseen relation after observing only a few training samples. To further prove the effectiveness of the proposed models, in this work, we have applied NAMs to solving challenging Winograd Schema (WS) problems. Experiments conducted on a set of WS problems prove that the proposed models have the potential for commonsense reasoning.
no_new_dataset
0.949106
1606.06472
Linjie Xing
Linjie Xing, Yu Qiao
DeepWriter: A Multi-Stream Deep CNN for Text-independent Writer Identification
This article will be presented at ICFHR 2016
null
null
null
cs.CV
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Text-independent writer identification is challenging due to the huge variation of written contents and the ambiguous written styles of different writers. This paper proposes DeepWriter, a deep multi-stream CNN to learn deep powerful representation for recognizing writers. DeepWriter takes local handwritten patches as input and is trained with softmax classification loss. The main contributions are: 1) we design and optimize multi-stream structure for writer identification task; 2) we introduce data augmentation learning to enhance the performance of DeepWriter; 3) we introduce a patch scanning strategy to handle text image with different lengths. In addition, we find that different languages such as English and Chinese may share common features for writer identification, and joint training can yield better performance. Experimental results on IAM and HWDB datasets show that our models achieve high identification accuracy: 99.01% on 301 writers and 97.03% on 657 writers with one English sentence input, 93.85% on 300 writers with one Chinese character input, which outperform previous methods with a large margin. Moreover, our models obtain accuracy of 98.01% on 301 writers with only 4 English alphabets as input.
[ { "version": "v1", "created": "Tue, 21 Jun 2016 08:25:25 GMT" }, { "version": "v2", "created": "Wed, 3 Aug 2016 03:26:58 GMT" } ]
2016-08-04T00:00:00
[ [ "Xing", "Linjie", "" ], [ "Qiao", "Yu", "" ] ]
TITLE: DeepWriter: A Multi-Stream Deep CNN for Text-independent Writer Identification ABSTRACT: Text-independent writer identification is challenging due to the huge variation of written contents and the ambiguous written styles of different writers. This paper proposes DeepWriter, a deep multi-stream CNN to learn deep powerful representation for recognizing writers. DeepWriter takes local handwritten patches as input and is trained with softmax classification loss. The main contributions are: 1) we design and optimize multi-stream structure for writer identification task; 2) we introduce data augmentation learning to enhance the performance of DeepWriter; 3) we introduce a patch scanning strategy to handle text image with different lengths. In addition, we find that different languages such as English and Chinese may share common features for writer identification, and joint training can yield better performance. Experimental results on IAM and HWDB datasets show that our models achieve high identification accuracy: 99.01% on 301 writers and 97.03% on 657 writers with one English sentence input, 93.85% on 300 writers with one Chinese character input, which outperform previous methods with a large margin. Moreover, our models obtain accuracy of 98.01% on 301 writers with only 4 English alphabets as input.
no_new_dataset
0.950319
1608.00641
Eyasu Mequanint Zemene
Eyasu Zemene, Marcello Pelillo
Interactive Image Segmentation Using Constrained Dominant Sets
Accepted at ECCV 2016
null
null
null
cs.CV
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We propose a new approach to interactive image segmentation based on some properties of a family of quadratic optimization problems related to dominant sets, a well-known graph-theoretic notion of a cluster which generalizes the concept of a maximal clique to edge-weighted graphs. In particular, we show that by properly controlling a regularization parameter which determines the structure and the scale of the underlying problem, we are in a position to extract groups of dominant-set clusters which are constrained to contain user-selected elements. The resulting algorithm can deal naturally with any type of input modality, including scribbles, sloppy contours, and bounding boxes, and is able to robustly handle noisy annotations on the part of the user. Experiments on standard benchmark datasets show the effectiveness of our approach as compared to state-of-the-art algorithms on a variety of natural images under several input conditions.
[ { "version": "v1", "created": "Mon, 1 Aug 2016 23:37:41 GMT" }, { "version": "v2", "created": "Wed, 3 Aug 2016 17:32:04 GMT" } ]
2016-08-04T00:00:00
[ [ "Zemene", "Eyasu", "" ], [ "Pelillo", "Marcello", "" ] ]
TITLE: Interactive Image Segmentation Using Constrained Dominant Sets ABSTRACT: We propose a new approach to interactive image segmentation based on some properties of a family of quadratic optimization problems related to dominant sets, a well-known graph-theoretic notion of a cluster which generalizes the concept of a maximal clique to edge-weighted graphs. In particular, we show that by properly controlling a regularization parameter which determines the structure and the scale of the underlying problem, we are in a position to extract groups of dominant-set clusters which are constrained to contain user-selected elements. The resulting algorithm can deal naturally with any type of input modality, including scribbles, sloppy contours, and bounding boxes, and is able to robustly handle noisy annotations on the part of the user. Experiments on standard benchmark datasets show the effectiveness of our approach as compared to state-of-the-art algorithms on a variety of natural images under several input conditions.
no_new_dataset
0.947039
1608.01024
Iman Abbasnejad
N Dinesh Reddy, Iman Abbasnejad, Sheetal Reddy, Amit Kumar Mondal, Vindhya Devalla
Incremental Real-Time Multibody VSLAM with Trajectory Optimization Using Stereo Camera
Available on IROS
null
null
null
cs.CV
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Real time outdoor navigation in highly dynamic environments is an crucial problem. The recent literature on real time static SLAM don't scale up to dynamic outdoor environments. Most of these methods assume moving objects as outliers or discard the information provided by them. We propose an algorithm to jointly infer the camera trajectory and the moving object trajectory simultaneously. In this paper, we perform a sparse scene flow based motion segmentation using a stereo camera. The segmented objects motion models are used for accurate localization of the camera trajectory as well as the moving objects. We exploit the relationship between moving objects for improving the accuracy of the poses. We formulate the poses as a factor graph incorporating all the constraints. We achieve exact incremental solution by solving a full nonlinear optimization problem in real time. The evaluation is performed on the challenging KITTI dataset with multiple moving cars.Our method outperforms the previous baselines in outdoor navigation.
[ { "version": "v1", "created": "Tue, 2 Aug 2016 23:03:19 GMT" } ]
2016-08-04T00:00:00
[ [ "Reddy", "N Dinesh", "" ], [ "Abbasnejad", "Iman", "" ], [ "Reddy", "Sheetal", "" ], [ "Mondal", "Amit Kumar", "" ], [ "Devalla", "Vindhya", "" ] ]
TITLE: Incremental Real-Time Multibody VSLAM with Trajectory Optimization Using Stereo Camera ABSTRACT: Real time outdoor navigation in highly dynamic environments is an crucial problem. The recent literature on real time static SLAM don't scale up to dynamic outdoor environments. Most of these methods assume moving objects as outliers or discard the information provided by them. We propose an algorithm to jointly infer the camera trajectory and the moving object trajectory simultaneously. In this paper, we perform a sparse scene flow based motion segmentation using a stereo camera. The segmented objects motion models are used for accurate localization of the camera trajectory as well as the moving objects. We exploit the relationship between moving objects for improving the accuracy of the poses. We formulate the poses as a factor graph incorporating all the constraints. We achieve exact incremental solution by solving a full nonlinear optimization problem in real time. The evaluation is performed on the challenging KITTI dataset with multiple moving cars.Our method outperforms the previous baselines in outdoor navigation.
no_new_dataset
0.945197
1608.01026
Victor Fragoso
Victor Fragoso, Walter Scheirer, Joao Hespanha, Matthew Turk
One-Class Slab Support Vector Machine
null
null
null
null
cs.CV
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
This work introduces the one-class slab SVM (OCSSVM), a one-class classifier that aims at improving the performance of the one-class SVM. The proposed strategy reduces the false positive rate and increases the accuracy of detecting instances from novel classes. To this end, it uses two parallel hyperplanes to learn the normal region of the decision scores of the target class. OCSSVM extends one-class SVM since it can scale and learn non-linear decision functions via kernel methods. The experiments on two publicly available datasets show that OCSSVM can consistently outperform the one-class SVM and perform comparable to or better than other state-of-the-art one-class classifiers.
[ { "version": "v1", "created": "Tue, 2 Aug 2016 23:06:35 GMT" } ]
2016-08-04T00:00:00
[ [ "Fragoso", "Victor", "" ], [ "Scheirer", "Walter", "" ], [ "Hespanha", "Joao", "" ], [ "Turk", "Matthew", "" ] ]
TITLE: One-Class Slab Support Vector Machine ABSTRACT: This work introduces the one-class slab SVM (OCSSVM), a one-class classifier that aims at improving the performance of the one-class SVM. The proposed strategy reduces the false positive rate and increases the accuracy of detecting instances from novel classes. To this end, it uses two parallel hyperplanes to learn the normal region of the decision scores of the target class. OCSSVM extends one-class SVM since it can scale and learn non-linear decision functions via kernel methods. The experiments on two publicly available datasets show that OCSSVM can consistently outperform the one-class SVM and perform comparable to or better than other state-of-the-art one-class classifiers.
no_new_dataset
0.948442
1608.01082
Jinghua Wang
Jinghua Wang, Zhenhua Wang, Dacheng Tao, Simon See, Gang Wang
Learning Common and Specific Features for RGB-D Semantic Segmentation with Deconvolutional Networks
ECCV 2016, 16 pages, 3 figures
null
null
null
cs.CV
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
In this paper, we tackle the problem of RGB-D semantic segmentation of indoor images. We take advantage of deconvolutional networks which can predict pixel-wise class labels, and develop a new structure for deconvolution of multiple modalities. We propose a novel feature transformation network to bridge the convolutional networks and deconvolutional networks. In the feature transformation network, we correlate the two modalities by discovering common features between them, as well as characterize each modality by discovering modality specific features. With the common features, we not only closely correlate the two modalities, but also allow them to borrow features from each other to enhance the representation of shared information. With specific features, we capture the visual patterns that are only visible in one modality. The proposed network achieves competitive segmentation accuracy on NYU depth dataset V1 and V2.
[ { "version": "v1", "created": "Wed, 3 Aug 2016 06:05:16 GMT" } ]
2016-08-04T00:00:00
[ [ "Wang", "Jinghua", "" ], [ "Wang", "Zhenhua", "" ], [ "Tao", "Dacheng", "" ], [ "See", "Simon", "" ], [ "Wang", "Gang", "" ] ]
TITLE: Learning Common and Specific Features for RGB-D Semantic Segmentation with Deconvolutional Networks ABSTRACT: In this paper, we tackle the problem of RGB-D semantic segmentation of indoor images. We take advantage of deconvolutional networks which can predict pixel-wise class labels, and develop a new structure for deconvolution of multiple modalities. We propose a novel feature transformation network to bridge the convolutional networks and deconvolutional networks. In the feature transformation network, we correlate the two modalities by discovering common features between them, as well as characterize each modality by discovering modality specific features. With the common features, we not only closely correlate the two modalities, but also allow them to borrow features from each other to enhance the representation of shared information. With specific features, we capture the visual patterns that are only visible in one modality. The proposed network achieves competitive segmentation accuracy on NYU depth dataset V1 and V2.
no_new_dataset
0.952706
1608.01264
Niao He
Niao He, Zaid Harchaoui, Yichen Wang, Le Song
Fast and Simple Optimization for Poisson Likelihood Models
null
null
null
null
cs.LG math.OC stat.ML
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Poisson likelihood models have been prevalently used in imaging, social networks, and time series analysis. We propose fast, simple, theoretically-grounded, and versatile, optimization algorithms for Poisson likelihood modeling. The Poisson log-likelihood is concave but not Lipschitz-continuous. Since almost all gradient-based optimization algorithms rely on Lipschitz-continuity, optimizing Poisson likelihood models with a guarantee of convergence can be challenging, especially for large-scale problems. We present a new perspective allowing to efficiently optimize a wide range of penalized Poisson likelihood objectives. We show that an appropriate saddle point reformulation enjoys a favorable geometry and a smooth structure. Therefore, we can design a new gradient-based optimization algorithm with $O(1/t)$ convergence rate, in contrast to the usual $O(1/\sqrt{t})$ rate of non-smooth minimization alternatives. Furthermore, in order to tackle problems with large samples, we also develop a randomized block-decomposition variant that enjoys the same convergence rate yet more efficient iteration cost. Experimental results on several point process applications including social network estimation and temporal recommendation show that the proposed algorithm and its randomized block variant outperform existing methods both on synthetic and real-world datasets.
[ { "version": "v1", "created": "Wed, 3 Aug 2016 17:33:16 GMT" } ]
2016-08-04T00:00:00
[ [ "He", "Niao", "" ], [ "Harchaoui", "Zaid", "" ], [ "Wang", "Yichen", "" ], [ "Song", "Le", "" ] ]
TITLE: Fast and Simple Optimization for Poisson Likelihood Models ABSTRACT: Poisson likelihood models have been prevalently used in imaging, social networks, and time series analysis. We propose fast, simple, theoretically-grounded, and versatile, optimization algorithms for Poisson likelihood modeling. The Poisson log-likelihood is concave but not Lipschitz-continuous. Since almost all gradient-based optimization algorithms rely on Lipschitz-continuity, optimizing Poisson likelihood models with a guarantee of convergence can be challenging, especially for large-scale problems. We present a new perspective allowing to efficiently optimize a wide range of penalized Poisson likelihood objectives. We show that an appropriate saddle point reformulation enjoys a favorable geometry and a smooth structure. Therefore, we can design a new gradient-based optimization algorithm with $O(1/t)$ convergence rate, in contrast to the usual $O(1/\sqrt{t})$ rate of non-smooth minimization alternatives. Furthermore, in order to tackle problems with large samples, we also develop a randomized block-decomposition variant that enjoys the same convergence rate yet more efficient iteration cost. Experimental results on several point process applications including social network estimation and temporal recommendation show that the proposed algorithm and its randomized block variant outperform existing methods both on synthetic and real-world datasets.
no_new_dataset
0.947137
1608.01281
Navdeep Jaitly
Yuping Luo, Chung-Cheng Chiu, Navdeep Jaitly, Ilya Sutskever
Learning Online Alignments with Continuous Rewards Policy Gradient
null
null
null
null
cs.LG cs.CL
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Sequence-to-sequence models with soft attention had significant success in machine translation, speech recognition, and question answering. Though capable and easy to use, they require that the entirety of the input sequence is available at the beginning of inference, an assumption that is not valid for instantaneous translation and speech recognition. To address this problem, we present a new method for solving sequence-to-sequence problems using hard online alignments instead of soft offline alignments. The online alignments model is able to start producing outputs without the need to first process the entire input sequence. A highly accurate online sequence-to-sequence model is useful because it can be used to build an accurate voice-based instantaneous translator. Our model uses hard binary stochastic decisions to select the timesteps at which outputs will be produced. The model is trained to produce these stochastic decisions using a standard policy gradient method. In our experiments, we show that this model achieves encouraging performance on TIMIT and Wall Street Journal (WSJ) speech recognition datasets.
[ { "version": "v1", "created": "Wed, 3 Aug 2016 18:35:12 GMT" } ]
2016-08-04T00:00:00
[ [ "Luo", "Yuping", "" ], [ "Chiu", "Chung-Cheng", "" ], [ "Jaitly", "Navdeep", "" ], [ "Sutskever", "Ilya", "" ] ]
TITLE: Learning Online Alignments with Continuous Rewards Policy Gradient ABSTRACT: Sequence-to-sequence models with soft attention had significant success in machine translation, speech recognition, and question answering. Though capable and easy to use, they require that the entirety of the input sequence is available at the beginning of inference, an assumption that is not valid for instantaneous translation and speech recognition. To address this problem, we present a new method for solving sequence-to-sequence problems using hard online alignments instead of soft offline alignments. The online alignments model is able to start producing outputs without the need to first process the entire input sequence. A highly accurate online sequence-to-sequence model is useful because it can be used to build an accurate voice-based instantaneous translator. Our model uses hard binary stochastic decisions to select the timesteps at which outputs will be produced. The model is trained to produce these stochastic decisions using a standard policy gradient method. In our experiments, we show that this model achieves encouraging performance on TIMIT and Wall Street Journal (WSJ) speech recognition datasets.
no_new_dataset
0.953665
1608.01298
Peter Wittek
S\'andor Dar\'anyi, Peter Wittek, Konstantinos Konstantinidis, Symeon Papadopoulos, Efstratios Kontopoulos
A Physical Metaphor to Study Semantic Drift
8 pages, 4 figures, to appear in Proceedings of SuCCESS-16, 1st International Workshop on Semantic Change & Evolving Semantics
null
null
null
cs.CL cs.NE stat.ML
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
In accessibility tests for digital preservation, over time we experience drifts of localized and labelled content in statistical models of evolving semantics represented as a vector field. This articulates the need to detect, measure, interpret and model outcomes of knowledge dynamics. To this end we employ a high-performance machine learning algorithm for the training of extremely large emergent self-organizing maps for exploratory data analysis. The working hypothesis we present here is that the dynamics of semantic drifts can be modeled on a relaxed version of Newtonian mechanics called social mechanics. By using term distances as a measure of semantic relatedness vs. their PageRank values indicating social importance and applied as variable `term mass', gravitation as a metaphor to express changes in the semantic content of a vector field lends a new perspective for experimentation. From `term gravitation' over time, one can compute its generating potential whose fluctuations manifest modifications in pairwise term similarity vs. social importance, thereby updating Osgood's semantic differential. The dataset examined is the public catalog metadata of Tate Galleries, London.
[ { "version": "v1", "created": "Wed, 3 Aug 2016 19:34:13 GMT" } ]
2016-08-04T00:00:00
[ [ "Darányi", "Sándor", "" ], [ "Wittek", "Peter", "" ], [ "Konstantinidis", "Konstantinos", "" ], [ "Papadopoulos", "Symeon", "" ], [ "Kontopoulos", "Efstratios", "" ] ]
TITLE: A Physical Metaphor to Study Semantic Drift ABSTRACT: In accessibility tests for digital preservation, over time we experience drifts of localized and labelled content in statistical models of evolving semantics represented as a vector field. This articulates the need to detect, measure, interpret and model outcomes of knowledge dynamics. To this end we employ a high-performance machine learning algorithm for the training of extremely large emergent self-organizing maps for exploratory data analysis. The working hypothesis we present here is that the dynamics of semantic drifts can be modeled on a relaxed version of Newtonian mechanics called social mechanics. By using term distances as a measure of semantic relatedness vs. their PageRank values indicating social importance and applied as variable `term mass', gravitation as a metaphor to express changes in the semantic content of a vector field lends a new perspective for experimentation. From `term gravitation' over time, one can compute its generating potential whose fluctuations manifest modifications in pairwise term similarity vs. social importance, thereby updating Osgood's semantic differential. The dataset examined is the public catalog metadata of Tate Galleries, London.
no_new_dataset
0.952309
1510.02781
Thierry Moreira
Thierry Pinheiro Moreira, Mauricio Lisboa Perez, Rafael de Oliveira Werneck, Eduardo Valle
Where Is My Puppy? Retrieving Lost Dogs by Facial Features
17 pages, 8 figures, 1 table, Multimedia Tools and Applications
null
null
null
cs.CV
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
A pet that goes missing is among many people's worst fears: a moment of distraction is enough for a dog or a cat wandering off from home. Some measures help matching lost animals to their owners; but automated visual recognition is one that - although convenient, highly available, and low-cost - is surprisingly overlooked. In this paper, we inaugurate that promising avenue by pursuing face recognition for dogs. We contrast four ready-to-use human facial recognizers (EigenFaces, FisherFaces, LBPH, and a Sparse method) to two original solutions based upon convolutional neural networks: BARK (inspired in architecture-optimized networks employed for human facial recognition) and WOOF (based upon off-the-shelf OverFeat features). Human facial recognizers perform poorly for dogs (up to 60.5% accuracy), showing that dog facial recognition is not a trivial extension of human facial recognition. The convolutional network solutions work much better, with BARK attaining up to 81.1% accuracy, and WOOF, 89.4%. The tests were conducted in two datasets: Flickr-dog, with 42 dogs of two breeds (pugs and huskies); and Snoopybook, with 18 mongrel dogs.
[ { "version": "v1", "created": "Fri, 9 Oct 2015 19:39:15 GMT" }, { "version": "v2", "created": "Mon, 1 Aug 2016 20:02:15 GMT" } ]
2016-08-03T00:00:00
[ [ "Moreira", "Thierry Pinheiro", "" ], [ "Perez", "Mauricio Lisboa", "" ], [ "Werneck", "Rafael de Oliveira", "" ], [ "Valle", "Eduardo", "" ] ]
TITLE: Where Is My Puppy? Retrieving Lost Dogs by Facial Features ABSTRACT: A pet that goes missing is among many people's worst fears: a moment of distraction is enough for a dog or a cat wandering off from home. Some measures help matching lost animals to their owners; but automated visual recognition is one that - although convenient, highly available, and low-cost - is surprisingly overlooked. In this paper, we inaugurate that promising avenue by pursuing face recognition for dogs. We contrast four ready-to-use human facial recognizers (EigenFaces, FisherFaces, LBPH, and a Sparse method) to two original solutions based upon convolutional neural networks: BARK (inspired in architecture-optimized networks employed for human facial recognition) and WOOF (based upon off-the-shelf OverFeat features). Human facial recognizers perform poorly for dogs (up to 60.5% accuracy), showing that dog facial recognition is not a trivial extension of human facial recognition. The convolutional network solutions work much better, with BARK attaining up to 81.1% accuracy, and WOOF, 89.4%. The tests were conducted in two datasets: Flickr-dog, with 42 dogs of two breeds (pugs and huskies); and Snoopybook, with 18 mongrel dogs.
no_new_dataset
0.940408
1602.05498
Hynek Lavicka
Ji\v{r}\'i Krac\'ik, Hynek Lavi\v{c}ka
Fluctuation analysis of high frequency electric power load in the Czech Republic
sent to Physica A for consideration
null
10.1016/j.physa.2016.06.073
null
physics.soc-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We analyze the electric power load in the Czech Republic (CR) which exhibits a seasonality as well as other oscillations typical for European countries. Moreover, we detect 1/f noise property of electrical power load with extra additional peaks that allows to separate it into a deterministic and stochastic part. We then focus on the analysis of the stochastic part using improved Multi-fractal Detrended Fluctuation Analysis method (MFDFA) to investigate power load datasets with a minute resolution. Extracting the noise part of the signal by using Fourier transform allows us to apply this method to obtain the fluctuation function and to estimate the generalized Hurst exponent together with the correlated Hurst exponent, its improvement for the non-Gaussian datasets. The results exhibit a strong presence of persistent behaviour and the dataset is characterized by a non-Gaussian skewed distribution. There are also indications for the presence of the probability distribution that has heavier tail than the Gaussian distribution.
[ { "version": "v1", "created": "Tue, 16 Feb 2016 15:59:37 GMT" } ]
2016-08-03T00:00:00
[ [ "Kracík", "Jiří", "" ], [ "Lavička", "Hynek", "" ] ]
TITLE: Fluctuation analysis of high frequency electric power load in the Czech Republic ABSTRACT: We analyze the electric power load in the Czech Republic (CR) which exhibits a seasonality as well as other oscillations typical for European countries. Moreover, we detect 1/f noise property of electrical power load with extra additional peaks that allows to separate it into a deterministic and stochastic part. We then focus on the analysis of the stochastic part using improved Multi-fractal Detrended Fluctuation Analysis method (MFDFA) to investigate power load datasets with a minute resolution. Extracting the noise part of the signal by using Fourier transform allows us to apply this method to obtain the fluctuation function and to estimate the generalized Hurst exponent together with the correlated Hurst exponent, its improvement for the non-Gaussian datasets. The results exhibit a strong presence of persistent behaviour and the dataset is characterized by a non-Gaussian skewed distribution. There are also indications for the presence of the probability distribution that has heavier tail than the Gaussian distribution.
no_new_dataset
0.94699
1604.05837
Shyeh Tjing Loi
Shyeh Tjing Loi, Tara Murphy, Iver H. Cairns, Cathryn M. Trott, Natasha Hurley-Walker, Lu Feng, Paul J. Hancock, David L. Kaplan
A new angle for probing field-aligned irregularities with the Murchison Widefield Array
23 pages, 14 figures, accepted for publication in Radio Science
null
10.1002/2015RS005878
null
physics.space-ph astro-ph.IM
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Electron density irregularities in the ionosphere are known to be magnetically anisotropic, preferentially elongated along the lines of force. While many studies of their morphology have been undertaken by topside sounding and whistler measurements, it is only recently that detailed regional-scale reconstructions have become possible, enabled by the advent of widefield radio telescopes. Here we present a new approach for visualising and studying field-aligned irregularities (FAIs), which involves transforming interferometric measurements of TEC gradients onto a magnetic shell tangent plane. This removes the perspective distortion associated with the oblique viewing angle of the irregularities from the ground, facilitating the decomposition of dynamics along and across magnetic field lines. We apply this transformation to the dataset of Loi et al. [2015a], obtained on 15 October 2013 by the Murchison Widefield Array (MWA) radio telescope and displaying prominent FAIs. We study these FAIs in the new reference frame, quantifying field-aligned and field-transverse behaviour, examining time and altitude dependencies, and extending the analysis to FAIs on sub-array scales. We show that the inclination of the plane can be derived solely from the data, and verify that the best-fit value is consistent with the known magnetic inclination. The ability of the model to concentrate the fluctuations along a single spatial direction may find practical application to future calibration strategies for widefield interferometry, by providing a compact representation of FAI-induced distortions.
[ { "version": "v1", "created": "Wed, 20 Apr 2016 06:26:44 GMT" } ]
2016-08-03T00:00:00
[ [ "Loi", "Shyeh Tjing", "" ], [ "Murphy", "Tara", "" ], [ "Cairns", "Iver H.", "" ], [ "Trott", "Cathryn M.", "" ], [ "Hurley-Walker", "Natasha", "" ], [ "Feng", "Lu", "" ], [ "Hancock", "Paul J.", "" ], [ "Kaplan", "David L.", "" ] ]
TITLE: A new angle for probing field-aligned irregularities with the Murchison Widefield Array ABSTRACT: Electron density irregularities in the ionosphere are known to be magnetically anisotropic, preferentially elongated along the lines of force. While many studies of their morphology have been undertaken by topside sounding and whistler measurements, it is only recently that detailed regional-scale reconstructions have become possible, enabled by the advent of widefield radio telescopes. Here we present a new approach for visualising and studying field-aligned irregularities (FAIs), which involves transforming interferometric measurements of TEC gradients onto a magnetic shell tangent plane. This removes the perspective distortion associated with the oblique viewing angle of the irregularities from the ground, facilitating the decomposition of dynamics along and across magnetic field lines. We apply this transformation to the dataset of Loi et al. [2015a], obtained on 15 October 2013 by the Murchison Widefield Array (MWA) radio telescope and displaying prominent FAIs. We study these FAIs in the new reference frame, quantifying field-aligned and field-transverse behaviour, examining time and altitude dependencies, and extending the analysis to FAIs on sub-array scales. We show that the inclination of the plane can be derived solely from the data, and verify that the best-fit value is consistent with the known magnetic inclination. The ability of the model to concentrate the fluctuations along a single spatial direction may find practical application to future calibration strategies for widefield interferometry, by providing a compact representation of FAI-induced distortions.
no_new_dataset
0.947381
1607.03516
Muhammad Ghifary
Muhammad Ghifary and W. Bastiaan Kleijn and Mengjie Zhang and David Balduzzi and Wen Li
Deep Reconstruction-Classification Networks for Unsupervised Domain Adaptation
to appear in European Conference on Computer Vision (ECCV) 2016
null
null
null
cs.CV cs.AI cs.LG stat.ML
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
In this paper, we propose a novel unsupervised domain adaptation algorithm based on deep learning for visual object recognition. Specifically, we design a new model called Deep Reconstruction-Classification Network (DRCN), which jointly learns a shared encoding representation for two tasks: i) supervised classification of labeled source data, and ii) unsupervised reconstruction of unlabeled target data.In this way, the learnt representation not only preserves discriminability, but also encodes useful information from the target domain. Our new DRCN model can be optimized by using backpropagation similarly as the standard neural networks. We evaluate the performance of DRCN on a series of cross-domain object recognition tasks, where DRCN provides a considerable improvement (up to ~8% in accuracy) over the prior state-of-the-art algorithms. Interestingly, we also observe that the reconstruction pipeline of DRCN transforms images from the source domain into images whose appearance resembles the target dataset. This suggests that DRCN's performance is due to constructing a single composite representation that encodes information about both the structure of target images and the classification of source images. Finally, we provide a formal analysis to justify the algorithm's objective in domain adaptation context.
[ { "version": "v1", "created": "Tue, 12 Jul 2016 20:48:58 GMT" }, { "version": "v2", "created": "Mon, 1 Aug 2016 09:58:13 GMT" } ]
2016-08-03T00:00:00
[ [ "Ghifary", "Muhammad", "" ], [ "Kleijn", "W. Bastiaan", "" ], [ "Zhang", "Mengjie", "" ], [ "Balduzzi", "David", "" ], [ "Li", "Wen", "" ] ]
TITLE: Deep Reconstruction-Classification Networks for Unsupervised Domain Adaptation ABSTRACT: In this paper, we propose a novel unsupervised domain adaptation algorithm based on deep learning for visual object recognition. Specifically, we design a new model called Deep Reconstruction-Classification Network (DRCN), which jointly learns a shared encoding representation for two tasks: i) supervised classification of labeled source data, and ii) unsupervised reconstruction of unlabeled target data.In this way, the learnt representation not only preserves discriminability, but also encodes useful information from the target domain. Our new DRCN model can be optimized by using backpropagation similarly as the standard neural networks. We evaluate the performance of DRCN on a series of cross-domain object recognition tasks, where DRCN provides a considerable improvement (up to ~8% in accuracy) over the prior state-of-the-art algorithms. Interestingly, we also observe that the reconstruction pipeline of DRCN transforms images from the source domain into images whose appearance resembles the target dataset. This suggests that DRCN's performance is due to constructing a single composite representation that encodes information about both the structure of target images and the classification of source images. Finally, we provide a formal analysis to justify the algorithm's objective in domain adaptation context.
no_new_dataset
0.948632
1608.00611
Priyadarshini Panda
Priyadarshini Panda, and Kaushik Roy
Attention Tree: Learning Hierarchies of Visual Features for Large-Scale Image Recognition
11 pages, 8 figures, Under review in IEEE Transactions on Neural Networks and Learning systems
null
null
null
cs.CV cs.LG cs.NE
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
One of the key challenges in machine learning is to design a computationally efficient multi-class classifier while maintaining the output accuracy and performance. In this paper, we present a tree-based classifier: Attention Tree (ATree) for large-scale image classification that uses recursive Adaboost training to construct a visual attention hierarchy. The proposed attention model is inspired from the biological 'selective tuning mechanism for cortical visual processing'. We exploit the inherent feature similarity across images in datasets to identify the input variability and use recursive optimization procedure, to determine data partitioning at each node, thereby, learning the attention hierarchy. A set of binary classifiers is organized on top of the learnt hierarchy to minimize the overall test-time complexity. The attention model maximizes the margins for the binary classifiers for optimal decision boundary modelling, leading to better performance at minimal complexity. The proposed framework has been evaluated on both Caltech-256 and SUN datasets and achieves accuracy improvement over state-of-the-art tree-based methods at significantly lower computational cost.
[ { "version": "v1", "created": "Mon, 1 Aug 2016 20:51:29 GMT" } ]
2016-08-03T00:00:00
[ [ "Panda", "Priyadarshini", "" ], [ "Roy", "Kaushik", "" ] ]
TITLE: Attention Tree: Learning Hierarchies of Visual Features for Large-Scale Image Recognition ABSTRACT: One of the key challenges in machine learning is to design a computationally efficient multi-class classifier while maintaining the output accuracy and performance. In this paper, we present a tree-based classifier: Attention Tree (ATree) for large-scale image classification that uses recursive Adaboost training to construct a visual attention hierarchy. The proposed attention model is inspired from the biological 'selective tuning mechanism for cortical visual processing'. We exploit the inherent feature similarity across images in datasets to identify the input variability and use recursive optimization procedure, to determine data partitioning at each node, thereby, learning the attention hierarchy. A set of binary classifiers is organized on top of the learnt hierarchy to minimize the overall test-time complexity. The attention model maximizes the margins for the binary classifiers for optimal decision boundary modelling, leading to better performance at minimal complexity. The proposed framework has been evaluated on both Caltech-256 and SUN datasets and achieves accuracy improvement over state-of-the-art tree-based methods at significantly lower computational cost.
no_new_dataset
0.952175
1608.00667
Hong-Min Chu
Hong-Min Chu, Hsuan-Tien Lin
Can Active Learning Experience Be Transferred?
10 pages, 8 figs, 4 tables, conference
null
null
null
cs.LG cs.AI
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Active learning is an important machine learning problem in reducing the human labeling effort. Current active learning strategies are designed from human knowledge, and are applied on each dataset in an immutable manner. In other words, experience about the usefulness of strategies cannot be updated and transferred to improve active learning on other datasets. This paper initiates a pioneering study on whether active learning experience can be transferred. We first propose a novel active learning model that linearly aggregates existing strategies. The linear weights can then be used to represent the active learning experience. We equip the model with the popular linear upper- confidence-bound (LinUCB) algorithm for contextual bandit to update the weights. Finally, we extend our model to transfer the experience across datasets with the technique of biased regularization. Empirical studies demonstrate that the learned experience not only is competitive with existing strategies on most single datasets, but also can be transferred across datasets to improve the performance on future learning tasks.
[ { "version": "v1", "created": "Tue, 2 Aug 2016 01:30:25 GMT" } ]
2016-08-03T00:00:00
[ [ "Chu", "Hong-Min", "" ], [ "Lin", "Hsuan-Tien", "" ] ]
TITLE: Can Active Learning Experience Be Transferred? ABSTRACT: Active learning is an important machine learning problem in reducing the human labeling effort. Current active learning strategies are designed from human knowledge, and are applied on each dataset in an immutable manner. In other words, experience about the usefulness of strategies cannot be updated and transferred to improve active learning on other datasets. This paper initiates a pioneering study on whether active learning experience can be transferred. We first propose a novel active learning model that linearly aggregates existing strategies. The linear weights can then be used to represent the active learning experience. We equip the model with the popular linear upper- confidence-bound (LinUCB) algorithm for contextual bandit to update the weights. Finally, we extend our model to transfer the experience across datasets with the technique of biased regularization. Empirical studies demonstrate that the learned experience not only is competitive with existing strategies on most single datasets, but also can be transferred across datasets to improve the performance on future learning tasks.
no_new_dataset
0.945751
1608.00753
Nick Schneider
Nick Schneider, Lukas Schneider, Peter Pinggera, Uwe Franke, Marc Pollefeys, Christoph Stiller
Semantically Guided Depth Upsampling
German Conference on Pattern Recognition 2016 (Oral)
null
null
null
cs.CV
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We present a novel method for accurate and efficient up- sampling of sparse depth data, guided by high-resolution imagery. Our approach goes beyond the use of intensity cues only and additionally exploits object boundary cues through structured edge detection and semantic scene labeling for guidance. Both cues are combined within a geodesic distance measure that allows for boundary-preserving depth in- terpolation while utilizing local context. We model the observed scene structure by locally planar elements and formulate the upsampling task as a global energy minimization problem. Our method determines glob- ally consistent solutions and preserves fine details and sharp depth bound- aries. In our experiments on several public datasets at different levels of application, we demonstrate superior performance of our approach over the state-of-the-art, even for very sparse measurements.
[ { "version": "v1", "created": "Tue, 2 Aug 2016 09:44:53 GMT" } ]
2016-08-03T00:00:00
[ [ "Schneider", "Nick", "" ], [ "Schneider", "Lukas", "" ], [ "Pinggera", "Peter", "" ], [ "Franke", "Uwe", "" ], [ "Pollefeys", "Marc", "" ], [ "Stiller", "Christoph", "" ] ]
TITLE: Semantically Guided Depth Upsampling ABSTRACT: We present a novel method for accurate and efficient up- sampling of sparse depth data, guided by high-resolution imagery. Our approach goes beyond the use of intensity cues only and additionally exploits object boundary cues through structured edge detection and semantic scene labeling for guidance. Both cues are combined within a geodesic distance measure that allows for boundary-preserving depth in- terpolation while utilizing local context. We model the observed scene structure by locally planar elements and formulate the upsampling task as a global energy minimization problem. Our method determines glob- ally consistent solutions and preserves fine details and sharp depth bound- aries. In our experiments on several public datasets at different levels of application, we demonstrate superior performance of our approach over the state-of-the-art, even for very sparse measurements.
no_new_dataset
0.954984
1608.00859
Limin Wang
Limin Wang, Yuanjun Xiong, Zhe Wang, Yu Qiao, Dahua Lin, Xiaoou Tang, and Luc Van Gool
Temporal Segment Networks: Towards Good Practices for Deep Action Recognition
Accepted by ECCV 2016. Based on this method, we won the ActivityNet challenge 2016 in untrimmed video classification
null
null
null
cs.CV
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Deep convolutional networks have achieved great success for visual recognition in still images. However, for action recognition in videos, the advantage over traditional methods is not so evident. This paper aims to discover the principles to design effective ConvNet architectures for action recognition in videos and learn these models given limited training samples. Our first contribution is temporal segment network (TSN), a novel framework for video-based action recognition. which is based on the idea of long-range temporal structure modeling. It combines a sparse temporal sampling strategy and video-level supervision to enable efficient and effective learning using the whole action video. The other contribution is our study on a series of good practices in learning ConvNets on video data with the help of temporal segment network. Our approach obtains the state-the-of-art performance on the datasets of HMDB51 ( $ 69.4\% $) and UCF101 ($ 94.2\% $). We also visualize the learned ConvNet models, which qualitatively demonstrates the effectiveness of temporal segment network and the proposed good practices.
[ { "version": "v1", "created": "Tue, 2 Aug 2016 15:06:50 GMT" } ]
2016-08-03T00:00:00
[ [ "Wang", "Limin", "" ], [ "Xiong", "Yuanjun", "" ], [ "Wang", "Zhe", "" ], [ "Qiao", "Yu", "" ], [ "Lin", "Dahua", "" ], [ "Tang", "Xiaoou", "" ], [ "Van Gool", "Luc", "" ] ]
TITLE: Temporal Segment Networks: Towards Good Practices for Deep Action Recognition ABSTRACT: Deep convolutional networks have achieved great success for visual recognition in still images. However, for action recognition in videos, the advantage over traditional methods is not so evident. This paper aims to discover the principles to design effective ConvNet architectures for action recognition in videos and learn these models given limited training samples. Our first contribution is temporal segment network (TSN), a novel framework for video-based action recognition. which is based on the idea of long-range temporal structure modeling. It combines a sparse temporal sampling strategy and video-level supervision to enable efficient and effective learning using the whole action video. The other contribution is our study on a series of good practices in learning ConvNets on video data with the help of temporal segment network. Our approach obtains the state-the-of-art performance on the datasets of HMDB51 ( $ 69.4\% $) and UCF101 ($ 94.2\% $). We also visualize the learned ConvNet models, which qualitatively demonstrates the effectiveness of temporal segment network and the proposed good practices.
no_new_dataset
0.949012
1608.00911
Wen-Sheng Chu
Wen-Sheng Chu, Fernando De la Torre, Jeffrey F. Cohn
Modeling Spatial and Temporal Cues for Multi-label Facial Action Unit Detection
null
null
null
null
cs.CV
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Facial action units (AUs) are essential to decode human facial expressions. Researchers have focused on training AU detectors with a variety of features and classifiers. However, several issues remain. These are spatial representation, temporal modeling, and AU correlation. Unlike most studies that tackle these issues separately, we propose a hybrid network architecture to jointly address them. Specifically, spatial representations are extracted by a Convolutional Neural Network (CNN), which, as analyzed in this paper, is able to reduce person-specific biases caused by hand-crafted features (eg, SIFT and Gabor). To model temporal dependencies, Long Short-Term Memory (LSTMs) are stacked on top of these representations, regardless of the lengths of input videos. The outputs of CNNs and LSTMs are further aggregated into a fusion network to produce per-frame predictions of 12 AUs. Our network naturally addresses the three issues, and leads to superior performance compared to existing methods that consider these issues independently. Extensive experiments were conducted on two large spontaneous datasets, GFT and BP4D, containing more than 400,000 frames coded with 12 AUs. On both datasets, we report significant improvement over a standard multi-label CNN and feature-based state-of-the-art. Finally, we provide visualization of the learned AU models, which, to our best knowledge, reveal how machines see facial AUs for the first time.
[ { "version": "v1", "created": "Tue, 2 Aug 2016 17:37:38 GMT" } ]
2016-08-03T00:00:00
[ [ "Chu", "Wen-Sheng", "" ], [ "De la Torre", "Fernando", "" ], [ "Cohn", "Jeffrey F.", "" ] ]
TITLE: Modeling Spatial and Temporal Cues for Multi-label Facial Action Unit Detection ABSTRACT: Facial action units (AUs) are essential to decode human facial expressions. Researchers have focused on training AU detectors with a variety of features and classifiers. However, several issues remain. These are spatial representation, temporal modeling, and AU correlation. Unlike most studies that tackle these issues separately, we propose a hybrid network architecture to jointly address them. Specifically, spatial representations are extracted by a Convolutional Neural Network (CNN), which, as analyzed in this paper, is able to reduce person-specific biases caused by hand-crafted features (eg, SIFT and Gabor). To model temporal dependencies, Long Short-Term Memory (LSTMs) are stacked on top of these representations, regardless of the lengths of input videos. The outputs of CNNs and LSTMs are further aggregated into a fusion network to produce per-frame predictions of 12 AUs. Our network naturally addresses the three issues, and leads to superior performance compared to existing methods that consider these issues independently. Extensive experiments were conducted on two large spontaneous datasets, GFT and BP4D, containing more than 400,000 frames coded with 12 AUs. On both datasets, we report significant improvement over a standard multi-label CNN and feature-based state-of-the-art. Finally, we provide visualization of the learned AU models, which, to our best knowledge, reveal how machines see facial AUs for the first time.
no_new_dataset
0.944791
1608.00921
Saad Nadeem
Saad Nadeem, Rui Shi, Joseph Marino, Wei Zeng, Xianfeng Gu, and Arie Kaufman
Registration of Volumetric Prostate Scans using Curvature Flow
Technical Report Manuscript prepared: July 2014 --> (Keywords: Shape registration, geometry-based techniques, medical visualization, mathematical foundations for visualization)
null
null
null
cs.GR math.DG
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Radiological imaging of the prostate is becoming more popular among researchers and clinicians in searching for diseases, primarily cancer. Scans might be acquired with different equipment or at different times for prognosis monitoring, with patient movement between scans, resulting in multiple datasets that need to be registered. For these cases, we introduce a method for volumetric registration using curvature flow. Multiple prostate datasets are mapped to canonical solid spheres, which are in turn aligned and registered through the use of identified landmarks on or within the gland. Theoretical proof and experimental results show that our method produces homeomorphisms with feature constraints. We provide thorough validation of our method by registering prostate scans of the same patient in different orientations, from different days and using different modes of MRI. Our method also provides the foundation for a general group-wise registration using a standard reference, defined on the complex plane, for any input. In the present context, this can be used for registering as many scans as needed for a single patient or different patients on the basis of age, weight or even malignant and non-malignant attributes to study the differences in general population. Though we present this technique with a specific application to the prostate, it is generally applicable for volumetric registration problems.
[ { "version": "v1", "created": "Tue, 2 Aug 2016 18:15:34 GMT" } ]
2016-08-03T00:00:00
[ [ "Nadeem", "Saad", "" ], [ "Shi", "Rui", "" ], [ "Marino", "Joseph", "" ], [ "Zeng", "Wei", "" ], [ "Gu", "Xianfeng", "" ], [ "Kaufman", "Arie", "" ] ]
TITLE: Registration of Volumetric Prostate Scans using Curvature Flow ABSTRACT: Radiological imaging of the prostate is becoming more popular among researchers and clinicians in searching for diseases, primarily cancer. Scans might be acquired with different equipment or at different times for prognosis monitoring, with patient movement between scans, resulting in multiple datasets that need to be registered. For these cases, we introduce a method for volumetric registration using curvature flow. Multiple prostate datasets are mapped to canonical solid spheres, which are in turn aligned and registered through the use of identified landmarks on or within the gland. Theoretical proof and experimental results show that our method produces homeomorphisms with feature constraints. We provide thorough validation of our method by registering prostate scans of the same patient in different orientations, from different days and using different modes of MRI. Our method also provides the foundation for a general group-wise registration using a standard reference, defined on the complex plane, for any input. In the present context, this can be used for registering as many scans as needed for a single patient or different patients on the basis of age, weight or even malignant and non-malignant attributes to study the differences in general population. Though we present this technique with a specific application to the prostate, it is generally applicable for volumetric registration problems.
no_new_dataset
0.951278
1503.06465
Joao Carreira
Joao Carreira, Sara Vicente, Lourdes Agapito and Jorge Batista
Lifting Object Detection Datasets into 3D
null
null
null
null
cs.CV
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
While data has certainly taken the center stage in computer vision in recent years, it can still be difficult to obtain in certain scenarios. In particular, acquiring ground truth 3D shapes of objects pictured in 2D images remains a challenging feat and this has hampered progress in recognition-based object reconstruction from a single image. Here we propose to bypass previous solutions such as 3D scanning or manual design, that scale poorly, and instead populate object category detection datasets semi-automatically with dense, per-object 3D reconstructions, bootstrapped from:(i) class labels, (ii) ground truth figure-ground segmentations and (iii) a small set of keypoint annotations. Our proposed algorithm first estimates camera viewpoint using rigid structure-from-motion and then reconstructs object shapes by optimizing over visual hull proposals guided by loose within-class shape similarity assumptions. The visual hull sampling process attempts to intersect an object's projection cone with the cones of minimal subsets of other similar objects among those pictured from certain vantage points. We show that our method is able to produce convincing per-object 3D reconstructions and to accurately estimate cameras viewpoints on one of the most challenging existing object-category detection datasets, PASCAL VOC. We hope that our results will re-stimulate interest on joint object recognition and 3D reconstruction from a single image.
[ { "version": "v1", "created": "Sun, 22 Mar 2015 19:26:57 GMT" }, { "version": "v2", "created": "Sun, 31 Jul 2016 09:49:19 GMT" } ]
2016-08-02T00:00:00
[ [ "Carreira", "Joao", "" ], [ "Vicente", "Sara", "" ], [ "Agapito", "Lourdes", "" ], [ "Batista", "Jorge", "" ] ]
TITLE: Lifting Object Detection Datasets into 3D ABSTRACT: While data has certainly taken the center stage in computer vision in recent years, it can still be difficult to obtain in certain scenarios. In particular, acquiring ground truth 3D shapes of objects pictured in 2D images remains a challenging feat and this has hampered progress in recognition-based object reconstruction from a single image. Here we propose to bypass previous solutions such as 3D scanning or manual design, that scale poorly, and instead populate object category detection datasets semi-automatically with dense, per-object 3D reconstructions, bootstrapped from:(i) class labels, (ii) ground truth figure-ground segmentations and (iii) a small set of keypoint annotations. Our proposed algorithm first estimates camera viewpoint using rigid structure-from-motion and then reconstructs object shapes by optimizing over visual hull proposals guided by loose within-class shape similarity assumptions. The visual hull sampling process attempts to intersect an object's projection cone with the cones of minimal subsets of other similar objects among those pictured from certain vantage points. We show that our method is able to produce convincing per-object 3D reconstructions and to accurately estimate cameras viewpoints on one of the most challenging existing object-category detection datasets, PASCAL VOC. We hope that our results will re-stimulate interest on joint object recognition and 3D reconstruction from a single image.
no_new_dataset
0.944689
1512.04065
Yannis Kalantidis
Yannis Kalantidis, Clayton Mellina, Simon Osindero
Cross-dimensional Weighting for Aggregated Deep Convolutional Features
Accepted for publications at the 4th Workshop on Web-scale Vision and Social Media (VSM), ECCV 2016
null
null
null
cs.CV
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We propose a simple and straightforward way of creating powerful image representations via cross-dimensional weighting and aggregation of deep convolutional neural network layer outputs. We first present a generalized framework that encompasses a broad family of approaches and includes cross-dimensional pooling and weighting steps. We then propose specific non-parametric schemes for both spatial- and channel-wise weighting that boost the effect of highly active spatial responses and at the same time regulate burstiness effects. We experiment on different public datasets for image search and show that our approach outperforms the current state-of-the-art for approaches based on pre-trained networks. We also provide an easy-to-use, open source implementation that reproduces our results.
[ { "version": "v1", "created": "Sun, 13 Dec 2015 15:16:02 GMT" }, { "version": "v2", "created": "Sat, 30 Jul 2016 02:14:18 GMT" } ]
2016-08-02T00:00:00
[ [ "Kalantidis", "Yannis", "" ], [ "Mellina", "Clayton", "" ], [ "Osindero", "Simon", "" ] ]
TITLE: Cross-dimensional Weighting for Aggregated Deep Convolutional Features ABSTRACT: We propose a simple and straightforward way of creating powerful image representations via cross-dimensional weighting and aggregation of deep convolutional neural network layer outputs. We first present a generalized framework that encompasses a broad family of approaches and includes cross-dimensional pooling and weighting steps. We then propose specific non-parametric schemes for both spatial- and channel-wise weighting that boost the effect of highly active spatial responses and at the same time regulate burstiness effects. We experiment on different public datasets for image search and show that our approach outperforms the current state-of-the-art for approaches based on pre-trained networks. We also provide an easy-to-use, open source implementation that reproduces our results.
no_new_dataset
0.950273
1512.09272
Vijay Kumar B G Dr
Vijay Kumar B G, Gustavo Carneiro, Ian Reid
Learning Local Image Descriptors with Deep Siamese and Triplet Convolutional Networks by Minimising Global Loss Functions
IEEE Conference on Computer Vision and Pattern Recognition 2016 (CVPR 2016)
null
null
null
cs.CV
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Recent innovations in training deep convolutional neural network (ConvNet) models have motivated the design of new methods to automatically learn local image descriptors. The latest deep ConvNets proposed for this task consist of a siamese network that is trained by penalising misclassification of pairs of local image patches. Current results from machine learning show that replacing this siamese by a triplet network can improve the classification accuracy in several problems, but this has yet to be demonstrated for local image descriptor learning. Moreover, current siamese and triplet networks have been trained with stochastic gradient descent that computes the gradient from individual pairs or triplets of local image patches, which can make them prone to overfitting. In this paper, we first propose the use of triplet networks for the problem of local image descriptor learning. Furthermore, we also propose the use of a global loss that minimises the overall classification error in the training set, which can improve the generalisation capability of the model. Using the UBC benchmark dataset for comparing local image descriptors, we show that the triplet network produces a more accurate embedding than the siamese network in terms of the UBC dataset errors. Moreover, we also demonstrate that a combination of the triplet and global losses produces the best embedding in the field, using this triplet network. Finally, we also show that the use of the central-surround siamese network trained with the global loss produces the best result of the field on the UBC dataset. Pre-trained models are available online at https://github.com/vijaykbg/deep-patchmatch
[ { "version": "v1", "created": "Thu, 31 Dec 2015 12:36:28 GMT" }, { "version": "v2", "created": "Mon, 1 Aug 2016 06:47:57 GMT" } ]
2016-08-02T00:00:00
[ [ "G", "Vijay Kumar B", "" ], [ "Carneiro", "Gustavo", "" ], [ "Reid", "Ian", "" ] ]
TITLE: Learning Local Image Descriptors with Deep Siamese and Triplet Convolutional Networks by Minimising Global Loss Functions ABSTRACT: Recent innovations in training deep convolutional neural network (ConvNet) models have motivated the design of new methods to automatically learn local image descriptors. The latest deep ConvNets proposed for this task consist of a siamese network that is trained by penalising misclassification of pairs of local image patches. Current results from machine learning show that replacing this siamese by a triplet network can improve the classification accuracy in several problems, but this has yet to be demonstrated for local image descriptor learning. Moreover, current siamese and triplet networks have been trained with stochastic gradient descent that computes the gradient from individual pairs or triplets of local image patches, which can make them prone to overfitting. In this paper, we first propose the use of triplet networks for the problem of local image descriptor learning. Furthermore, we also propose the use of a global loss that minimises the overall classification error in the training set, which can improve the generalisation capability of the model. Using the UBC benchmark dataset for comparing local image descriptors, we show that the triplet network produces a more accurate embedding than the siamese network in terms of the UBC dataset errors. Moreover, we also demonstrate that a combination of the triplet and global losses produces the best embedding in the field, using this triplet network. Finally, we also show that the use of the central-surround siamese network trained with the global loss produces the best result of the field on the UBC dataset. Pre-trained models are available online at https://github.com/vijaykbg/deep-patchmatch
no_new_dataset
0.948822
1603.02844
Chunhua Shen
Bohan Zhuang, Guosheng Lin, Chunhua Shen, Ian Reid
Fast Training of Triplet-based Deep Binary Embedding Networks
Apeparing in Proc. IEEE Conf. Computer Vision and Pattern Recognition 2016. Code is at https://bitbucket.org/jingruixiaozhuang/fast-training-of-triplet-based-deep-binary-embedding-networks
null
null
null
cs.CV
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
In this paper, we aim to learn a mapping (or embedding) from images to a compact binary space in which Hamming distances correspond to a ranking measure for the image retrieval task. We make use of a triplet loss because this has been shown to be most effective for ranking problems. However, training in previous works can be prohibitively expensive due to the fact that optimization is directly performed on the triplet space, where the number of possible triplets for training is cubic in the number of training examples. To address this issue, we propose to formulate high-order binary codes learning as a multi-label classification problem by explicitly separating learning into two interleaved stages. To solve the first stage, we design a large-scale high-order binary codes inference algorithm to reduce the high-order objective to a standard binary quadratic problem such that graph cuts can be used to efficiently infer the binary code which serve as the label of each training datum. In the second stage we propose to map the original image to compact binary codes via carefully designed deep convolutional neural networks (CNNs) and the hashing function fitting can be solved by training binary CNN classifiers. An incremental/interleaved optimization strategy is proffered to ensure that these two steps are interactive with each other during training for better accuracy. We conduct experiments on several benchmark datasets, which demonstrate both improved training time (by as much as two orders of magnitude) as well as producing state-of-the-art hashing for various retrieval tasks.
[ { "version": "v1", "created": "Wed, 9 Mar 2016 11:10:12 GMT" }, { "version": "v2", "created": "Mon, 1 Aug 2016 01:52:57 GMT" } ]
2016-08-02T00:00:00
[ [ "Zhuang", "Bohan", "" ], [ "Lin", "Guosheng", "" ], [ "Shen", "Chunhua", "" ], [ "Reid", "Ian", "" ] ]
TITLE: Fast Training of Triplet-based Deep Binary Embedding Networks ABSTRACT: In this paper, we aim to learn a mapping (or embedding) from images to a compact binary space in which Hamming distances correspond to a ranking measure for the image retrieval task. We make use of a triplet loss because this has been shown to be most effective for ranking problems. However, training in previous works can be prohibitively expensive due to the fact that optimization is directly performed on the triplet space, where the number of possible triplets for training is cubic in the number of training examples. To address this issue, we propose to formulate high-order binary codes learning as a multi-label classification problem by explicitly separating learning into two interleaved stages. To solve the first stage, we design a large-scale high-order binary codes inference algorithm to reduce the high-order objective to a standard binary quadratic problem such that graph cuts can be used to efficiently infer the binary code which serve as the label of each training datum. In the second stage we propose to map the original image to compact binary codes via carefully designed deep convolutional neural networks (CNNs) and the hashing function fitting can be solved by training binary CNN classifiers. An incremental/interleaved optimization strategy is proffered to ensure that these two steps are interactive with each other during training for better accuracy. We conduct experiments on several benchmark datasets, which demonstrate both improved training time (by as much as two orders of magnitude) as well as producing state-of-the-art hashing for various retrieval tasks.
no_new_dataset
0.947381
1604.06480
Yannis Kalantidis
Yannis Kalantidis, Lyndon Kennedy, Huy Nguyen, Clayton Mellina, David A. Shamma
LOH and behold: Web-scale visual search, recommendation and clustering using Locally Optimized Hashing
Accepted for publication at the 4th Workshop on Web-scale Vision and Social Media (VSM), ECCV 2016
null
null
null
cs.CV cs.IR cs.MM
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We propose a novel hashing-based matching scheme, called Locally Optimized Hashing (LOH), based on a state-of-the-art quantization algorithm that can be used for efficient, large-scale search, recommendation, clustering, and deduplication. We show that matching with LOH only requires set intersections and summations to compute and so is easily implemented in generic distributed computing systems. We further show application of LOH to: a) large-scale search tasks where performance is on par with other state-of-the-art hashing approaches; b) large-scale recommendation where queries consisting of thousands of images can be used to generate accurate recommendations from collections of hundreds of millions of images; and c) efficient clustering with a graph-based algorithm that can be scaled to massive collections in a distributed environment or can be used for deduplication for small collections, like search results, performing better than traditional hashing approaches while only requiring a few milliseconds to run. In this paper we experiment on datasets of up to 100 million images, but in practice our system can scale to larger collections and can be used for other types of data that have a vector representation in a Euclidean space.
[ { "version": "v1", "created": "Thu, 21 Apr 2016 20:23:55 GMT" }, { "version": "v2", "created": "Sat, 30 Jul 2016 02:34:52 GMT" } ]
2016-08-02T00:00:00
[ [ "Kalantidis", "Yannis", "" ], [ "Kennedy", "Lyndon", "" ], [ "Nguyen", "Huy", "" ], [ "Mellina", "Clayton", "" ], [ "Shamma", "David A.", "" ] ]
TITLE: LOH and behold: Web-scale visual search, recommendation and clustering using Locally Optimized Hashing ABSTRACT: We propose a novel hashing-based matching scheme, called Locally Optimized Hashing (LOH), based on a state-of-the-art quantization algorithm that can be used for efficient, large-scale search, recommendation, clustering, and deduplication. We show that matching with LOH only requires set intersections and summations to compute and so is easily implemented in generic distributed computing systems. We further show application of LOH to: a) large-scale search tasks where performance is on par with other state-of-the-art hashing approaches; b) large-scale recommendation where queries consisting of thousands of images can be used to generate accurate recommendations from collections of hundreds of millions of images; and c) efficient clustering with a graph-based algorithm that can be scaled to massive collections in a distributed environment or can be used for deduplication for small collections, like search results, performing better than traditional hashing approaches while only requiring a few milliseconds to run. In this paper we experiment on datasets of up to 100 million images, but in practice our system can scale to larger collections and can be used for other types of data that have a vector representation in a Euclidean space.
no_new_dataset
0.950641
1607.04564
Yi Zhou
Yi Zhou, Li Liu, Ling Shao and Matt Mellor
DAVE: A Unified Framework for Fast Vehicle Detection and Annotation
This paper has been accepted by ECCV 2016
null
null
null
cs.CV
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Vehicle detection and annotation for streaming video data with complex scenes is an interesting but challenging task for urban traffic surveillance. In this paper, we present a fast framework of Detection and Annotation for Vehicles (DAVE), which effectively combines vehicle detection and attributes annotation. DAVE consists of two convolutional neural networks (CNNs): a fast vehicle proposal network (FVPN) for vehicle-like objects extraction and an attributes learning network (ALN) aiming to verify each proposal and infer each vehicle's pose, color and type simultaneously. These two nets are jointly optimized so that abundant latent knowledge learned from the ALN can be exploited to guide FVPN training. Once the system is trained, it can achieve efficient vehicle detection and annotation for real-world traffic surveillance data. We evaluate DAVE on a new self-collected UTS dataset and the public PASCAL VOC2007 car and LISA 2010 datasets, with consistent improvements over existing algorithms.
[ { "version": "v1", "created": "Fri, 15 Jul 2016 15:58:16 GMT" }, { "version": "v2", "created": "Mon, 18 Jul 2016 10:55:12 GMT" }, { "version": "v3", "created": "Mon, 1 Aug 2016 08:52:55 GMT" } ]
2016-08-02T00:00:00
[ [ "Zhou", "Yi", "" ], [ "Liu", "Li", "" ], [ "Shao", "Ling", "" ], [ "Mellor", "Matt", "" ] ]
TITLE: DAVE: A Unified Framework for Fast Vehicle Detection and Annotation ABSTRACT: Vehicle detection and annotation for streaming video data with complex scenes is an interesting but challenging task for urban traffic surveillance. In this paper, we present a fast framework of Detection and Annotation for Vehicles (DAVE), which effectively combines vehicle detection and attributes annotation. DAVE consists of two convolutional neural networks (CNNs): a fast vehicle proposal network (FVPN) for vehicle-like objects extraction and an attributes learning network (ALN) aiming to verify each proposal and infer each vehicle's pose, color and type simultaneously. These two nets are jointly optimized so that abundant latent knowledge learned from the ALN can be exploited to guide FVPN training. Once the system is trained, it can achieve efficient vehicle detection and annotation for real-world traffic surveillance data. We evaluate DAVE on a new self-collected UTS dataset and the public PASCAL VOC2007 car and LISA 2010 datasets, with consistent improvements over existing algorithms.
new_dataset
0.962036
1608.00027
Rhiannon Rose
Rhiannon V. Rose, Daniel J. Lizotte
gLOP: the global and Local Penalty for Capturing Predictive Heterogeneity
Presented at 2016 Machine Learning and Healthcare Conference (MLHC 2016), Los Angeles, CA
null
null
null
stat.ML cs.LG
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
When faced with a supervised learning problem, we hope to have rich enough data to build a model that predicts future instances well. However, in practice, problems can exhibit predictive heterogeneity: most instances might be relatively easy to predict, while others might be predictive outliers for which a model trained on the entire dataset does not perform well. Identifying these can help focus future data collection. We present gLOP, the global and Local Penalty, a framework for capturing predictive heterogeneity and identifying predictive outliers. gLOP is based on penalized regression for multitask learning, which improves learning by leveraging training signal information from related tasks. We give two optimization algorithms for gLOP, one space-efficient, and another giving the full regularization path. We also characterize uniqueness in terms of the data and tuning parameters, and present empirical results on synthetic data and on two health research problems.
[ { "version": "v1", "created": "Fri, 29 Jul 2016 20:57:06 GMT" } ]
2016-08-02T00:00:00
[ [ "Rose", "Rhiannon V.", "" ], [ "Lizotte", "Daniel J.", "" ] ]
TITLE: gLOP: the global and Local Penalty for Capturing Predictive Heterogeneity ABSTRACT: When faced with a supervised learning problem, we hope to have rich enough data to build a model that predicts future instances well. However, in practice, problems can exhibit predictive heterogeneity: most instances might be relatively easy to predict, while others might be predictive outliers for which a model trained on the entire dataset does not perform well. Identifying these can help focus future data collection. We present gLOP, the global and Local Penalty, a framework for capturing predictive heterogeneity and identifying predictive outliers. gLOP is based on penalized regression for multitask learning, which improves learning by leveraging training signal information from related tasks. We give two optimization algorithms for gLOP, one space-efficient, and another giving the full regularization path. We also characterize uniqueness in terms of the data and tuning parameters, and present empirical results on synthetic data and on two health research problems.
no_new_dataset
0.949623
1608.00104
Chenguang Wang
Chenguang Wang, Yangqiu Song, Dan Roth, Ming Zhang, Jiawei Han
World Knowledge as Indirect Supervision for Document Clustering
33 pages, 53 figures, ACM TKDD 2016
null
null
null
cs.LG cs.CL cs.IR
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
One of the key obstacles in making learning protocols realistic in applications is the need to supervise them, a costly process that often requires hiring domain experts. We consider the framework to use the world knowledge as indirect supervision. World knowledge is general-purpose knowledge, which is not designed for any specific domain. Then the key challenges are how to adapt the world knowledge to domains and how to represent it for learning. In this paper, we provide an example of using world knowledge for domain dependent document clustering. We provide three ways to specify the world knowledge to domains by resolving the ambiguity of the entities and their types, and represent the data with world knowledge as a heterogeneous information network. Then we propose a clustering algorithm that can cluster multiple types and incorporate the sub-type information as constraints. In the experiments, we use two existing knowledge bases as our sources of world knowledge. One is Freebase, which is collaboratively collected knowledge about entities and their organizations. The other is YAGO2, a knowledge base automatically extracted from Wikipedia and maps knowledge to the linguistic knowledge base, WordNet. Experimental results on two text benchmark datasets (20newsgroups and RCV1) show that incorporating world knowledge as indirect supervision can significantly outperform the state-of-the-art clustering algorithms as well as clustering algorithms enhanced with world knowledge features.
[ { "version": "v1", "created": "Sat, 30 Jul 2016 11:53:04 GMT" } ]
2016-08-02T00:00:00
[ [ "Wang", "Chenguang", "" ], [ "Song", "Yangqiu", "" ], [ "Roth", "Dan", "" ], [ "Zhang", "Ming", "" ], [ "Han", "Jiawei", "" ] ]
TITLE: World Knowledge as Indirect Supervision for Document Clustering ABSTRACT: One of the key obstacles in making learning protocols realistic in applications is the need to supervise them, a costly process that often requires hiring domain experts. We consider the framework to use the world knowledge as indirect supervision. World knowledge is general-purpose knowledge, which is not designed for any specific domain. Then the key challenges are how to adapt the world knowledge to domains and how to represent it for learning. In this paper, we provide an example of using world knowledge for domain dependent document clustering. We provide three ways to specify the world knowledge to domains by resolving the ambiguity of the entities and their types, and represent the data with world knowledge as a heterogeneous information network. Then we propose a clustering algorithm that can cluster multiple types and incorporate the sub-type information as constraints. In the experiments, we use two existing knowledge bases as our sources of world knowledge. One is Freebase, which is collaboratively collected knowledge about entities and their organizations. The other is YAGO2, a knowledge base automatically extracted from Wikipedia and maps knowledge to the linguistic knowledge base, WordNet. Experimental results on two text benchmark datasets (20newsgroups and RCV1) show that incorporating world knowledge as indirect supervision can significantly outperform the state-of-the-art clustering algorithms as well as clustering algorithms enhanced with world knowledge features.
no_new_dataset
0.948251
1608.00148
Bilal Ahmed
Bilal Ahmed and Thomas Thesen and Karen E. Blackmon and Ruben Kuzniecky and Orrin Devinsky and Jennifer G. Dy and Carla E. Brodley
Multi-task Learning with Weak Class Labels: Leveraging iEEG to Detect Cortical Lesions in Cryptogenic Epilepsy
Presented at 2016 Machine Learning and Healthcare Conference (MLHC 2016), Los Angeles, CA
null
null
null
cs.CV
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Multi-task learning (MTL) is useful for domains in which data originates from multiple sources that are individually under-sampled. MTL methods are able to learn classification models that have higher performance as compared to learning a single model by aggregating all the data together or learning a separate model for each data source. The performance of these methods relies on label accuracy. We address the problem of simultaneously learning multiple classifiers in the MTL framework when the training data has imprecise labels. We assume that there is an additional source of information that provides a score for each instance which reflects the certainty about its label. Modeling this score as being generated by an underlying ranking function, we augment the MTL framework with an added layer of supervision. This results in new MTL methods that are able to learn accurate classifiers while preserving the domain structure provided through the rank information. We apply these methods to the task of detecting abnormal cortical regions in the MRIs of patients suffering from focal epilepsy whose MRI were read as normal by expert neuroradiologists. In addition to the noisy labels provided by the results of surgical resection, we employ the results of an invasive intracranial-EEG exam as an additional source of label information. Our proposed methods are able to successfully detect abnormal regions for all patients in our dataset and achieve a higher performance as compared to baseline methods.
[ { "version": "v1", "created": "Sat, 30 Jul 2016 17:04:47 GMT" } ]
2016-08-02T00:00:00
[ [ "Ahmed", "Bilal", "" ], [ "Thesen", "Thomas", "" ], [ "Blackmon", "Karen E.", "" ], [ "Kuzniecky", "Ruben", "" ], [ "Devinsky", "Orrin", "" ], [ "Dy", "Jennifer G.", "" ], [ "Brodley", "Carla E.", "" ] ]
TITLE: Multi-task Learning with Weak Class Labels: Leveraging iEEG to Detect Cortical Lesions in Cryptogenic Epilepsy ABSTRACT: Multi-task learning (MTL) is useful for domains in which data originates from multiple sources that are individually under-sampled. MTL methods are able to learn classification models that have higher performance as compared to learning a single model by aggregating all the data together or learning a separate model for each data source. The performance of these methods relies on label accuracy. We address the problem of simultaneously learning multiple classifiers in the MTL framework when the training data has imprecise labels. We assume that there is an additional source of information that provides a score for each instance which reflects the certainty about its label. Modeling this score as being generated by an underlying ranking function, we augment the MTL framework with an added layer of supervision. This results in new MTL methods that are able to learn accurate classifiers while preserving the domain structure provided through the rank information. We apply these methods to the task of detecting abnormal cortical regions in the MRIs of patients suffering from focal epilepsy whose MRI were read as normal by expert neuroradiologists. In addition to the noisy labels provided by the results of surgical resection, we employ the results of an invasive intracranial-EEG exam as an additional source of label information. Our proposed methods are able to successfully detect abnormal regions for all patients in our dataset and achieve a higher performance as compared to baseline methods.
no_new_dataset
0.940024
1608.00182
Peng Tang
Peng Tang, Xinggang Wang, Baoguang Shi, Xiang Bai, Wenyu Liu, Zhuowen Tu
Deep FisherNet for Object Classification
submitted to NIPS 2016
null
null
null
cs.CV cs.LG
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Despite the great success of convolutional neural networks (CNN) for the image classification task on datasets like Cifar and ImageNet, CNN's representation power is still somewhat limited in dealing with object images that have large variation in size and clutter, where Fisher Vector (FV) has shown to be an effective encoding strategy. FV encodes an image by aggregating local descriptors with a universal generative Gaussian Mixture Model (GMM). FV however has limited learning capability and its parameters are mostly fixed after constructing the codebook. To combine together the best of the two worlds, we propose in this paper a neural network structure with FV layer being part of an end-to-end trainable system that is differentiable; we name our network FisherNet that is learnable using backpropagation. Our proposed FisherNet combines convolutional neural network training and Fisher Vector encoding in a single end-to-end structure. We observe a clear advantage of FisherNet over plain CNN and standard FV in terms of both classification accuracy and computational efficiency on the challenging PASCAL VOC object classification task.
[ { "version": "v1", "created": "Sun, 31 Jul 2016 03:56:30 GMT" } ]
2016-08-02T00:00:00
[ [ "Tang", "Peng", "" ], [ "Wang", "Xinggang", "" ], [ "Shi", "Baoguang", "" ], [ "Bai", "Xiang", "" ], [ "Liu", "Wenyu", "" ], [ "Tu", "Zhuowen", "" ] ]
TITLE: Deep FisherNet for Object Classification ABSTRACT: Despite the great success of convolutional neural networks (CNN) for the image classification task on datasets like Cifar and ImageNet, CNN's representation power is still somewhat limited in dealing with object images that have large variation in size and clutter, where Fisher Vector (FV) has shown to be an effective encoding strategy. FV encodes an image by aggregating local descriptors with a universal generative Gaussian Mixture Model (GMM). FV however has limited learning capability and its parameters are mostly fixed after constructing the codebook. To combine together the best of the two worlds, we propose in this paper a neural network structure with FV layer being part of an end-to-end trainable system that is differentiable; we name our network FisherNet that is learnable using backpropagation. Our proposed FisherNet combines convolutional neural network training and Fisher Vector encoding in a single end-to-end structure. We observe a clear advantage of FisherNet over plain CNN and standard FV in terms of both classification accuracy and computational efficiency on the challenging PASCAL VOC object classification task.
no_new_dataset
0.948822
1608.00199
Soumitra Samanta
Soumitra Samanta and Bhabatosh Chanda
A Data-driven Approach for Human Pose Tracking Based on Spatio-temporal Pictorial Structure
null
null
null
null
cs.CV
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
In this paper, we present a data-driven approach for human pose tracking in video data. We formulate the human pose tracking problem as a discrete optimization problem based on spatio-temporal pictorial structure model and solve this problem in a greedy framework very efficiently. We propose the model to track the human pose by combining the human pose estimation from single image and traditional object tracking in a video. Our pose tracking objective function consists of the following terms: likeliness of appearance of a part within a frame, temporal displacement of the part from previous frame to the current frame, and the spatial dependency of a part with its parent in the graph structure. Experimental evaluation on benchmark datasets (VideoPose2, Poses in the Wild and Outdoor Pose) as well as on our newly build ICDPose dataset shows the usefulness of our proposed method.
[ { "version": "v1", "created": "Sun, 31 Jul 2016 08:50:47 GMT" } ]
2016-08-02T00:00:00
[ [ "Samanta", "Soumitra", "" ], [ "Chanda", "Bhabatosh", "" ] ]
TITLE: A Data-driven Approach for Human Pose Tracking Based on Spatio-temporal Pictorial Structure ABSTRACT: In this paper, we present a data-driven approach for human pose tracking in video data. We formulate the human pose tracking problem as a discrete optimization problem based on spatio-temporal pictorial structure model and solve this problem in a greedy framework very efficiently. We propose the model to track the human pose by combining the human pose estimation from single image and traditional object tracking in a video. Our pose tracking objective function consists of the following terms: likeliness of appearance of a part within a frame, temporal displacement of the part from previous frame to the current frame, and the spatial dependency of a part with its parent in the graph structure. Experimental evaluation on benchmark datasets (VideoPose2, Poses in the Wild and Outdoor Pose) as well as on our newly build ICDPose dataset shows the usefulness of our proposed method.
new_dataset
0.954984
1608.00203
Balint Antal
Balint Antal
Automatic 3D Point Set Reconstruction from Stereo Laparoscopic Images using Deep Neural Networks
In Proceedings of the 6th International Joint Conference on Pervasive and Embedded Computing and Communication Systems (PECCS 2016), pages 116-121 ISBN: 978-989-758-195-3
null
null
null
cs.CV
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
In this paper, an automatic approach to predict 3D coordinates from stereo laparoscopic images is presented. The approach maps a vector of pixel intensities to 3D coordinates through training a six layer deep neural network. The architectural aspects of the approach is presented and in detail and the method is evaluated on a publicly available dataset with promising results.
[ { "version": "v1", "created": "Sun, 31 Jul 2016 09:28:28 GMT" } ]
2016-08-02T00:00:00
[ [ "Antal", "Balint", "" ] ]
TITLE: Automatic 3D Point Set Reconstruction from Stereo Laparoscopic Images using Deep Neural Networks ABSTRACT: In this paper, an automatic approach to predict 3D coordinates from stereo laparoscopic images is presented. The approach maps a vector of pixel intensities to 3D coordinates through training a six layer deep neural network. The architectural aspects of the approach is presented and in detail and the method is evaluated on a publicly available dataset with promising results.
no_new_dataset
0.947527
1608.00207
Zhiwen Shao
Zhiwen Shao, Shouhong Ding, Yiru Zhao, Qinchuan Zhang, Lizhuang Ma
Learning deep representation from coarse to fine for face alignment
This paper is accepted by 2016 IEEE International Conference on Multimedia and Expo (ICME)
null
null
null
cs.CV
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
In this paper, we propose a novel face alignment method that trains deep convolutional network from coarse to fine. It divides given landmarks into principal subset and elaborate subset. We firstly keep a large weight for principal subset to make our network primarily predict their locations while slightly take elaborate subset into account. Next the weight of principal subset is gradually decreased until two subsets have equivalent weights. This process contributes to learn a good initial model and search the optimal model smoothly to avoid missing fairly good intermediate models in subsequent procedures. On the challenging COFW dataset [1], our method achieves 6.33% mean error with a reduction of 21.37% compared with the best previous result [2].
[ { "version": "v1", "created": "Sun, 31 Jul 2016 11:02:40 GMT" } ]
2016-08-02T00:00:00
[ [ "Shao", "Zhiwen", "" ], [ "Ding", "Shouhong", "" ], [ "Zhao", "Yiru", "" ], [ "Zhang", "Qinchuan", "" ], [ "Ma", "Lizhuang", "" ] ]
TITLE: Learning deep representation from coarse to fine for face alignment ABSTRACT: In this paper, we propose a novel face alignment method that trains deep convolutional network from coarse to fine. It divides given landmarks into principal subset and elaborate subset. We firstly keep a large weight for principal subset to make our network primarily predict their locations while slightly take elaborate subset into account. Next the weight of principal subset is gradually decreased until two subsets have equivalent weights. This process contributes to learn a good initial model and search the optimal model smoothly to avoid missing fairly good intermediate models in subsequent procedures. On the challenging COFW dataset [1], our method achieves 6.33% mean error with a reduction of 21.37% compared with the best previous result [2].
no_new_dataset
0.953232
1608.00218
Ilija Ilievski
Ilija Ilievski and Jiashi Feng
Hyperparameter Transfer Learning through Surrogate Alignment for Efficient Deep Neural Network Training
null
null
null
null
cs.LG cs.CV cs.NE stat.ML
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Recently, several optimization methods have been successfully applied to the hyperparameter optimization of deep neural networks (DNNs). The methods work by modeling the joint distribution of hyperparameter values and corresponding error. Those methods become less practical when applied to modern DNNs whose training may take a few days and thus one cannot collect sufficient observations to accurately model the distribution. To address this challenging issue, we propose a method that learns to transfer optimal hyperparameter values for a small source dataset to hyperparameter values with comparable performance on a dataset of interest. As opposed to existing transfer learning methods, our proposed method does not use hand-designed features. Instead, it uses surrogates to model the hyperparameter-error distributions of the two datasets and trains a neural network to learn the transfer function. Extensive experiments on three CV benchmark datasets clearly demonstrate the efficiency of our method.
[ { "version": "v1", "created": "Sun, 31 Jul 2016 14:09:17 GMT" } ]
2016-08-02T00:00:00
[ [ "Ilievski", "Ilija", "" ], [ "Feng", "Jiashi", "" ] ]
TITLE: Hyperparameter Transfer Learning through Surrogate Alignment for Efficient Deep Neural Network Training ABSTRACT: Recently, several optimization methods have been successfully applied to the hyperparameter optimization of deep neural networks (DNNs). The methods work by modeling the joint distribution of hyperparameter values and corresponding error. Those methods become less practical when applied to modern DNNs whose training may take a few days and thus one cannot collect sufficient observations to accurately model the distribution. To address this challenging issue, we propose a method that learns to transfer optimal hyperparameter values for a small source dataset to hyperparameter values with comparable performance on a dataset of interest. As opposed to existing transfer learning methods, our proposed method does not use hand-designed features. Instead, it uses surrogates to model the hyperparameter-error distributions of the two datasets and trains a neural network to learn the transfer function. Extensive experiments on three CV benchmark datasets clearly demonstrate the efficiency of our method.
no_new_dataset
0.947914
1608.00310
Abir Das
Rameswar Panda, Abir Das, Amit K. Roy-Chowdhury
Video Summarization in a Multi-View Camera Network
Accepted in ICPR 2016
null
null
null
cs.CV
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
While most existing video summarization approaches aim to extract an informative summary of a single video, we propose a novel framework for summarizing multi-view videos by exploiting both intra- and inter-view content correlations in a joint embedding space. We learn the embedding by minimizing an objective function that has two terms: one due to intra-view correlations and another due to inter-view correlations across the multiple views. The solution can be obtained directly by solving one Eigen-value problem that is linear in the number of multi-view videos. We then employ a sparse representative selection approach over the learned embedding space to summarize the multi-view videos. Experimental results on several benchmark datasets demonstrate that our proposed approach clearly outperforms the state-of-the-art.
[ { "version": "v1", "created": "Mon, 1 Aug 2016 03:42:07 GMT" } ]
2016-08-02T00:00:00
[ [ "Panda", "Rameswar", "" ], [ "Das", "Abir", "" ], [ "Roy-Chowdhury", "Amit K.", "" ] ]
TITLE: Video Summarization in a Multi-View Camera Network ABSTRACT: While most existing video summarization approaches aim to extract an informative summary of a single video, we propose a novel framework for summarizing multi-view videos by exploiting both intra- and inter-view content correlations in a joint embedding space. We learn the embedding by minimizing an objective function that has two terms: one due to intra-view correlations and another due to inter-view correlations across the multiple views. The solution can be obtained directly by solving one Eigen-value problem that is linear in the number of multi-view videos. We then employ a sparse representative selection approach over the learned embedding space to summarize the multi-view videos. Experimental results on several benchmark datasets demonstrate that our proposed approach clearly outperforms the state-of-the-art.
no_new_dataset
0.944382
1608.00462
Marco De Nadai
Marco De Nadai, Radu L. Vieriu, Gloria Zen, Stefan Dragicevic, Nikhil Naik, Michele Caraviello, Cesar A. Hidalgo, Nicu Sebe, Bruno Lepri
Are Safer Looking Neighborhoods More Lively? A Multimodal Investigation into Urban Life
To appear in the Proceedings of ACM Multimedia Conference (MM), 2016. October 15 - 19, 2016, Amsterdam, Netherlands
null
null
null
cs.CY cs.SI physics.soc-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Policy makers, urban planners, architects, sociologists, and economists are interested in creating urban areas that are both lively and safe. But are the safety and liveliness of neighborhoods independent characteristics? Or are they just two sides of the same coin? In a world where people avoid unsafe looking places, neighborhoods that look unsafe will be less lively, and will fail to harness the natural surveillance of human activity. But in a world where the preference for safe looking neighborhoods is small, the connection between the perception of safety and liveliness will be either weak or nonexistent. In this paper we explore the connection between the levels of activity and the perception of safety of neighborhoods in two major Italian cities by combining mobile phone data (as a proxy for activity or liveliness) with scores of perceived safety estimated using a Convolutional Neural Network trained on a dataset of Google Street View images scored using a crowdsourced visual perception survey. We find that: (i) safer looking neighborhoods are more active than what is expected from their population density, employee density, and distance to the city centre; and (ii) that the correlation between appearance of safety and activity is positive, strong, and significant, for females and people over 50, but negative for people under 30, suggesting that the behavioral impact of perception depends on the demographic of the population. Finally, we use occlusion techniques to identify the urban features that contribute to the appearance of safety, finding that greenery and street facing windows contribute to a positive appearance of safety (in agreement with Oscar Newman's defensible space theory). These results suggest that urban appearance modulates levels of human activity and, consequently, a neighborhood's rate of natural surveillance.
[ { "version": "v1", "created": "Mon, 1 Aug 2016 15:06:40 GMT" } ]
2016-08-02T00:00:00
[ [ "De Nadai", "Marco", "" ], [ "Vieriu", "Radu L.", "" ], [ "Zen", "Gloria", "" ], [ "Dragicevic", "Stefan", "" ], [ "Naik", "Nikhil", "" ], [ "Caraviello", "Michele", "" ], [ "Hidalgo", "Cesar A.", "" ], [ "Sebe", "Nicu", "" ], [ "Lepri", "Bruno", "" ] ]
TITLE: Are Safer Looking Neighborhoods More Lively? A Multimodal Investigation into Urban Life ABSTRACT: Policy makers, urban planners, architects, sociologists, and economists are interested in creating urban areas that are both lively and safe. But are the safety and liveliness of neighborhoods independent characteristics? Or are they just two sides of the same coin? In a world where people avoid unsafe looking places, neighborhoods that look unsafe will be less lively, and will fail to harness the natural surveillance of human activity. But in a world where the preference for safe looking neighborhoods is small, the connection between the perception of safety and liveliness will be either weak or nonexistent. In this paper we explore the connection between the levels of activity and the perception of safety of neighborhoods in two major Italian cities by combining mobile phone data (as a proxy for activity or liveliness) with scores of perceived safety estimated using a Convolutional Neural Network trained on a dataset of Google Street View images scored using a crowdsourced visual perception survey. We find that: (i) safer looking neighborhoods are more active than what is expected from their population density, employee density, and distance to the city centre; and (ii) that the correlation between appearance of safety and activity is positive, strong, and significant, for females and people over 50, but negative for people under 30, suggesting that the behavioral impact of perception depends on the demographic of the population. Finally, we use occlusion techniques to identify the urban features that contribute to the appearance of safety, finding that greenery and street facing windows contribute to a positive appearance of safety (in agreement with Oscar Newman's defensible space theory). These results suggest that urban appearance modulates levels of human activity and, consequently, a neighborhood's rate of natural surveillance.
no_new_dataset
0.943556
1608.00507
Jianming Zhang
Jianming Zhang, Zhe Lin, Jonathan Brandt, Xiaohui Shen, Stan Sclaroff
Top-down Neural Attention by Excitation Backprop
A shorter version of this paper is accepted at ECCV, 2016 (oral)
null
null
null
cs.CV
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We aim to model the top-down attention of a Convolutional Neural Network (CNN) classifier for generating task-specific attention maps. Inspired by a top-down human visual attention model, we propose a new backpropagation scheme, called Excitation Backprop, to pass along top-down signals downwards in the network hierarchy via a probabilistic Winner-Take-All process. Furthermore, we introduce the concept of contrastive attention to make the top-down attention maps more discriminative. In experiments, we demonstrate the accuracy and generalizability of our method in weakly supervised localization tasks on the MS COCO, PASCAL VOC07 and ImageNet datasets. The usefulness of our method is further validated in the text-to-region association task. On the Flickr30k Entities dataset, we achieve promising performance in phrase localization by leveraging the top-down attention of a CNN model that has been trained on weakly labeled web images.
[ { "version": "v1", "created": "Mon, 1 Aug 2016 17:49:57 GMT" } ]
2016-08-02T00:00:00
[ [ "Zhang", "Jianming", "" ], [ "Lin", "Zhe", "" ], [ "Brandt", "Jonathan", "" ], [ "Shen", "Xiaohui", "" ], [ "Sclaroff", "Stan", "" ] ]
TITLE: Top-down Neural Attention by Excitation Backprop ABSTRACT: We aim to model the top-down attention of a Convolutional Neural Network (CNN) classifier for generating task-specific attention maps. Inspired by a top-down human visual attention model, we propose a new backpropagation scheme, called Excitation Backprop, to pass along top-down signals downwards in the network hierarchy via a probabilistic Winner-Take-All process. Furthermore, we introduce the concept of contrastive attention to make the top-down attention maps more discriminative. In experiments, we demonstrate the accuracy and generalizability of our method in weakly supervised localization tasks on the MS COCO, PASCAL VOC07 and ImageNet datasets. The usefulness of our method is further validated in the text-to-region association task. On the Flickr30k Entities dataset, we achieve promising performance in phrase localization by leveraging the top-down attention of a CNN model that has been trained on weakly labeled web images.
no_new_dataset
0.951278
1608.00525
Varun Nagaraja
Varun K. Nagaraja, Vlad I. Morariu, Larry S. Davis
Modeling Context Between Objects for Referring Expression Understanding
To appear at ECCV 16
null
null
null
cs.CV
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Referring expressions usually describe an object using properties of the object and relationships of the object with other objects. We propose a technique that integrates context between objects to understand referring expressions. Our approach uses an LSTM to learn the probability of a referring expression, with input features from a region and a context region. The context regions are discovered using multiple-instance learning (MIL) since annotations for context objects are generally not available for training. We utilize max-margin based MIL objective functions for training the LSTM. Experiments on the Google RefExp and UNC RefExp datasets show that modeling context between objects provides better performance than modeling only object properties. We also qualitatively show that our technique can ground a referring expression to its referred region along with the supporting context region.
[ { "version": "v1", "created": "Mon, 1 Aug 2016 19:03:27 GMT" } ]
2016-08-02T00:00:00
[ [ "Nagaraja", "Varun K.", "" ], [ "Morariu", "Vlad I.", "" ], [ "Davis", "Larry S.", "" ] ]
TITLE: Modeling Context Between Objects for Referring Expression Understanding ABSTRACT: Referring expressions usually describe an object using properties of the object and relationships of the object with other objects. We propose a technique that integrates context between objects to understand referring expressions. Our approach uses an LSTM to learn the probability of a referring expression, with input features from a region and a context region. The context regions are discovered using multiple-instance learning (MIL) since annotations for context objects are generally not available for training. We utilize max-margin based MIL objective functions for training the LSTM. Experiments on the Google RefExp and UNC RefExp datasets show that modeling context between objects provides better performance than modeling only object properties. We also qualitatively show that our technique can ground a referring expression to its referred region along with the supporting context region.
no_new_dataset
0.950503
1608.00550
Ping Li
Ping Li and Cun-Hui Zhang
Theory of the GMM Kernel
null
null
null
null
stat.ME cs.DS cs.IT cs.LG math.IT
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We develop some theoretical results for a robust similarity measure named "generalized min-max" (GMM). This similarity has direct applications in machine learning as a positive definite kernel and can be efficiently computed via probabilistic hashing. Owing to the discrete nature, the hashed values can also be used for efficient near neighbor search. We prove the theoretical limit of GMM and the consistency result, assuming that the data follow an elliptical distribution, which is a very general family of distributions and includes the multivariate $t$-distribution as a special case. The consistency result holds as long as the data have bounded first moment (an assumption which essentially holds for datasets commonly encountered in practice). Furthermore, we establish the asymptotic normality of GMM. Compared to the "cosine" similarity which is routinely adopted in current practice in statistics and machine learning, the consistency of GMM requires much weaker conditions. Interestingly, when the data follow the $t$-distribution with $\nu$ degrees of freedom, GMM typically provides a better measure of similarity than "cosine" roughly when $\nu<8$ (which is already very close to normal). These theoretical results will help explain the recent success of GMM in learning tasks.
[ { "version": "v1", "created": "Mon, 1 Aug 2016 19:45:57 GMT" } ]
2016-08-02T00:00:00
[ [ "Li", "Ping", "" ], [ "Zhang", "Cun-Hui", "" ] ]
TITLE: Theory of the GMM Kernel ABSTRACT: We develop some theoretical results for a robust similarity measure named "generalized min-max" (GMM). This similarity has direct applications in machine learning as a positive definite kernel and can be efficiently computed via probabilistic hashing. Owing to the discrete nature, the hashed values can also be used for efficient near neighbor search. We prove the theoretical limit of GMM and the consistency result, assuming that the data follow an elliptical distribution, which is a very general family of distributions and includes the multivariate $t$-distribution as a special case. The consistency result holds as long as the data have bounded first moment (an assumption which essentially holds for datasets commonly encountered in practice). Furthermore, we establish the asymptotic normality of GMM. Compared to the "cosine" similarity which is routinely adopted in current practice in statistics and machine learning, the consistency of GMM requires much weaker conditions. Interestingly, when the data follow the $t$-distribution with $\nu$ degrees of freedom, GMM typically provides a better measure of similarity than "cosine" roughly when $\nu<8$ (which is already very close to normal). These theoretical results will help explain the recent success of GMM in learning tasks.
no_new_dataset
0.948822
1408.0517
Vijay Gadepally
Vijay Gadepally and Jeremy Kepner
Big Data Dimensional Analysis
From IEEE HPEC 2014
null
10.1109/HPEC.2014.7040944
null
cs.DB cs.DC
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The ability to collect and analyze large amounts of data is a growing problem within the scientific community. The growing gap between data and users calls for innovative tools that address the challenges faced by big data volume, velocity and variety. One of the main challenges associated with big data variety is automatically understanding the underlying structures and patterns of the data. Such an understanding is required as a pre-requisite to the application of advanced analytics to the data. Further, big data sets often contain anomalies and errors that are difficult to know a priori. Current approaches to understanding data structure are drawn from the traditional database ontology design. These approaches are effective, but often require too much human involvement to be effective for the volume, velocity and variety of data encountered by big data systems. Dimensional Data Analysis (DDA) is a proposed technique that allows big data analysts to quickly understand the overall structure of a big dataset, determine anomalies. DDA exploits structures that exist in a wide class of data to quickly determine the nature of the data and its statical anomalies. DDA leverages existing schemas that are employed in big data databases today. This paper presents DDA, applies it to a number of data sets, and measures its performance. The overhead of DDA is low and can be applied to existing big data systems without greatly impacting their computing requirements.
[ { "version": "v1", "created": "Sun, 3 Aug 2014 17:22:01 GMT" } ]
2016-08-01T00:00:00
[ [ "Gadepally", "Vijay", "" ], [ "Kepner", "Jeremy", "" ] ]
TITLE: Big Data Dimensional Analysis ABSTRACT: The ability to collect and analyze large amounts of data is a growing problem within the scientific community. The growing gap between data and users calls for innovative tools that address the challenges faced by big data volume, velocity and variety. One of the main challenges associated with big data variety is automatically understanding the underlying structures and patterns of the data. Such an understanding is required as a pre-requisite to the application of advanced analytics to the data. Further, big data sets often contain anomalies and errors that are difficult to know a priori. Current approaches to understanding data structure are drawn from the traditional database ontology design. These approaches are effective, but often require too much human involvement to be effective for the volume, velocity and variety of data encountered by big data systems. Dimensional Data Analysis (DDA) is a proposed technique that allows big data analysts to quickly understand the overall structure of a big dataset, determine anomalies. DDA exploits structures that exist in a wide class of data to quickly determine the nature of the data and its statical anomalies. DDA leverages existing schemas that are employed in big data databases today. This paper presents DDA, applies it to a number of data sets, and measures its performance. The overhead of DDA is low and can be applied to existing big data systems without greatly impacting their computing requirements.
no_new_dataset
0.949435
1509.06585
Vincent Labatut
Jean-Val\`ere Cossu (LIA), Vincent Labatut (LIA), Nicolas Dugu\'e (UO)
A Review of Features for the Discrimination of Twitter Users: Application to the Prediction of Offline Influence
null
Social Network Analysis and Mining, Springer, 2016, 6 (1), pp.25
10.1007/s13278-016-0329-x
null
cs.CL cs.SI
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Many works related to Twitter aim at characterizing its users in some way: role on the service (spammers, bots, organizations, etc.), nature of the user (socio-professional category, age, etc.), topics of interest , and others. However, for a given user classification problem, it is very difficult to select a set of appropriate features, because the many features described in the literature are very heterogeneous, with name overlaps and collisions, and numerous very close variants. In this article, we review a wide range of such features. In order to present a clear state-of-the-art description, we unify their names, definitions and relationships, and we propose a new, neutral, typology. We then illustrate the interest of our review by applying a selection of these features to the offline influence detection problem. This task consists in identifying users which are influential in real-life, based on their Twitter account and related data. We show that most features deemed efficient to predict online influence, such as the numbers of retweets and followers, are not relevant to this problem. However, We propose several content-based approaches to label Twitter users as Influencers or not. We also rank them according to a predicted influence level. Our proposals are evaluated over the CLEF RepLab 2014 dataset, and outmatch state-of-the-art methods.
[ { "version": "v1", "created": "Tue, 22 Sep 2015 13:12:34 GMT" }, { "version": "v2", "created": "Wed, 27 Jul 2016 13:19:33 GMT" }, { "version": "v3", "created": "Fri, 29 Jul 2016 08:02:34 GMT" } ]
2016-08-01T00:00:00
[ [ "Cossu", "Jean-Valère", "", "LIA" ], [ "Labatut", "Vincent", "", "LIA" ], [ "Dugué", "Nicolas", "", "UO" ] ]
TITLE: A Review of Features for the Discrimination of Twitter Users: Application to the Prediction of Offline Influence ABSTRACT: Many works related to Twitter aim at characterizing its users in some way: role on the service (spammers, bots, organizations, etc.), nature of the user (socio-professional category, age, etc.), topics of interest , and others. However, for a given user classification problem, it is very difficult to select a set of appropriate features, because the many features described in the literature are very heterogeneous, with name overlaps and collisions, and numerous very close variants. In this article, we review a wide range of such features. In order to present a clear state-of-the-art description, we unify their names, definitions and relationships, and we propose a new, neutral, typology. We then illustrate the interest of our review by applying a selection of these features to the offline influence detection problem. This task consists in identifying users which are influential in real-life, based on their Twitter account and related data. We show that most features deemed efficient to predict online influence, such as the numbers of retweets and followers, are not relevant to this problem. However, We propose several content-based approaches to label Twitter users as Influencers or not. We also rank them according to a predicted influence level. Our proposals are evaluated over the CLEF RepLab 2014 dataset, and outmatch state-of-the-art methods.
no_new_dataset
0.941385
1601.05347
M. Saquib Sarfraz
M. Saquib Sarfraz and Rainer Stiefelhagen
Deep Perceptual Mapping for Cross-Modal Face Recognition
This is the extended version (invited IJCV submission) with new results of our previous submission (arXiv:1507.02879)
null
10.1007/s11263-016-0933-2
null
cs.CV
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Cross modal face matching between the thermal and visible spectrum is a much desired capability for night-time surveillance and security applications. Due to a very large modality gap, thermal-to-visible face recognition is one of the most challenging face matching problem. In this paper, we present an approach to bridge this modality gap by a significant margin. Our approach captures the highly non-linear relationship between the two modalities by using a deep neural network. Our model attempts to learn a non-linear mapping from visible to thermal spectrum while preserving the identity information. We show substantive performance improvement on three difficult thermal-visible face datasets. The presented approach improves the state-of-the-art by more than 10\% on UND-X1 dataset and by more than 15-30\% on NVESD dataset in terms of Rank-1 identification. Our method bridges the drop in performance due to the modality gap by more than 40\%.
[ { "version": "v1", "created": "Wed, 20 Jan 2016 17:49:11 GMT" }, { "version": "v2", "created": "Thu, 7 Jul 2016 07:30:51 GMT" } ]
2016-08-01T00:00:00
[ [ "Sarfraz", "M. Saquib", "" ], [ "Stiefelhagen", "Rainer", "" ] ]
TITLE: Deep Perceptual Mapping for Cross-Modal Face Recognition ABSTRACT: Cross modal face matching between the thermal and visible spectrum is a much desired capability for night-time surveillance and security applications. Due to a very large modality gap, thermal-to-visible face recognition is one of the most challenging face matching problem. In this paper, we present an approach to bridge this modality gap by a significant margin. Our approach captures the highly non-linear relationship between the two modalities by using a deep neural network. Our model attempts to learn a non-linear mapping from visible to thermal spectrum while preserving the identity information. We show substantive performance improvement on three difficult thermal-visible face datasets. The presented approach improves the state-of-the-art by more than 10\% on UND-X1 dataset and by more than 15-30\% on NVESD dataset in terms of Rank-1 identification. Our method bridges the drop in performance due to the modality gap by more than 40\%.
no_new_dataset
0.955361
1601.07213
Alexander Ororbia II
Alexander G. Ororbia II, C. Lee Giles, and Daniel Kifer
Unifying Adversarial Training Algorithms with Flexible Deep Data Gradient Regularization
null
null
null
null
cs.LG cs.NE
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Many previous proposals for adversarial training of deep neural nets have included di- rectly modifying the gradient, training on a mix of original and adversarial examples, using contractive penalties, and approximately optimizing constrained adversarial ob- jective functions. In this paper, we show these proposals are actually all instances of optimizing a general, regularized objective we call DataGrad. Our proposed DataGrad framework, which can be viewed as a deep extension of the layerwise contractive au- toencoder penalty, cleanly simplifies prior work and easily allows extensions such as adversarial training with multi-task cues. In our experiments, we find that the deep gra- dient regularization of DataGrad (which also has L1 and L2 flavors of regularization) outperforms alternative forms of regularization, including classical L1, L2, and multi- task, both on the original dataset as well as on adversarial sets. Furthermore, we find that combining multi-task optimization with DataGrad adversarial training results in the most robust performance.
[ { "version": "v1", "created": "Tue, 26 Jan 2016 22:41:13 GMT" }, { "version": "v2", "created": "Tue, 9 Feb 2016 20:40:13 GMT" }, { "version": "v3", "created": "Fri, 29 Jul 2016 15:36:19 GMT" } ]
2016-08-01T00:00:00
[ [ "Ororbia", "Alexander G.", "II" ], [ "Giles", "C. Lee", "" ], [ "Kifer", "Daniel", "" ] ]
TITLE: Unifying Adversarial Training Algorithms with Flexible Deep Data Gradient Regularization ABSTRACT: Many previous proposals for adversarial training of deep neural nets have included di- rectly modifying the gradient, training on a mix of original and adversarial examples, using contractive penalties, and approximately optimizing constrained adversarial ob- jective functions. In this paper, we show these proposals are actually all instances of optimizing a general, regularized objective we call DataGrad. Our proposed DataGrad framework, which can be viewed as a deep extension of the layerwise contractive au- toencoder penalty, cleanly simplifies prior work and easily allows extensions such as adversarial training with multi-task cues. In our experiments, we find that the deep gra- dient regularization of DataGrad (which also has L1 and L2 flavors of regularization) outperforms alternative forms of regularization, including classical L1, L2, and multi- task, both on the original dataset as well as on adversarial sets. Furthermore, we find that combining multi-task optimization with DataGrad adversarial training results in the most robust performance.
no_new_dataset
0.948442
1603.04992
Ravi Garg
Ravi Garg, Vijay Kumar BG, Gustavo Carneiro, Ian Reid
Unsupervised CNN for Single View Depth Estimation: Geometry to the Rescue
Accepted for publication at ECCV 2016
null
null
null
cs.CV
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
A significant weakness of most current deep Convolutional Neural Networks is the need to train them using vast amounts of manu- ally labelled data. In this work we propose a unsupervised framework to learn a deep convolutional neural network for single view depth predic- tion, without requiring a pre-training stage or annotated ground truth depths. We achieve this by training the network in a manner analogous to an autoencoder. At training time we consider a pair of images, source and target, with small, known camera motion between the two such as a stereo pair. We train the convolutional encoder for the task of predicting the depth map for the source image. To do so, we explicitly generate an inverse warp of the target image using the predicted depth and known inter-view displacement, to reconstruct the source image; the photomet- ric error in the reconstruction is the reconstruction loss for the encoder. The acquisition of this training data is considerably simpler than for equivalent systems, requiring no manual annotation, nor calibration of depth sensor to camera. We show that our network trained on less than half of the KITTI dataset (without any further augmentation) gives com- parable performance to that of the state of art supervised methods for single view depth estimation.
[ { "version": "v1", "created": "Wed, 16 Mar 2016 08:57:15 GMT" }, { "version": "v2", "created": "Fri, 29 Jul 2016 03:20:46 GMT" } ]
2016-08-01T00:00:00
[ [ "Garg", "Ravi", "" ], [ "BG", "Vijay Kumar", "" ], [ "Carneiro", "Gustavo", "" ], [ "Reid", "Ian", "" ] ]
TITLE: Unsupervised CNN for Single View Depth Estimation: Geometry to the Rescue ABSTRACT: A significant weakness of most current deep Convolutional Neural Networks is the need to train them using vast amounts of manu- ally labelled data. In this work we propose a unsupervised framework to learn a deep convolutional neural network for single view depth predic- tion, without requiring a pre-training stage or annotated ground truth depths. We achieve this by training the network in a manner analogous to an autoencoder. At training time we consider a pair of images, source and target, with small, known camera motion between the two such as a stereo pair. We train the convolutional encoder for the task of predicting the depth map for the source image. To do so, we explicitly generate an inverse warp of the target image using the predicted depth and known inter-view displacement, to reconstruct the source image; the photomet- ric error in the reconstruction is the reconstruction loss for the encoder. The acquisition of this training data is considerably simpler than for equivalent systems, requiring no manual annotation, nor calibration of depth sensor to camera. We show that our network trained on less than half of the KITTI dataset (without any further augmentation) gives com- parable performance to that of the state of art supervised methods for single view depth estimation.
no_new_dataset
0.947332
1603.09114
Eduard Trulls
Kwang Moo Yi and Eduard Trulls and Vincent Lepetit and Pascal Fua
LIFT: Learned Invariant Feature Transform
Accepted to ECCV 2016 (spotlight)
null
null
null
cs.CV
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We introduce a novel Deep Network architecture that implements the full feature point handling pipeline, that is, detection, orientation estimation, and feature description. While previous works have successfully tackled each one of these problems individually, we show how to learn to do all three in a unified manner while preserving end-to-end differentiability. We then demonstrate that our Deep pipeline outperforms state-of-the-art methods on a number of benchmark datasets, without the need of retraining.
[ { "version": "v1", "created": "Wed, 30 Mar 2016 10:33:18 GMT" }, { "version": "v2", "created": "Fri, 29 Jul 2016 15:29:39 GMT" } ]
2016-08-01T00:00:00
[ [ "Yi", "Kwang Moo", "" ], [ "Trulls", "Eduard", "" ], [ "Lepetit", "Vincent", "" ], [ "Fua", "Pascal", "" ] ]
TITLE: LIFT: Learned Invariant Feature Transform ABSTRACT: We introduce a novel Deep Network architecture that implements the full feature point handling pipeline, that is, detection, orientation estimation, and feature description. While previous works have successfully tackled each one of these problems individually, we show how to learn to do all three in a unified manner while preserving end-to-end differentiability. We then demonstrate that our Deep pipeline outperforms state-of-the-art methods on a number of benchmark datasets, without the need of retraining.
no_new_dataset
0.945147
1605.02964
Abhilash Srikantha
Abhilash Srikantha, Juergen Gall
Weakly Supervised Learning of Affordances
null
null
null
null
cs.CV
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Localizing functional regions of objects or affordances is an important aspect of scene understanding. In this work, we cast the problem of affordance segmentation as that of semantic image segmentation. In order to explore various levels of supervision, we introduce a pixel-annotated affordance dataset of 3090 images containing 9916 object instances with rich contextual information in terms of human-object interactions. We use a deep convolutional neural network within an expectation maximization framework to take advantage of weakly labeled data like image level annotations or keypoint annotations. We show that a further reduction in supervision is possible with a minimal loss in performance when human pose is used as context.
[ { "version": "v1", "created": "Tue, 10 May 2016 12:04:07 GMT" }, { "version": "v2", "created": "Fri, 29 Jul 2016 13:46:59 GMT" } ]
2016-08-01T00:00:00
[ [ "Srikantha", "Abhilash", "" ], [ "Gall", "Juergen", "" ] ]
TITLE: Weakly Supervised Learning of Affordances ABSTRACT: Localizing functional regions of objects or affordances is an important aspect of scene understanding. In this work, we cast the problem of affordance segmentation as that of semantic image segmentation. In order to explore various levels of supervision, we introduce a pixel-annotated affordance dataset of 3090 images containing 9916 object instances with rich contextual information in terms of human-object interactions. We use a deep convolutional neural network within an expectation maximization framework to take advantage of weakly labeled data like image level annotations or keypoint annotations. We show that a further reduction in supervision is possible with a minimal loss in performance when human pose is used as context.
new_dataset
0.953275
1605.05081
Fabrizio Cei
The MEG Collaboration
Search for the Lepton Flavour Violating Decay $\mu^{+} \to e^+ \gamma$ with the Full Dataset of the MEG Experiment
30 pages, 31 figures
null
null
null
hep-ex physics.ins-det
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The final results of the search for the lepton flavour violating decay $\mu^{+} \rightarrow {\rm e^{+}} \gamma$ based on the full dataset collected by the MEG experiment at the Paul Scherrer Institut in the period 2009--2013 and totalling $7.5\times 10^{14}$ stopped muons on target are presented. No significant excess of events is observed in the dataset with respect to the expected background and a new upper limit on the branching ratio of this decay of $BR( \mu^{+} \rightarrow {\rm e^{+}} \gamma ) < 4.2 \times 10^{-13}$ (90\%\ confidence level) is established, which represents the most stringent limit on the existence of this decay to date.
[ { "version": "v1", "created": "Tue, 17 May 2016 09:52:20 GMT" }, { "version": "v2", "created": "Wed, 18 May 2016 07:08:36 GMT" }, { "version": "v3", "created": "Fri, 29 Jul 2016 09:39:29 GMT" } ]
2016-08-01T00:00:00
[ [ "The MEG Collaboration", "", "" ] ]
TITLE: Search for the Lepton Flavour Violating Decay $\mu^{+} \to e^+ \gamma$ with the Full Dataset of the MEG Experiment ABSTRACT: The final results of the search for the lepton flavour violating decay $\mu^{+} \rightarrow {\rm e^{+}} \gamma$ based on the full dataset collected by the MEG experiment at the Paul Scherrer Institut in the period 2009--2013 and totalling $7.5\times 10^{14}$ stopped muons on target are presented. No significant excess of events is observed in the dataset with respect to the expected background and a new upper limit on the branching ratio of this decay of $BR( \mu^{+} \rightarrow {\rm e^{+}} \gamma ) < 4.2 \times 10^{-13}$ (90\%\ confidence level) is established, which represents the most stringent limit on the existence of this decay to date.
no_new_dataset
0.941493
1605.08110
Ke Zhang
Ke Zhang, Wei-Lun Chao, Fei Sha, Kristen Grauman
Video Summarization with Long Short-term Memory
To appear in ECCV 2016
null
null
null
cs.CV cs.LG
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We propose a novel supervised learning technique for summarizing videos by automatically selecting keyframes or key subshots. Casting the problem as a structured prediction problem on sequential data, our main idea is to use Long Short-Term Memory (LSTM), a special type of recurrent neural networks to model the variable-range dependencies entailed in the task of video summarization. Our learning models attain the state-of-the-art results on two benchmark video datasets. Detailed analysis justifies the design of the models. In particular, we show that it is crucial to take into consideration the sequential structures in videos and model them. Besides advances in modeling techniques, we introduce techniques to address the need of a large number of annotated data for training complex learning models. There, our main idea is to exploit the existence of auxiliary annotated video datasets, albeit heterogeneous in visual styles and contents. Specifically, we show domain adaptation techniques can improve summarization by reducing the discrepancies in statistical properties across those datasets.
[ { "version": "v1", "created": "Thu, 26 May 2016 00:46:35 GMT" }, { "version": "v2", "created": "Fri, 29 Jul 2016 07:05:34 GMT" } ]
2016-08-01T00:00:00
[ [ "Zhang", "Ke", "" ], [ "Chao", "Wei-Lun", "" ], [ "Sha", "Fei", "" ], [ "Grauman", "Kristen", "" ] ]
TITLE: Video Summarization with Long Short-term Memory ABSTRACT: We propose a novel supervised learning technique for summarizing videos by automatically selecting keyframes or key subshots. Casting the problem as a structured prediction problem on sequential data, our main idea is to use Long Short-Term Memory (LSTM), a special type of recurrent neural networks to model the variable-range dependencies entailed in the task of video summarization. Our learning models attain the state-of-the-art results on two benchmark video datasets. Detailed analysis justifies the design of the models. In particular, we show that it is crucial to take into consideration the sequential structures in videos and model them. Besides advances in modeling techniques, we introduce techniques to address the need of a large number of annotated data for training complex learning models. There, our main idea is to exploit the existence of auxiliary annotated video datasets, albeit heterogeneous in visual styles and contents. Specifically, we show domain adaptation techniques can improve summarization by reducing the discrepancies in statistical properties across those datasets.
no_new_dataset
0.94256
1607.01650
Wenkun Zhang
Lei Li, Ailong Cai, Linyuan Wang, Bin Yan, Hanming Zhang, Zhizhong Zheng, Wenkun Zhang, Wanli Lu, Guoen Hu
Efficient Image Reconstruction and Practical Decomposition for Dual-energy Computed Tomography
19 pages, 5 figures, 2 tables
null
null
null
physics.med-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Dual-energy computed tomography (DECT) has shown great potential and promising applications in advanced imaging fields for its capabilities of material decomposition. However, image reconstructions and decompositions under sparse views dataset suffers severely from multi factors, such as insufficiencies of data, appearances of noise, and inconsistencies of observations. Under sparse views, conventional filtered back-projection type reconstruction methods fails to provide CT images with satisfying quality. Moreover, direct image decomposition is unstable and meet with noise boost even with full views dataset. This paper proposes an iterative image reconstruction algorithm and a practical image domain decomposition method for DECT. On one hand, the reconstruction algorithm is formulated as an optimization problem, which containing total variation regularization term and data fidelity term. The alternating direction method is utilized to design the corresponding algorithm which shows faster convergence speed compared with the existing ones. On the other hand, the image domain decomposition applies the penalized least square (PLS) estimation on decomposing the material mappings. The PLS includes linear combination term and the regularization term which enforces the smoothness on estimation images. The authors implement and evaluate the proposed joint method on real DECT projections and compare the method with typical and state-of-the-art reconstruction and decomposition methods. The experiments on dataset of an anthropomorphic head phantom show that our methods have advantages on noise suppression and edge reservation, without blurring the fine structures in the sinus area in the phantom. Compared to the existing approaches, our method achieves a superior performance on DECT imaging with respect to reconstruction accuracy and decomposition quality.
[ { "version": "v1", "created": "Wed, 6 Jul 2016 14:54:17 GMT" }, { "version": "v2", "created": "Fri, 29 Jul 2016 00:54:08 GMT" } ]
2016-08-01T00:00:00
[ [ "Li", "Lei", "" ], [ "Cai", "Ailong", "" ], [ "Wang", "Linyuan", "" ], [ "Yan", "Bin", "" ], [ "Zhang", "Hanming", "" ], [ "Zheng", "Zhizhong", "" ], [ "Zhang", "Wenkun", "" ], [ "Lu", "Wanli", "" ], [ "Hu", "Guoen", "" ] ]
TITLE: Efficient Image Reconstruction and Practical Decomposition for Dual-energy Computed Tomography ABSTRACT: Dual-energy computed tomography (DECT) has shown great potential and promising applications in advanced imaging fields for its capabilities of material decomposition. However, image reconstructions and decompositions under sparse views dataset suffers severely from multi factors, such as insufficiencies of data, appearances of noise, and inconsistencies of observations. Under sparse views, conventional filtered back-projection type reconstruction methods fails to provide CT images with satisfying quality. Moreover, direct image decomposition is unstable and meet with noise boost even with full views dataset. This paper proposes an iterative image reconstruction algorithm and a practical image domain decomposition method for DECT. On one hand, the reconstruction algorithm is formulated as an optimization problem, which containing total variation regularization term and data fidelity term. The alternating direction method is utilized to design the corresponding algorithm which shows faster convergence speed compared with the existing ones. On the other hand, the image domain decomposition applies the penalized least square (PLS) estimation on decomposing the material mappings. The PLS includes linear combination term and the regularization term which enforces the smoothness on estimation images. The authors implement and evaluate the proposed joint method on real DECT projections and compare the method with typical and state-of-the-art reconstruction and decomposition methods. The experiments on dataset of an anthropomorphic head phantom show that our methods have advantages on noise suppression and edge reservation, without blurring the fine structures in the sinus area in the phantom. Compared to the existing approaches, our method achieves a superior performance on DECT imaging with respect to reconstruction accuracy and decomposition quality.
no_new_dataset
0.944228
1607.07403
Sebastian Schelter
Sebastian Schelter, J\'er\^ome Kunegis
On the Ubiquity of Web Tracking: Insights from a Billion-Page Web Crawl
null
null
null
null
cs.SI
http://creativecommons.org/licenses/by-nc-sa/4.0/
We perform a large-scale analysis of third-party trackers on the World Wide Web from more than 3.5 billion web pages of the CommonCrawl 2012 corpus. We extract a dataset containing more than 140 million third-party embeddings in over 41 million domains. To the best of our knowledge, this constitutes the largest web tracking dataset collected so far, and exceeds related studies by more than an order of magnitude in the number of domains and web pages analyzed. We perform a large-scale study of online tracking, on three levels: (1) On a global level, we give a precise figure for the extent of tracking, give insights into the structure of the `online tracking sphere' and analyse which trackers are used by how many websites. (2) On a country-specific level, we analyse which trackers are used by websites in different countries, and identify the countries in which websites choose significantly different trackers than in the rest of the world. (3) We answer the question whether the content of websites influences the choice of trackers they use, leveraging more than 90 thousand categorized domains. In particular, we analyse whether highly privacy-critical websites make different choices of trackers than other websites. Based on the performed analyses, we confirm that trackers are widespread (as expected), and that a small number of trackers dominates the web (Google, Facebook and Twitter). In particular, the three tracking domains with the highest PageRank are all owned by Google. The only exception to this pattern are a few countries such as China and Russia. Our results suggest that this dominance is strongly associated with country-specific political factors such as freedom of the press. We also confirm that websites with highly privacy-critical content are less likely to contain trackers (60% vs 90% for other websites), even though the majority of them still do contain trackers.
[ { "version": "v1", "created": "Mon, 25 Jul 2016 18:49:20 GMT" }, { "version": "v2", "created": "Fri, 29 Jul 2016 06:29:26 GMT" } ]
2016-08-01T00:00:00
[ [ "Schelter", "Sebastian", "" ], [ "Kunegis", "Jérôme", "" ] ]
TITLE: On the Ubiquity of Web Tracking: Insights from a Billion-Page Web Crawl ABSTRACT: We perform a large-scale analysis of third-party trackers on the World Wide Web from more than 3.5 billion web pages of the CommonCrawl 2012 corpus. We extract a dataset containing more than 140 million third-party embeddings in over 41 million domains. To the best of our knowledge, this constitutes the largest web tracking dataset collected so far, and exceeds related studies by more than an order of magnitude in the number of domains and web pages analyzed. We perform a large-scale study of online tracking, on three levels: (1) On a global level, we give a precise figure for the extent of tracking, give insights into the structure of the `online tracking sphere' and analyse which trackers are used by how many websites. (2) On a country-specific level, we analyse which trackers are used by websites in different countries, and identify the countries in which websites choose significantly different trackers than in the rest of the world. (3) We answer the question whether the content of websites influences the choice of trackers they use, leveraging more than 90 thousand categorized domains. In particular, we analyse whether highly privacy-critical websites make different choices of trackers than other websites. Based on the performed analyses, we confirm that trackers are widespread (as expected), and that a small number of trackers dominates the web (Google, Facebook and Twitter). In particular, the three tracking domains with the highest PageRank are all owned by Google. The only exception to this pattern are a few countries such as China and Russia. Our results suggest that this dominance is strongly associated with country-specific political factors such as freedom of the press. We also confirm that websites with highly privacy-critical content are less likely to contain trackers (60% vs 90% for other websites), even though the majority of them still do contain trackers.
no_new_dataset
0.894052
1607.08414
Michael Wray
Michael Wray, Davide Moltisanti, Walterio Mayol-Cuevas and Dima Damen
SEMBED: Semantic Embedding of Egocentric Action Videos
null
null
null
null
cs.CV
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We present SEMBED, an approach for embedding an egocentric object interaction video in a semantic-visual graph to estimate the probability distribution over its potential semantic labels. When object interactions are annotated using unbounded choice of verbs, we embrace the wealth and ambiguity of these labels by capturing the semantic relationships as well as the visual similarities over motion and appearance features. We show how SEMBED can interpret a challenging dataset of 1225 freely annotated egocentric videos, outperforming SVM classification by more than 5%.
[ { "version": "v1", "created": "Thu, 28 Jul 2016 11:55:38 GMT" }, { "version": "v2", "created": "Fri, 29 Jul 2016 09:40:37 GMT" } ]
2016-08-01T00:00:00
[ [ "Wray", "Michael", "" ], [ "Moltisanti", "Davide", "" ], [ "Mayol-Cuevas", "Walterio", "" ], [ "Damen", "Dima", "" ] ]
TITLE: SEMBED: Semantic Embedding of Egocentric Action Videos ABSTRACT: We present SEMBED, an approach for embedding an egocentric object interaction video in a semantic-visual graph to estimate the probability distribution over its potential semantic labels. When object interactions are annotated using unbounded choice of verbs, we embrace the wealth and ambiguity of these labels by capturing the semantic relationships as well as the visual similarities over motion and appearance features. We show how SEMBED can interpret a challenging dataset of 1225 freely annotated egocentric videos, outperforming SVM classification by more than 5%.
no_new_dataset
0.937555
1607.08764
Ravi Kiran Sarvadevabhatla
Ravi Kiran Sarvadevabhatla, Shiv Surya, Srinivas S S Kruthiventi, Venkatesh Babu R
SwiDeN : Convolutional Neural Networks For Depiction Invariant Object Recognition
Accepted at ACMMM 2016. The first two authors contributed equally. Code and models at https://github.com/val-iisc/swiden
null
null
null
cs.CV
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Current state of the art object recognition architectures achieve impressive performance but are typically specialized for a single depictive style (e.g. photos only, sketches only). In this paper, we present SwiDeN : our Convolutional Neural Network (CNN) architecture which recognizes objects regardless of how they are visually depicted (line drawing, realistic shaded drawing, photograph etc.). In SwiDeN, we utilize a novel `deep' depictive style-based switching mechanism which appropriately addresses the depiction-specific and depiction-invariant aspects of the problem. We compare SwiDeN with alternative architectures and prior work on a 50-category Photo-Art dataset containing objects depicted in multiple styles. Experimental results show that SwiDeN outperforms other approaches for the depiction-invariant object recognition problem.
[ { "version": "v1", "created": "Fri, 29 Jul 2016 11:00:08 GMT" } ]
2016-08-01T00:00:00
[ [ "Sarvadevabhatla", "Ravi Kiran", "" ], [ "Surya", "Shiv", "" ], [ "Kruthiventi", "Srinivas S S", "" ], [ "R", "Venkatesh Babu", "" ] ]
TITLE: SwiDeN : Convolutional Neural Networks For Depiction Invariant Object Recognition ABSTRACT: Current state of the art object recognition architectures achieve impressive performance but are typically specialized for a single depictive style (e.g. photos only, sketches only). In this paper, we present SwiDeN : our Convolutional Neural Network (CNN) architecture which recognizes objects regardless of how they are visually depicted (line drawing, realistic shaded drawing, photograph etc.). In SwiDeN, we utilize a novel `deep' depictive style-based switching mechanism which appropriately addresses the depiction-specific and depiction-invariant aspects of the problem. We compare SwiDeN with alternative architectures and prior work on a 50-category Photo-Art dataset containing objects depicted in multiple styles. Experimental results show that SwiDeN outperforms other approaches for the depiction-invariant object recognition problem.
no_new_dataset
0.939913
1607.08807
Ingmar Weber
Palakorn Achananuparp and Ingmar Weber
Extracting Food Substitutes From Food Diary via Distributional Similarity
To appear at HealthRecSys'16
null
null
null
cs.CY cs.IR
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
In this paper, we explore the problem of identifying substitute relationship between food pairs from real-world food consumption data as the first step towards the healthier food recommendation. Our method is inspired by the distributional hypothesis in linguistics. Specifically, we assume that foods that are consumed in similar contexts are more likely to be similar dietarily. For example, a turkey sandwich can be considered a suitable substitute for a chicken sandwich if both tend to be consumed with french fries and salad. To evaluate our method, we constructed a real-world food consumption dataset from MyFitnessPal's public food diary entries and obtained ground-truth human judgements of food substitutes from a crowdsourcing service. The experiment results suggest the effectiveness of the method in identifying suitable substitutes.
[ { "version": "v1", "created": "Fri, 29 Jul 2016 13:46:17 GMT" } ]
2016-08-01T00:00:00
[ [ "Achananuparp", "Palakorn", "" ], [ "Weber", "Ingmar", "" ] ]
TITLE: Extracting Food Substitutes From Food Diary via Distributional Similarity ABSTRACT: In this paper, we explore the problem of identifying substitute relationship between food pairs from real-world food consumption data as the first step towards the healthier food recommendation. Our method is inspired by the distributional hypothesis in linguistics. Specifically, we assume that foods that are consumed in similar contexts are more likely to be similar dietarily. For example, a turkey sandwich can be considered a suitable substitute for a chicken sandwich if both tend to be consumed with french fries and salad. To evaluate our method, we constructed a real-world food consumption dataset from MyFitnessPal's public food diary entries and obtained ground-truth human judgements of food substitutes from a crowdsourcing service. The experiment results suggest the effectiveness of the method in identifying suitable substitutes.
new_dataset
0.647074
1607.08822
Peter Anderson
Peter Anderson, Basura Fernando, Mark Johnson, Stephen Gould
SPICE: Semantic Propositional Image Caption Evaluation
14 pages plus references, accepted to ECCV 2016
null
null
null
cs.CV cs.CL
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
There is considerable interest in the task of automatically generating image captions. However, evaluation is challenging. Existing automatic evaluation metrics are primarily sensitive to n-gram overlap, which is neither necessary nor sufficient for the task of simulating human judgment. We hypothesize that semantic propositional content is an important component of human caption evaluation, and propose a new automated caption evaluation metric defined over scene graphs coined SPICE. Extensive evaluations across a range of models and datasets indicate that SPICE captures human judgments over model-generated captions better than other automatic metrics (e.g., system-level correlation of 0.88 with human judgments on the MS COCO dataset, versus 0.43 for CIDEr and 0.53 for METEOR). Furthermore, SPICE can answer questions such as `which caption-generator best understands colors?' and `can caption-generators count?'
[ { "version": "v1", "created": "Fri, 29 Jul 2016 14:26:27 GMT" } ]
2016-08-01T00:00:00
[ [ "Anderson", "Peter", "" ], [ "Fernando", "Basura", "" ], [ "Johnson", "Mark", "" ], [ "Gould", "Stephen", "" ] ]
TITLE: SPICE: Semantic Propositional Image Caption Evaluation ABSTRACT: There is considerable interest in the task of automatically generating image captions. However, evaluation is challenging. Existing automatic evaluation metrics are primarily sensitive to n-gram overlap, which is neither necessary nor sufficient for the task of simulating human judgment. We hypothesize that semantic propositional content is an important component of human caption evaluation, and propose a new automated caption evaluation metric defined over scene graphs coined SPICE. Extensive evaluations across a range of models and datasets indicate that SPICE captures human judgments over model-generated captions better than other automatic metrics (e.g., system-level correlation of 0.88 with human judgments on the MS COCO dataset, versus 0.43 for CIDEr and 0.53 for METEOR). Furthermore, SPICE can answer questions such as `which caption-generator best understands colors?' and `can caption-generators count?'
no_new_dataset
0.923764
1506.08415
Andrea Burattin
Andrea Burattin
PLG2: Multiperspective Processes Randomization and Simulation for Online and Offline Settings
36 pages, minor updates
null
null
null
cs.SE
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Process mining represents an important field in BPM and data mining research. Recently, it has gained importance also for practitioners: more and more companies are creating business process intelligence solutions. The evaluation of process mining algorithms requires, as any other data mining task, the availability of large amount of real-world data. Despite the increasing availability of such datasets, they are affected by many limitations, in primis the absence of a "gold standard" (i.e., the reference model). This paper extends an approach, already available in the literature, for the generation of random processes. Novelties have been introduced throughout the work and, in particular, they involve the complete support for multiperspective models and logs (i.e., the control-flow perspective is enriched with time and data information) and for online settings (i.e., generation of multiperspective event streams and concept drifts). The proposed new framework is able to almost entirely cover the spectrum of possible scenarios that can be observed in the real-world. The proposed approach is implemented as a publicly available Java application, with a set of APIs for the programmatic execution of experiments.
[ { "version": "v1", "created": "Sun, 28 Jun 2015 15:28:24 GMT" }, { "version": "v2", "created": "Wed, 27 Jul 2016 09:15:43 GMT" }, { "version": "v3", "created": "Thu, 28 Jul 2016 05:51:01 GMT" } ]
2016-07-29T00:00:00
[ [ "Burattin", "Andrea", "" ] ]
TITLE: PLG2: Multiperspective Processes Randomization and Simulation for Online and Offline Settings ABSTRACT: Process mining represents an important field in BPM and data mining research. Recently, it has gained importance also for practitioners: more and more companies are creating business process intelligence solutions. The evaluation of process mining algorithms requires, as any other data mining task, the availability of large amount of real-world data. Despite the increasing availability of such datasets, they are affected by many limitations, in primis the absence of a "gold standard" (i.e., the reference model). This paper extends an approach, already available in the literature, for the generation of random processes. Novelties have been introduced throughout the work and, in particular, they involve the complete support for multiperspective models and logs (i.e., the control-flow perspective is enriched with time and data information) and for online settings (i.e., generation of multiperspective event streams and concept drifts). The proposed new framework is able to almost entirely cover the spectrum of possible scenarios that can be observed in the real-world. The proposed approach is implemented as a publicly available Java application, with a set of APIs for the programmatic execution of experiments.
no_new_dataset
0.939803
1604.00239
Piotr Koniusz
Piotr Koniusz and Anoop Cherian and Fatih Porikli
Tensor Representations via Kernel Linearization for Action Recognition from 3D Skeletons (Extended Version)
null
null
null
null
cs.CV
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
In this paper, we explore tensor representations that can compactly capture higher-order relationships between skeleton joints for 3D action recognition. We first define RBF kernels on 3D joint sequences, which are then linearized to form kernel descriptors. The higher-order outer-products of these kernel descriptors form our tensor representations. We present two different kernels for action recognition, namely (i) a sequence compatibility kernel that captures the spatio-temporal compatibility of joints in one sequence against those in the other, and (ii) a dynamics compatibility kernel that explicitly models the action dynamics of a sequence. Tensors formed from these kernels are then used to train an SVM. We present experiments on several benchmark datasets and demonstrate state of the art results, substantiating the effectiveness of our representations.
[ { "version": "v1", "created": "Fri, 1 Apr 2016 13:41:49 GMT" }, { "version": "v2", "created": "Thu, 28 Jul 2016 08:35:38 GMT" } ]
2016-07-29T00:00:00
[ [ "Koniusz", "Piotr", "" ], [ "Cherian", "Anoop", "" ], [ "Porikli", "Fatih", "" ] ]
TITLE: Tensor Representations via Kernel Linearization for Action Recognition from 3D Skeletons (Extended Version) ABSTRACT: In this paper, we explore tensor representations that can compactly capture higher-order relationships between skeleton joints for 3D action recognition. We first define RBF kernels on 3D joint sequences, which are then linearized to form kernel descriptors. The higher-order outer-products of these kernel descriptors form our tensor representations. We present two different kernels for action recognition, namely (i) a sequence compatibility kernel that captures the spatio-temporal compatibility of joints in one sequence against those in the other, and (ii) a dynamics compatibility kernel that explicitly models the action dynamics of a sequence. Tensors formed from these kernels are then used to train an SVM. We present experiments on several benchmark datasets and demonstrate state of the art results, substantiating the effectiveness of our representations.
no_new_dataset
0.95222
1604.01325
Albert Gordo
Albert Gordo, Jon Almazan, Jerome Revaud, Diane Larlus
Deep Image Retrieval: Learning global representations for image search
ECCV 2016 version + additional results
null
null
null
cs.CV
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We propose a novel approach for instance-level image retrieval. It produces a global and compact fixed-length representation for each image by aggregating many region-wise descriptors. In contrast to previous works employing pre-trained deep networks as a black box to produce features, our method leverages a deep architecture trained for the specific task of image retrieval. Our contribution is twofold: (i) we leverage a ranking framework to learn convolution and projection weights that are used to build the region features; and (ii) we employ a region proposal network to learn which regions should be pooled to form the final global descriptor. We show that using clean training data is key to the success of our approach. To that aim, we use a large scale but noisy landmark dataset and develop an automatic cleaning approach. The proposed architecture produces a global image representation in a single forward pass. Our approach significantly outperforms previous approaches based on global descriptors on standard datasets. It even surpasses most prior works based on costly local descriptor indexing and spatial verification. Additional material is available at www.xrce.xerox.com/Deep-Image-Retrieval.
[ { "version": "v1", "created": "Tue, 5 Apr 2016 16:48:17 GMT" }, { "version": "v2", "created": "Thu, 28 Jul 2016 10:44:17 GMT" } ]
2016-07-29T00:00:00
[ [ "Gordo", "Albert", "" ], [ "Almazan", "Jon", "" ], [ "Revaud", "Jerome", "" ], [ "Larlus", "Diane", "" ] ]
TITLE: Deep Image Retrieval: Learning global representations for image search ABSTRACT: We propose a novel approach for instance-level image retrieval. It produces a global and compact fixed-length representation for each image by aggregating many region-wise descriptors. In contrast to previous works employing pre-trained deep networks as a black box to produce features, our method leverages a deep architecture trained for the specific task of image retrieval. Our contribution is twofold: (i) we leverage a ranking framework to learn convolution and projection weights that are used to build the region features; and (ii) we employ a region proposal network to learn which regions should be pooled to form the final global descriptor. We show that using clean training data is key to the success of our approach. To that aim, we use a large scale but noisy landmark dataset and develop an automatic cleaning approach. The proposed architecture produces a global image representation in a single forward pass. Our approach significantly outperforms previous approaches based on global descriptors on standard datasets. It even surpasses most prior works based on costly local descriptor indexing and spatial verification. Additional material is available at www.xrce.xerox.com/Deep-Image-Retrieval.
no_new_dataset
0.948442
1604.04808
Arun Mallya
Arun Mallya and Svetlana Lazebnik
Learning Models for Actions and Person-Object Interactions with Transfer to Question Answering
null
null
null
null
cs.CV
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
This paper proposes deep convolutional network models that utilize local and global context to make human activity label predictions in still images, achieving state-of-the-art performance on two recent datasets with hundreds of labels each. We use multiple instance learning to handle the lack of supervision on the level of individual person instances, and weighted loss to handle unbalanced training data. Further, we show how specialized features trained on these datasets can be used to improve accuracy on the Visual Question Answering (VQA) task, in the form of multiple choice fill-in-the-blank questions (Visual Madlibs). Specifically, we tackle two types of questions on person activity and person-object relationship and show improvements over generic features trained on the ImageNet classification task.
[ { "version": "v1", "created": "Sat, 16 Apr 2016 22:54:05 GMT" }, { "version": "v2", "created": "Thu, 28 Jul 2016 04:44:36 GMT" } ]
2016-07-29T00:00:00
[ [ "Mallya", "Arun", "" ], [ "Lazebnik", "Svetlana", "" ] ]
TITLE: Learning Models for Actions and Person-Object Interactions with Transfer to Question Answering ABSTRACT: This paper proposes deep convolutional network models that utilize local and global context to make human activity label predictions in still images, achieving state-of-the-art performance on two recent datasets with hundreds of labels each. We use multiple instance learning to handle the lack of supervision on the level of individual person instances, and weighted loss to handle unbalanced training data. Further, we show how specialized features trained on these datasets can be used to improve accuracy on the Visual Question Answering (VQA) task, in the form of multiple choice fill-in-the-blank questions (Visual Madlibs). Specifically, we tackle two types of questions on person activity and person-object relationship and show improvements over generic features trained on the ImageNet classification task.
no_new_dataset
0.951142
1605.06155
Cheng Zhang
Cheng Zhang and Hedvig Kjellstrom and Carl Henrik Ek
Inter-Battery Topic Representation Learning
ECCV 2016
null
null
null
cs.LG cs.CV
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
In this paper, we present the Inter-Battery Topic Model (IBTM). Our approach extends traditional topic models by learning a factorized latent variable representation. The structured representation leads to a model that marries benefits traditionally associated with a discriminative approach, such as feature selection, with those of a generative model, such as principled regularization and ability to handle missing data. The factorization is provided by representing data in terms of aligned pairs of observations as different views. This provides means for selecting a representation that separately models topics that exist in both views from the topics that are unique to a single view. This structured consolidation allows for efficient and robust inference and provides a compact and efficient representation. Learning is performed in a Bayesian fashion by maximizing a rigorous bound on the log-likelihood. Firstly, we illustrate the benefits of the model on a synthetic dataset,. The model is then evaluated in both uni- and multi-modality settings on two different classification tasks with off-the-shelf convolutional neural network (CNN) features which generate state-of-the-art results with extremely compact representations.
[ { "version": "v1", "created": "Thu, 19 May 2016 21:44:12 GMT" }, { "version": "v2", "created": "Thu, 28 Jul 2016 10:08:40 GMT" } ]
2016-07-29T00:00:00
[ [ "Zhang", "Cheng", "" ], [ "Kjellstrom", "Hedvig", "" ], [ "Ek", "Carl Henrik", "" ] ]
TITLE: Inter-Battery Topic Representation Learning ABSTRACT: In this paper, we present the Inter-Battery Topic Model (IBTM). Our approach extends traditional topic models by learning a factorized latent variable representation. The structured representation leads to a model that marries benefits traditionally associated with a discriminative approach, such as feature selection, with those of a generative model, such as principled regularization and ability to handle missing data. The factorization is provided by representing data in terms of aligned pairs of observations as different views. This provides means for selecting a representation that separately models topics that exist in both views from the topics that are unique to a single view. This structured consolidation allows for efficient and robust inference and provides a compact and efficient representation. Learning is performed in a Bayesian fashion by maximizing a rigorous bound on the log-likelihood. Firstly, we illustrate the benefits of the model on a synthetic dataset,. The model is then evaluated in both uni- and multi-modality settings on two different classification tasks with off-the-shelf convolutional neural network (CNN) features which generate state-of-the-art results with extremely compact representations.
no_new_dataset
0.9455
1606.05002
Tanmay Gupta
Tanmay Gupta, Daeyun Shin, Naren Sivagnanadasan, Derek Hoiem
3DFS: Deformable Dense Depth Fusion and Segmentation for Object Reconstruction from a Handheld Camera
null
null
null
null
cs.CV
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We propose an approach for 3D reconstruction and segmentation of a single object placed on a flat surface from an input video. Our approach is to perform dense depth map estimation for multiple views using a proposed objective function that preserves detail. The resulting depth maps are then fused using a proposed implicit surface function that is robust to estimation error, producing a smooth surface reconstruction of the entire scene. Finally, the object is segmented from the remaining scene using a proposed 2D-3D segmentation that incorporates image and depth cues with priors and regularization over the 3D volume and 2D segmentations. We evaluate 3D reconstructions qualitatively on our Object-Videos dataset, comparing to fusion, multiview stereo, and segmentation baselines. We also quantitatively evaluate the dense depth estimation using the RGBD Scenes V2 dataset [Henry et al. 2013] and the segmentation using keyframe annotations of the Object-Videos dataset.
[ { "version": "v1", "created": "Wed, 15 Jun 2016 23:23:08 GMT" }, { "version": "v2", "created": "Wed, 27 Jul 2016 20:38:19 GMT" } ]
2016-07-29T00:00:00
[ [ "Gupta", "Tanmay", "" ], [ "Shin", "Daeyun", "" ], [ "Sivagnanadasan", "Naren", "" ], [ "Hoiem", "Derek", "" ] ]
TITLE: 3DFS: Deformable Dense Depth Fusion and Segmentation for Object Reconstruction from a Handheld Camera ABSTRACT: We propose an approach for 3D reconstruction and segmentation of a single object placed on a flat surface from an input video. Our approach is to perform dense depth map estimation for multiple views using a proposed objective function that preserves detail. The resulting depth maps are then fused using a proposed implicit surface function that is robust to estimation error, producing a smooth surface reconstruction of the entire scene. Finally, the object is segmented from the remaining scene using a proposed 2D-3D segmentation that incorporates image and depth cues with priors and regularization over the 3D volume and 2D segmentations. We evaluate 3D reconstructions qualitatively on our Object-Videos dataset, comparing to fusion, multiview stereo, and segmentation baselines. We also quantitatively evaluate the dense depth estimation using the RGBD Scenes V2 dataset [Henry et al. 2013] and the segmentation using keyframe annotations of the Object-Videos dataset.
no_new_dataset
0.918772
1607.08381
Rahul Rama Varior Mr.
Rahul Rama Varior, Bing Shuai, Jiwen Lu, Dong Xu, and Gang Wang
A Siamese Long Short-Term Memory Architecture for Human Re-Identification
null
null
null
null
cs.CV
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Matching pedestrians across multiple camera views known as human re-identification (re-identification) is a challenging problem in visual surveillance. In the existing works concentrating on feature extraction, representations are formed locally and independent of other regions. We present a novel siamese Long Short-Term Memory (LSTM) architecture that can process image regions sequentially and enhance the discriminative capability of local feature representation by leveraging contextual information. The feedback connections and internal gating mechanism of the LSTM cells enable our model to memorize the spatial dependencies and selectively propagate relevant contextual information through the network. We demonstrate improved performance compared to the baseline algorithm with no LSTM units and promising results compared to state-of-the-art methods on Market-1501, CUHK03 and VIPeR datasets. Visualization of the internal mechanism of LSTM cells shows meaningful patterns can be learned by our method.
[ { "version": "v1", "created": "Thu, 28 Jul 2016 09:43:52 GMT" } ]
2016-07-29T00:00:00
[ [ "Varior", "Rahul Rama", "" ], [ "Shuai", "Bing", "" ], [ "Lu", "Jiwen", "" ], [ "Xu", "Dong", "" ], [ "Wang", "Gang", "" ] ]
TITLE: A Siamese Long Short-Term Memory Architecture for Human Re-Identification ABSTRACT: Matching pedestrians across multiple camera views known as human re-identification (re-identification) is a challenging problem in visual surveillance. In the existing works concentrating on feature extraction, representations are formed locally and independent of other regions. We present a novel siamese Long Short-Term Memory (LSTM) architecture that can process image regions sequentially and enhance the discriminative capability of local feature representation by leveraging contextual information. The feedback connections and internal gating mechanism of the LSTM cells enable our model to memorize the spatial dependencies and selectively propagate relevant contextual information through the network. We demonstrate improved performance compared to the baseline algorithm with no LSTM units and promising results compared to state-of-the-art methods on Market-1501, CUHK03 and VIPeR datasets. Visualization of the internal mechanism of LSTM cells shows meaningful patterns can be learned by our method.
no_new_dataset
0.9455