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1603.09188
Spandana Gella
Spandana Gella, Mirella Lapata, Frank Keller
Unsupervised Visual Sense Disambiguation for Verbs using Multimodal Embeddings
11 pages, NAACL-HLT 2016
null
null
null
cs.CL cs.CV
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We introduce a new task, visual sense disambiguation for verbs: given an image and a verb, assign the correct sense of the verb, i.e., the one that describes the action depicted in the image. Just as textual word sense disambiguation is useful for a wide range of NLP tasks, visual sense disambiguation can be useful for multimodal tasks such as image retrieval, image description, and text illustration. We introduce VerSe, a new dataset that augments existing multimodal datasets (COCO and TUHOI) with sense labels. We propose an unsupervised algorithm based on Lesk which performs visual sense disambiguation using textual, visual, or multimodal embeddings. We find that textual embeddings perform well when gold-standard textual annotations (object labels and image descriptions) are available, while multimodal embeddings perform well on unannotated images. We also verify our findings by using the textual and multimodal embeddings as features in a supervised setting and analyse the performance of visual sense disambiguation task. VerSe is made publicly available and can be downloaded at: https://github.com/spandanagella/verse.
[ { "version": "v1", "created": "Wed, 30 Mar 2016 13:43:38 GMT" } ]
2016-03-31T00:00:00
[ [ "Gella", "Spandana", "" ], [ "Lapata", "Mirella", "" ], [ "Keller", "Frank", "" ] ]
TITLE: Unsupervised Visual Sense Disambiguation for Verbs using Multimodal Embeddings ABSTRACT: We introduce a new task, visual sense disambiguation for verbs: given an image and a verb, assign the correct sense of the verb, i.e., the one that describes the action depicted in the image. Just as textual word sense disambiguation is useful for a wide range of NLP tasks, visual sense disambiguation can be useful for multimodal tasks such as image retrieval, image description, and text illustration. We introduce VerSe, a new dataset that augments existing multimodal datasets (COCO and TUHOI) with sense labels. We propose an unsupervised algorithm based on Lesk which performs visual sense disambiguation using textual, visual, or multimodal embeddings. We find that textual embeddings perform well when gold-standard textual annotations (object labels and image descriptions) are available, while multimodal embeddings perform well on unannotated images. We also verify our findings by using the textual and multimodal embeddings as features in a supervised setting and analyse the performance of visual sense disambiguation task. VerSe is made publicly available and can be downloaded at: https://github.com/spandanagella/verse.
new_dataset
0.960547
1409.4327
Dinesh Jayaraman
Dinesh Jayaraman and Kristen Grauman
Zero Shot Recognition with Unreliable Attributes
NIPS 2014
null
null
null
cs.CV stat.ML
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
In principle, zero-shot learning makes it possible to train a recognition model simply by specifying the category's attributes. For example, with classifiers for generic attributes like \emph{striped} and \emph{four-legged}, one can construct a classifier for the zebra category by enumerating which properties it possesses---even without providing zebra training images. In practice, however, the standard zero-shot paradigm suffers because attribute predictions in novel images are hard to get right. We propose a novel random forest approach to train zero-shot models that explicitly accounts for the unreliability of attribute predictions. By leveraging statistics about each attribute's error tendencies, our method obtains more robust discriminative models for the unseen classes. We further devise extensions to handle the few-shot scenario and unreliable attribute descriptions. On three datasets, we demonstrate the benefit for visual category learning with zero or few training examples, a critical domain for rare categories or categories defined on the fly.
[ { "version": "v1", "created": "Mon, 15 Sep 2014 16:56:07 GMT" }, { "version": "v2", "created": "Tue, 29 Mar 2016 19:33:17 GMT" } ]
2016-03-30T00:00:00
[ [ "Jayaraman", "Dinesh", "" ], [ "Grauman", "Kristen", "" ] ]
TITLE: Zero Shot Recognition with Unreliable Attributes ABSTRACT: In principle, zero-shot learning makes it possible to train a recognition model simply by specifying the category's attributes. For example, with classifiers for generic attributes like \emph{striped} and \emph{four-legged}, one can construct a classifier for the zebra category by enumerating which properties it possesses---even without providing zebra training images. In practice, however, the standard zero-shot paradigm suffers because attribute predictions in novel images are hard to get right. We propose a novel random forest approach to train zero-shot models that explicitly accounts for the unreliability of attribute predictions. By leveraging statistics about each attribute's error tendencies, our method obtains more robust discriminative models for the unseen classes. We further devise extensions to handle the few-shot scenario and unreliable attribute descriptions. On three datasets, we demonstrate the benefit for visual category learning with zero or few training examples, a critical domain for rare categories or categories defined on the fly.
no_new_dataset
0.947332
1505.02206
Dinesh Jayaraman
Dinesh Jayaraman and Kristen Grauman
Learning image representations tied to ego-motion
Supplementary material appended at end. In ICCV 2015
null
null
null
cs.CV cs.AI stat.ML
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Understanding how images of objects and scenes behave in response to specific ego-motions is a crucial aspect of proper visual development, yet existing visual learning methods are conspicuously disconnected from the physical source of their images. We propose to exploit proprioceptive motor signals to provide unsupervised regularization in convolutional neural networks to learn visual representations from egocentric video. Specifically, we enforce that our learned features exhibit equivariance i.e. they respond predictably to transformations associated with distinct ego-motions. With three datasets, we show that our unsupervised feature learning approach significantly outperforms previous approaches on visual recognition and next-best-view prediction tasks. In the most challenging test, we show that features learned from video captured on an autonomous driving platform improve large-scale scene recognition in static images from a disjoint domain.
[ { "version": "v1", "created": "Fri, 8 May 2015 23:15:00 GMT" }, { "version": "v2", "created": "Tue, 29 Mar 2016 19:30:18 GMT" } ]
2016-03-30T00:00:00
[ [ "Jayaraman", "Dinesh", "" ], [ "Grauman", "Kristen", "" ] ]
TITLE: Learning image representations tied to ego-motion ABSTRACT: Understanding how images of objects and scenes behave in response to specific ego-motions is a crucial aspect of proper visual development, yet existing visual learning methods are conspicuously disconnected from the physical source of their images. We propose to exploit proprioceptive motor signals to provide unsupervised regularization in convolutional neural networks to learn visual representations from egocentric video. Specifically, we enforce that our learned features exhibit equivariance i.e. they respond predictably to transformations associated with distinct ego-motions. With three datasets, we show that our unsupervised feature learning approach significantly outperforms previous approaches on visual recognition and next-best-view prediction tasks. In the most challenging test, we show that features learned from video captured on an autonomous driving platform improve large-scale scene recognition in static images from a disjoint domain.
no_new_dataset
0.946399
1511.06881
Fangting Xia
Fangting Xia, Peng Wang, Liang-Chieh Chen, Alan L. Yuille
Zoom Better to See Clearer: Human and Object Parsing with Hierarchical Auto-Zoom Net
A shortened version has been submitted to ECCV 2016
null
null
null
cs.CV cs.LG
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Parsing articulated objects, e.g. humans and animals, into semantic parts (e.g. body, head and arms, etc.) from natural images is a challenging and fundamental problem for computer vision. A big difficulty is the large variability of scale and location for objects and their corresponding parts. Even limited mistakes in estimating scale and location will degrade the parsing output and cause errors in boundary details. To tackle these difficulties, we propose a "Hierarchical Auto-Zoom Net" (HAZN) for object part parsing which adapts to the local scales of objects and parts. HAZN is a sequence of two "Auto-Zoom Net" (AZNs), each employing fully convolutional networks that perform two tasks: (1) predict the locations and scales of object instances (the first AZN) or their parts (the second AZN); (2) estimate the part scores for predicted object instance or part regions. Our model can adaptively "zoom" (resize) predicted image regions into their proper scales to refine the parsing. We conduct extensive experiments over the PASCAL part datasets on humans, horses, and cows. For humans, our approach significantly outperforms the state-of-the-arts by 5% mIOU and is especially better at segmenting small instances and small parts. We obtain similar improvements for parsing cows and horses over alternative methods. In summary, our strategy of first zooming into objects and then zooming into parts is very effective. It also enables us to process different regions of the image at different scales adaptively so that, for example, we do not need to waste computational resources scaling the entire image.
[ { "version": "v1", "created": "Sat, 21 Nov 2015 13:32:26 GMT" }, { "version": "v2", "created": "Wed, 25 Nov 2015 00:39:14 GMT" }, { "version": "v3", "created": "Mon, 30 Nov 2015 02:32:33 GMT" }, { "version": "v4", "created": "Thu, 7 Jan 2016 23:48:34 GMT" }, { "version": "v5", "created": "Mon, 28 Mar 2016 21:53:31 GMT" } ]
2016-03-30T00:00:00
[ [ "Xia", "Fangting", "" ], [ "Wang", "Peng", "" ], [ "Chen", "Liang-Chieh", "" ], [ "Yuille", "Alan L.", "" ] ]
TITLE: Zoom Better to See Clearer: Human and Object Parsing with Hierarchical Auto-Zoom Net ABSTRACT: Parsing articulated objects, e.g. humans and animals, into semantic parts (e.g. body, head and arms, etc.) from natural images is a challenging and fundamental problem for computer vision. A big difficulty is the large variability of scale and location for objects and their corresponding parts. Even limited mistakes in estimating scale and location will degrade the parsing output and cause errors in boundary details. To tackle these difficulties, we propose a "Hierarchical Auto-Zoom Net" (HAZN) for object part parsing which adapts to the local scales of objects and parts. HAZN is a sequence of two "Auto-Zoom Net" (AZNs), each employing fully convolutional networks that perform two tasks: (1) predict the locations and scales of object instances (the first AZN) or their parts (the second AZN); (2) estimate the part scores for predicted object instance or part regions. Our model can adaptively "zoom" (resize) predicted image regions into their proper scales to refine the parsing. We conduct extensive experiments over the PASCAL part datasets on humans, horses, and cows. For humans, our approach significantly outperforms the state-of-the-arts by 5% mIOU and is especially better at segmenting small instances and small parts. We obtain similar improvements for parsing cows and horses over alternative methods. In summary, our strategy of first zooming into objects and then zooming into parts is very effective. It also enables us to process different regions of the image at different scales adaptively so that, for example, we do not need to waste computational resources scaling the entire image.
no_new_dataset
0.949716
1511.08418
Maria Oliver
Maria Oliver, Gloria Haro, Mariella Dimiccoli, Baptiste Mazin and Coloma Ballester
A Computational Model for Amodal Completion
null
null
10.1007/s10851-016-0652-x
null
cs.CV
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
This paper presents a computational model to recover the most likely interpretation of the 3D scene structure from a planar image, where some objects may occlude others. The estimated scene interpretation is obtained by integrating some global and local cues and provides both the complete disoccluded objects that form the scene and their ordering according to depth. Our method first computes several distal scenes which are compatible with the proximal planar image. To compute these different hypothesized scenes, we propose a perceptually inspired object disocclusion method, which works by minimizing the Euler's elastica as well as by incorporating the relatability of partially occluded contours and the convexity of the disoccluded objects. Then, to estimate the preferred scene we rely on a Bayesian model and define probabilities taking into account the global complexity of the objects in the hypothesized scenes as well as the effort of bringing these objects in their relative position in the planar image, which is also measured by an Euler's elastica-based quantity. The model is illustrated with numerical experiments on, both, synthetic and real images showing the ability of our model to reconstruct the occluded objects and the preferred perceptual order among them. We also present results on images of the Berkeley dataset with provided figure-ground ground-truth labeling.
[ { "version": "v1", "created": "Thu, 26 Nov 2015 15:25:46 GMT" }, { "version": "v2", "created": "Tue, 29 Mar 2016 14:49:41 GMT" } ]
2016-03-30T00:00:00
[ [ "Oliver", "Maria", "" ], [ "Haro", "Gloria", "" ], [ "Dimiccoli", "Mariella", "" ], [ "Mazin", "Baptiste", "" ], [ "Ballester", "Coloma", "" ] ]
TITLE: A Computational Model for Amodal Completion ABSTRACT: This paper presents a computational model to recover the most likely interpretation of the 3D scene structure from a planar image, where some objects may occlude others. The estimated scene interpretation is obtained by integrating some global and local cues and provides both the complete disoccluded objects that form the scene and their ordering according to depth. Our method first computes several distal scenes which are compatible with the proximal planar image. To compute these different hypothesized scenes, we propose a perceptually inspired object disocclusion method, which works by minimizing the Euler's elastica as well as by incorporating the relatability of partially occluded contours and the convexity of the disoccluded objects. Then, to estimate the preferred scene we rely on a Bayesian model and define probabilities taking into account the global complexity of the objects in the hypothesized scenes as well as the effort of bringing these objects in their relative position in the planar image, which is also measured by an Euler's elastica-based quantity. The model is illustrated with numerical experiments on, both, synthetic and real images showing the ability of our model to reconstruct the occluded objects and the preferred perceptual order among them. We also present results on images of the Berkeley dataset with provided figure-ground ground-truth labeling.
no_new_dataset
0.949482
1512.06395
Jaroslaw Szlichta
Mehdi Kargar, Lukasz Golab, Jaroslaw Szlichta
Effective Keyword Search in Graphs
7 pages, 9 figures
null
null
null
cs.DB
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
In a node-labeled graph, keyword search finds subtrees of the graph whose nodes contain all of the query keywords. This provides a way to query graph databases that neither requires mastery of a query language such as SPARQL, nor a deep knowledge of the database schema. Previous work ranks answer trees using combinations of structural and content-based metrics, such as path lengths between keywords or relevance of the labels in the answer tree to the query keywords. We propose two new ways to rank keyword search results over graphs. The first takes node importance into account while the second is a bi-objective optimization of edge weights and node importance. Since both of these problems are NP-hard, we propose greedy algorithms to solve them, and experimentally verify their effectiveness and efficiency on a real dataset.
[ { "version": "v1", "created": "Sun, 20 Dec 2015 16:20:17 GMT" }, { "version": "v2", "created": "Tue, 19 Jan 2016 16:59:38 GMT" }, { "version": "v3", "created": "Wed, 3 Feb 2016 19:14:03 GMT" }, { "version": "v4", "created": "Wed, 23 Mar 2016 19:54:12 GMT" }, { "version": "v5", "created": "Tue, 29 Mar 2016 15:43:11 GMT" } ]
2016-03-30T00:00:00
[ [ "Kargar", "Mehdi", "" ], [ "Golab", "Lukasz", "" ], [ "Szlichta", "Jaroslaw", "" ] ]
TITLE: Effective Keyword Search in Graphs ABSTRACT: In a node-labeled graph, keyword search finds subtrees of the graph whose nodes contain all of the query keywords. This provides a way to query graph databases that neither requires mastery of a query language such as SPARQL, nor a deep knowledge of the database schema. Previous work ranks answer trees using combinations of structural and content-based metrics, such as path lengths between keywords or relevance of the labels in the answer tree to the query keywords. We propose two new ways to rank keyword search results over graphs. The first takes node importance into account while the second is a bi-objective optimization of edge weights and node importance. Since both of these problems are NP-hard, we propose greedy algorithms to solve them, and experimentally verify their effectiveness and efficiency on a real dataset.
no_new_dataset
0.951233
1602.05388
Muhammad Imran
Muhammad Imran, Prasenjit Mitra, Jaideep Srivastava
Cross-Language Domain Adaptation for Classifying Crisis-Related Short Messages
ISCRAM 2016, 10 pages, 4 tables
null
null
null
cs.CL
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Rapid crisis response requires real-time analysis of messages. After a disaster happens, volunteers attempt to classify tweets to determine needs, e.g., supplies, infrastructure damage, etc. Given labeled data, supervised machine learning can help classify these messages. Scarcity of labeled data causes poor performance in machine training. Can we reuse old tweets to train classifiers? How can we choose labeled tweets for training? Specifically, we study the usefulness of labeled data of past events. Do labeled tweets in different language help? We observe the performance of our classifiers trained using different combinations of training sets obtained from past disasters. We perform extensive experimentation on real crisis datasets and show that the past labels are useful when both source and target events are of the same type (e.g. both earthquakes). For similar languages (e.g., Italian and Spanish), cross-language domain adaptation was useful, however, when for different languages (e.g., Italian and English), the performance decreased.
[ { "version": "v1", "created": "Wed, 17 Feb 2016 12:29:56 GMT" }, { "version": "v2", "created": "Tue, 29 Mar 2016 07:18:43 GMT" } ]
2016-03-30T00:00:00
[ [ "Imran", "Muhammad", "" ], [ "Mitra", "Prasenjit", "" ], [ "Srivastava", "Jaideep", "" ] ]
TITLE: Cross-Language Domain Adaptation for Classifying Crisis-Related Short Messages ABSTRACT: Rapid crisis response requires real-time analysis of messages. After a disaster happens, volunteers attempt to classify tweets to determine needs, e.g., supplies, infrastructure damage, etc. Given labeled data, supervised machine learning can help classify these messages. Scarcity of labeled data causes poor performance in machine training. Can we reuse old tweets to train classifiers? How can we choose labeled tweets for training? Specifically, we study the usefulness of labeled data of past events. Do labeled tweets in different language help? We observe the performance of our classifiers trained using different combinations of training sets obtained from past disasters. We perform extensive experimentation on real crisis datasets and show that the past labels are useful when both source and target events are of the same type (e.g. both earthquakes). For similar languages (e.g., Italian and Spanish), cross-language domain adaptation was useful, however, when for different languages (e.g., Italian and English), the performance decreased.
no_new_dataset
0.949949
1603.01774
Behnam Ghavimi
Behnam Ghavimi (1,2), Philipp Mayr (1), Sahar Vahdati (2) and Christoph Lange (2,3) ((1) GESIS Leibniz Institute for the Social Sciences, (2) University of Bonn, (3) Fraunhofer IAIS)
Identifying and Improving Dataset References in Social Sciences Full Texts
null
null
null
null
cs.DL cs.IR
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Scientific full text papers are usually stored in separate places than their underlying research datasets. Authors typically make references to datasets by mentioning them for example by using their titles and the year of publication. However, in most cases explicit links that would provide readers with direct access to referenced datasets are missing. Manually detecting references to datasets in papers is time consuming and requires an expert in the domain of the paper. In order to make explicit all links to datasets in papers that have been published already, we suggest and evaluate a semi-automatic approach for finding references to datasets in social sciences papers. Our approach does not need a corpus of papers (no cold start problem) and it performs well on a small test corpus (gold standard). Our approach achieved an F-measure of 0.84 for identifying references in full texts and an F-measure of 0.83 for finding correct matches of detected references in the da|ra dataset registry.
[ { "version": "v1", "created": "Sun, 6 Mar 2016 01:09:08 GMT" }, { "version": "v2", "created": "Tue, 29 Mar 2016 12:36:27 GMT" } ]
2016-03-30T00:00:00
[ [ "Ghavimi", "Behnam", "" ], [ "Mayr", "Philipp", "" ], [ "Vahdati", "Sahar", "" ], [ "Lange", "Christoph", "" ] ]
TITLE: Identifying and Improving Dataset References in Social Sciences Full Texts ABSTRACT: Scientific full text papers are usually stored in separate places than their underlying research datasets. Authors typically make references to datasets by mentioning them for example by using their titles and the year of publication. However, in most cases explicit links that would provide readers with direct access to referenced datasets are missing. Manually detecting references to datasets in papers is time consuming and requires an expert in the domain of the paper. In order to make explicit all links to datasets in papers that have been published already, we suggest and evaluate a semi-automatic approach for finding references to datasets in social sciences papers. Our approach does not need a corpus of papers (no cold start problem) and it performs well on a small test corpus (gold standard). Our approach achieved an F-measure of 0.84 for identifying references in full texts and an F-measure of 0.83 for finding correct matches of detected references in the da|ra dataset registry.
no_new_dataset
0.943504
1603.08701
Enrico Santus
Enrico Santus, Tin-Shing Chiu, Qin Lu, Alessandro Lenci, Chu-Ren Huang
What a Nerd! Beating Students and Vector Cosine in the ESL and TOEFL Datasets
in LREC 2016
null
null
null
cs.CL
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
In this paper, we claim that Vector Cosine, which is generally considered one of the most efficient unsupervised measures for identifying word similarity in Vector Space Models, can be outperformed by a completely unsupervised measure that evaluates the extent of the intersection among the most associated contexts of two target words, weighting such intersection according to the rank of the shared contexts in the dependency ranked lists. This claim comes from the hypothesis that similar words do not simply occur in similar contexts, but they share a larger portion of their most relevant contexts compared to other related words. To prove it, we describe and evaluate APSyn, a variant of Average Precision that, independently of the adopted parameters, outperforms the Vector Cosine and the co-occurrence on the ESL and TOEFL test sets. In the best setting, APSyn reaches 0.73 accuracy on the ESL dataset and 0.70 accuracy in the TOEFL dataset, beating therefore the non-English US college applicants (whose average, as reported in the literature, is 64.50%) and several state-of-the-art approaches.
[ { "version": "v1", "created": "Tue, 29 Mar 2016 10:00:27 GMT" } ]
2016-03-30T00:00:00
[ [ "Santus", "Enrico", "" ], [ "Chiu", "Tin-Shing", "" ], [ "Lu", "Qin", "" ], [ "Lenci", "Alessandro", "" ], [ "Huang", "Chu-Ren", "" ] ]
TITLE: What a Nerd! Beating Students and Vector Cosine in the ESL and TOEFL Datasets ABSTRACT: In this paper, we claim that Vector Cosine, which is generally considered one of the most efficient unsupervised measures for identifying word similarity in Vector Space Models, can be outperformed by a completely unsupervised measure that evaluates the extent of the intersection among the most associated contexts of two target words, weighting such intersection according to the rank of the shared contexts in the dependency ranked lists. This claim comes from the hypothesis that similar words do not simply occur in similar contexts, but they share a larger portion of their most relevant contexts compared to other related words. To prove it, we describe and evaluate APSyn, a variant of Average Precision that, independently of the adopted parameters, outperforms the Vector Cosine and the co-occurrence on the ESL and TOEFL test sets. In the best setting, APSyn reaches 0.73 accuracy on the ESL dataset and 0.70 accuracy in the TOEFL dataset, beating therefore the non-English US college applicants (whose average, as reported in the literature, is 64.50%) and several state-of-the-art approaches.
no_new_dataset
0.944791
1603.08702
Enrico Santus
Enrico Santus, Alessandro Lenci, Tin-Shing Chiu, Qin Lu, Chu-Ren Huang
Nine Features in a Random Forest to Learn Taxonomical Semantic Relations
in LREC 2016
null
null
null
cs.CL
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
ROOT9 is a supervised system for the classification of hypernyms, co-hyponyms and random words that is derived from the already introduced ROOT13 (Santus et al., 2016). It relies on a Random Forest algorithm and nine unsupervised corpus-based features. We evaluate it with a 10-fold cross validation on 9,600 pairs, equally distributed among the three classes and involving several Parts-Of-Speech (i.e. adjectives, nouns and verbs). When all the classes are present, ROOT9 achieves an F1 score of 90.7%, against a baseline of 57.2% (vector cosine). When the classification is binary, ROOT9 achieves the following results against the baseline: hypernyms-co-hyponyms 95.7% vs. 69.8%, hypernyms-random 91.8% vs. 64.1% and co-hyponyms-random 97.8% vs. 79.4%. In order to compare the performance with the state-of-the-art, we have also evaluated ROOT9 in subsets of the Weeds et al. (2014) datasets, proving that it is in fact competitive. Finally, we investigated whether the system learns the semantic relation or it simply learns the prototypical hypernyms, as claimed by Levy et al. (2015). The second possibility seems to be the most likely, even though ROOT9 can be trained on negative examples (i.e., switched hypernyms) to drastically reduce this bias.
[ { "version": "v1", "created": "Tue, 29 Mar 2016 10:00:40 GMT" } ]
2016-03-30T00:00:00
[ [ "Santus", "Enrico", "" ], [ "Lenci", "Alessandro", "" ], [ "Chiu", "Tin-Shing", "" ], [ "Lu", "Qin", "" ], [ "Huang", "Chu-Ren", "" ] ]
TITLE: Nine Features in a Random Forest to Learn Taxonomical Semantic Relations ABSTRACT: ROOT9 is a supervised system for the classification of hypernyms, co-hyponyms and random words that is derived from the already introduced ROOT13 (Santus et al., 2016). It relies on a Random Forest algorithm and nine unsupervised corpus-based features. We evaluate it with a 10-fold cross validation on 9,600 pairs, equally distributed among the three classes and involving several Parts-Of-Speech (i.e. adjectives, nouns and verbs). When all the classes are present, ROOT9 achieves an F1 score of 90.7%, against a baseline of 57.2% (vector cosine). When the classification is binary, ROOT9 achieves the following results against the baseline: hypernyms-co-hyponyms 95.7% vs. 69.8%, hypernyms-random 91.8% vs. 64.1% and co-hyponyms-random 97.8% vs. 79.4%. In order to compare the performance with the state-of-the-art, we have also evaluated ROOT9 in subsets of the Weeds et al. (2014) datasets, proving that it is in fact competitive. Finally, we investigated whether the system learns the semantic relation or it simply learns the prototypical hypernyms, as claimed by Levy et al. (2015). The second possibility seems to be the most likely, even though ROOT9 can be trained on negative examples (i.e., switched hypernyms) to drastically reduce this bias.
no_new_dataset
0.95469
1603.08767
Daniel Pop
Daniel Pop
Machine Learning and Cloud Computing: Survey of Distributed and SaaS Solutions
This manuscript was originally published as IEAT Technical Report at https://www.ieat.ro/technical-reports in 2012
null
null
IEAT-TR-2012-1
cs.DC cs.LG
http://creativecommons.org/licenses/by-nc-sa/4.0/
Applying popular machine learning algorithms to large amounts of data raised new challenges for the ML practitioners. Traditional ML libraries does not support well processing of huge datasets, so that new approaches were needed. Parallelization using modern parallel computing frameworks, such as MapReduce, CUDA, or Dryad gained in popularity and acceptance, resulting in new ML libraries developed on top of these frameworks. We will briefly introduce the most prominent industrial and academic outcomes, such as Apache Mahout, GraphLab or Jubatus. We will investigate how cloud computing paradigm impacted the field of ML. First direction is of popular statistics tools and libraries (R system, Python) deployed in the cloud. A second line of products is augmenting existing tools with plugins that allow users to create a Hadoop cluster in the cloud and run jobs on it. Next on the list are libraries of distributed implementations for ML algorithms, and on-premise deployments of complex systems for data analytics and data mining. Last approach on the radar of this survey is ML as Software-as-a-Service, several BigData start-ups (and large companies as well) already opening their solutions to the market.
[ { "version": "v1", "created": "Tue, 29 Mar 2016 13:29:35 GMT" } ]
2016-03-30T00:00:00
[ [ "Pop", "Daniel", "" ] ]
TITLE: Machine Learning and Cloud Computing: Survey of Distributed and SaaS Solutions ABSTRACT: Applying popular machine learning algorithms to large amounts of data raised new challenges for the ML practitioners. Traditional ML libraries does not support well processing of huge datasets, so that new approaches were needed. Parallelization using modern parallel computing frameworks, such as MapReduce, CUDA, or Dryad gained in popularity and acceptance, resulting in new ML libraries developed on top of these frameworks. We will briefly introduce the most prominent industrial and academic outcomes, such as Apache Mahout, GraphLab or Jubatus. We will investigate how cloud computing paradigm impacted the field of ML. First direction is of popular statistics tools and libraries (R system, Python) deployed in the cloud. A second line of products is augmenting existing tools with plugins that allow users to create a Hadoop cluster in the cloud and run jobs on it. Next on the list are libraries of distributed implementations for ML algorithms, and on-premise deployments of complex systems for data analytics and data mining. Last approach on the radar of this survey is ML as Software-as-a-Service, several BigData start-ups (and large companies as well) already opening their solutions to the market.
no_new_dataset
0.941223
1603.08869
Tiancheng Zhao
Tiancheng Zhao, Mohammad Gowayyed
Algorithms for Batch Hierarchical Reinforcement Learning
null
null
null
null
cs.AI
http://creativecommons.org/licenses/by/4.0/
Hierarchical Reinforcement Learning (HRL) exploits temporal abstraction to solve large Markov Decision Processes (MDP) and provide transferable subtask policies. In this paper, we introduce an off-policy HRL algorithm: Hierarchical Q-value Iteration (HQI). We show that it is possible to effectively learn recursive optimal policies for any valid hierarchical decomposition of the original MDP, given a fixed dataset collected from a flat stochastic behavioral policy. We first formally prove the convergence of the algorithm for tabular MDP. Then our experiments on the Taxi domain show that HQI converges faster than a flat Q-value Iteration and enjoys easy state abstraction. Also, we demonstrate that our algorithm is able to learn optimal policies for different hierarchical structures from the same fixed dataset, which enables model comparison without recollecting data.
[ { "version": "v1", "created": "Tue, 29 Mar 2016 18:17:17 GMT" } ]
2016-03-30T00:00:00
[ [ "Zhao", "Tiancheng", "" ], [ "Gowayyed", "Mohammad", "" ] ]
TITLE: Algorithms for Batch Hierarchical Reinforcement Learning ABSTRACT: Hierarchical Reinforcement Learning (HRL) exploits temporal abstraction to solve large Markov Decision Processes (MDP) and provide transferable subtask policies. In this paper, we introduce an off-policy HRL algorithm: Hierarchical Q-value Iteration (HQI). We show that it is possible to effectively learn recursive optimal policies for any valid hierarchical decomposition of the original MDP, given a fixed dataset collected from a flat stochastic behavioral policy. We first formally prove the convergence of the algorithm for tabular MDP. Then our experiments on the Taxi domain show that HQI converges faster than a flat Q-value Iteration and enjoys easy state abstraction. Also, we demonstrate that our algorithm is able to learn optimal policies for different hierarchical structures from the same fixed dataset, which enables model comparison without recollecting data.
no_new_dataset
0.942876
1603.08884
Adam Trischler
Adam Trischler and Zheng Ye and Xingdi Yuan and Jing He and Phillip Bachman and Kaheer Suleman
A Parallel-Hierarchical Model for Machine Comprehension on Sparse Data
9 pages, submitted to ACL
null
null
null
cs.CL
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Understanding unstructured text is a major goal within natural language processing. Comprehension tests pose questions based on short text passages to evaluate such understanding. In this work, we investigate machine comprehension on the challenging {\it MCTest} benchmark. Partly because of its limited size, prior work on {\it MCTest} has focused mainly on engineering better features. We tackle the dataset with a neural approach, harnessing simple neural networks arranged in a parallel hierarchy. The parallel hierarchy enables our model to compare the passage, question, and answer from a variety of trainable perspectives, as opposed to using a manually designed, rigid feature set. Perspectives range from the word level to sentence fragments to sequences of sentences; the networks operate only on word-embedding representations of text. When trained with a methodology designed to help cope with limited training data, our Parallel-Hierarchical model sets a new state of the art for {\it MCTest}, outperforming previous feature-engineered approaches slightly and previous neural approaches by a significant margin (over 15\% absolute).
[ { "version": "v1", "created": "Tue, 29 Mar 2016 18:52:46 GMT" } ]
2016-03-30T00:00:00
[ [ "Trischler", "Adam", "" ], [ "Ye", "Zheng", "" ], [ "Yuan", "Xingdi", "" ], [ "He", "Jing", "" ], [ "Bachman", "Phillip", "" ], [ "Suleman", "Kaheer", "" ] ]
TITLE: A Parallel-Hierarchical Model for Machine Comprehension on Sparse Data ABSTRACT: Understanding unstructured text is a major goal within natural language processing. Comprehension tests pose questions based on short text passages to evaluate such understanding. In this work, we investigate machine comprehension on the challenging {\it MCTest} benchmark. Partly because of its limited size, prior work on {\it MCTest} has focused mainly on engineering better features. We tackle the dataset with a neural approach, harnessing simple neural networks arranged in a parallel hierarchy. The parallel hierarchy enables our model to compare the passage, question, and answer from a variety of trainable perspectives, as opposed to using a manually designed, rigid feature set. Perspectives range from the word level to sentence fragments to sequences of sentences; the networks operate only on word-embedding representations of text. When trained with a methodology designed to help cope with limited training data, our Parallel-Hierarchical model sets a new state of the art for {\it MCTest}, outperforming previous feature-engineered approaches slightly and previous neural approaches by a significant margin (over 15\% absolute).
no_new_dataset
0.947721
1603.08907
Punarjay Chakravarty
Punarjay Chakravarty and Tinne Tuytelaars
Cross-modal Supervision for Learning Active Speaker Detection in Video
16 pages
null
null
null
cs.CV
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
In this paper, we show how to use audio to supervise the learning of active speaker detection in video. Voice Activity Detection (VAD) guides the learning of the vision-based classifier in a weakly supervised manner. The classifier uses spatio-temporal features to encode upper body motion - facial expressions and gesticulations associated with speaking. We further improve a generic model for active speaker detection by learning person specific models. Finally, we demonstrate the online adaptation of generic models learnt on one dataset, to previously unseen people in a new dataset, again using audio (VAD) for weak supervision. The use of temporal continuity overcomes the lack of clean training data. We are the first to present an active speaker detection system that learns on one audio-visual dataset and automatically adapts to speakers in a new dataset. This work can be seen as an example of how the availability of multi-modal data allows us to learn a model without the need for supervision, by transferring knowledge from one modality to another.
[ { "version": "v1", "created": "Tue, 29 Mar 2016 19:47:46 GMT" } ]
2016-03-30T00:00:00
[ [ "Chakravarty", "Punarjay", "" ], [ "Tuytelaars", "Tinne", "" ] ]
TITLE: Cross-modal Supervision for Learning Active Speaker Detection in Video ABSTRACT: In this paper, we show how to use audio to supervise the learning of active speaker detection in video. Voice Activity Detection (VAD) guides the learning of the vision-based classifier in a weakly supervised manner. The classifier uses spatio-temporal features to encode upper body motion - facial expressions and gesticulations associated with speaking. We further improve a generic model for active speaker detection by learning person specific models. Finally, we demonstrate the online adaptation of generic models learnt on one dataset, to previously unseen people in a new dataset, again using audio (VAD) for weak supervision. The use of temporal continuity overcomes the lack of clean training data. We are the first to present an active speaker detection system that learns on one audio-visual dataset and automatically adapts to speakers in a new dataset. This work can be seen as an example of how the availability of multi-modal data allows us to learn a model without the need for supervision, by transferring knowledge from one modality to another.
no_new_dataset
0.946051
1404.4078
Feng Lin
Xia Li, Feng Lin, Robert C. Qiu
Modeling Massive Amount of Experimental Data with Large Random Matrices in a Real-Time UWB-MIMO System
4 pages, 11 figures
null
null
null
cs.IT math.IT
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The aim of this paper is to study data modeling for massive datasets. Large random matrices are used to model the massive amount of data collected from our experimental testbed. This testbed was developed for a real-time ultra-wideband, multiple input multiple output (UWB-MIMO) system. Empirical spectral density is the relevant information we seek for. After we treat this UWB-MIMO system as a black box, we aim to model the output of the black box as a large statistical system, whose outputs can be described by (large) random matrices. This model is extremely general to allow for the study of non-linear and non-Gaussian phenomenon. The good agreements between the theoretical predictions and the empirical findings validate the correctness of the our suggested data model.
[ { "version": "v1", "created": "Tue, 15 Apr 2014 20:57:17 GMT" }, { "version": "v2", "created": "Sun, 27 Mar 2016 20:08:13 GMT" } ]
2016-03-29T00:00:00
[ [ "Li", "Xia", "" ], [ "Lin", "Feng", "" ], [ "Qiu", "Robert C.", "" ] ]
TITLE: Modeling Massive Amount of Experimental Data with Large Random Matrices in a Real-Time UWB-MIMO System ABSTRACT: The aim of this paper is to study data modeling for massive datasets. Large random matrices are used to model the massive amount of data collected from our experimental testbed. This testbed was developed for a real-time ultra-wideband, multiple input multiple output (UWB-MIMO) system. Empirical spectral density is the relevant information we seek for. After we treat this UWB-MIMO system as a black box, we aim to model the output of the black box as a large statistical system, whose outputs can be described by (large) random matrices. This model is extremely general to allow for the study of non-linear and non-Gaussian phenomenon. The good agreements between the theoretical predictions and the empirical findings validate the correctness of the our suggested data model.
no_new_dataset
0.946597
1511.04108
Ming Tan
Ming Tan, Cicero dos Santos, Bing Xiang, Bowen Zhou
LSTM-based Deep Learning Models for Non-factoid Answer Selection
added new experiments on TREC-QA
null
null
null
cs.CL cs.LG
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
In this paper, we apply a general deep learning (DL) framework for the answer selection task, which does not depend on manually defined features or linguistic tools. The basic framework is to build the embeddings of questions and answers based on bidirectional long short-term memory (biLSTM) models, and measure their closeness by cosine similarity. We further extend this basic model in two directions. One direction is to define a more composite representation for questions and answers by combining convolutional neural network with the basic framework. The other direction is to utilize a simple but efficient attention mechanism in order to generate the answer representation according to the question context. Several variations of models are provided. The models are examined by two datasets, including TREC-QA and InsuranceQA. Experimental results demonstrate that the proposed models substantially outperform several strong baselines.
[ { "version": "v1", "created": "Thu, 12 Nov 2015 22:01:54 GMT" }, { "version": "v2", "created": "Wed, 18 Nov 2015 15:00:46 GMT" }, { "version": "v3", "created": "Thu, 7 Jan 2016 17:56:29 GMT" }, { "version": "v4", "created": "Mon, 28 Mar 2016 04:12:45 GMT" } ]
2016-03-29T00:00:00
[ [ "Tan", "Ming", "" ], [ "Santos", "Cicero dos", "" ], [ "Xiang", "Bing", "" ], [ "Zhou", "Bowen", "" ] ]
TITLE: LSTM-based Deep Learning Models for Non-factoid Answer Selection ABSTRACT: In this paper, we apply a general deep learning (DL) framework for the answer selection task, which does not depend on manually defined features or linguistic tools. The basic framework is to build the embeddings of questions and answers based on bidirectional long short-term memory (biLSTM) models, and measure their closeness by cosine similarity. We further extend this basic model in two directions. One direction is to define a more composite representation for questions and answers by combining convolutional neural network with the basic framework. The other direction is to utilize a simple but efficient attention mechanism in order to generate the answer representation according to the question context. Several variations of models are provided. The models are examined by two datasets, including TREC-QA and InsuranceQA. Experimental results demonstrate that the proposed models substantially outperform several strong baselines.
no_new_dataset
0.947817
1601.00072
Mishal Almazrooie Mr
Mishal Almazrooie, Mogana Vadiveloo, and Rosni Abdullah
GPU-Based Fuzzy C-Means Clustering Algorithm for Image Segmentation
null
null
null
null
cs.DC cs.CV
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
In this paper, a fast and practical GPU-based implementation of Fuzzy C-Means(FCM) clustering algorithm for image segmentation is proposed. First, an extensive analysis is conducted to study the dependency among the image pixels in the algorithm for parallelization. The proposed GPU-based FCM has been tested on digital brain simulated dataset to segment white matter(WM), gray matter(GM) and cerebrospinal fluid (CSF) soft tissue regions. The execution time of the sequential FCM is 519 seconds for an image dataset with the size of 1MB. While the proposed GPU-based FCM requires only 2.33 seconds for the similar size of image dataset. An estimated 245-fold speedup is measured for the data size of 40 KB on a CUDA device that has 448 processors.
[ { "version": "v1", "created": "Fri, 1 Jan 2016 11:18:31 GMT" }, { "version": "v2", "created": "Wed, 6 Jan 2016 02:27:45 GMT" }, { "version": "v3", "created": "Mon, 28 Mar 2016 09:47:29 GMT" } ]
2016-03-29T00:00:00
[ [ "Almazrooie", "Mishal", "" ], [ "Vadiveloo", "Mogana", "" ], [ "Abdullah", "Rosni", "" ] ]
TITLE: GPU-Based Fuzzy C-Means Clustering Algorithm for Image Segmentation ABSTRACT: In this paper, a fast and practical GPU-based implementation of Fuzzy C-Means(FCM) clustering algorithm for image segmentation is proposed. First, an extensive analysis is conducted to study the dependency among the image pixels in the algorithm for parallelization. The proposed GPU-based FCM has been tested on digital brain simulated dataset to segment white matter(WM), gray matter(GM) and cerebrospinal fluid (CSF) soft tissue regions. The execution time of the sequential FCM is 519 seconds for an image dataset with the size of 1MB. While the proposed GPU-based FCM requires only 2.33 seconds for the similar size of image dataset. An estimated 245-fold speedup is measured for the data size of 40 KB on a CUDA device that has 448 processors.
no_new_dataset
0.953188
1601.05270
Sidra Faisal
Sidra Faisal, Kemele M. Endris, Saeedeh Shekarpour, S\"oren Auer
Co-evolution of RDF Datasets
18 pages, 4 figures, Accepted in ICWE, 2016
null
null
null
cs.DB
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Linking Data initiatives have fostered the publication of large number of RDF datasets in the Linked Open Data (LOD) cloud, as well as the development of query processing infrastructures to access these data in a federated fashion. However, different experimental studies have shown that availability of LOD datasets cannot be always ensured, being RDF data replication required for envisioning reliable federated query frameworks. Albeit enhancing data availability, RDF data replication requires synchronization and conflict resolution when replicas and source datasets are allowed to change data over time, i.e., co-evolution management needs to be provided to ensure consistency. In this paper, we tackle the problem of RDF data co-evolution and devise an approach for conflict resolution during co-evolution of RDF datasets. Our proposed approach is property-oriented and allows for exploiting semantics about RDF properties during co-evolution management. The quality of our approach is empirically evaluated in different scenarios on the DBpedia-live dataset. Experimental results suggest that proposed proposed techniques have a positive impact on the quality of data in source datasets and replicas.
[ { "version": "v1", "created": "Wed, 20 Jan 2016 13:46:24 GMT" }, { "version": "v2", "created": "Mon, 28 Mar 2016 18:21:40 GMT" } ]
2016-03-29T00:00:00
[ [ "Faisal", "Sidra", "" ], [ "Endris", "Kemele M.", "" ], [ "Shekarpour", "Saeedeh", "" ], [ "Auer", "Sören", "" ] ]
TITLE: Co-evolution of RDF Datasets ABSTRACT: Linking Data initiatives have fostered the publication of large number of RDF datasets in the Linked Open Data (LOD) cloud, as well as the development of query processing infrastructures to access these data in a federated fashion. However, different experimental studies have shown that availability of LOD datasets cannot be always ensured, being RDF data replication required for envisioning reliable federated query frameworks. Albeit enhancing data availability, RDF data replication requires synchronization and conflict resolution when replicas and source datasets are allowed to change data over time, i.e., co-evolution management needs to be provided to ensure consistency. In this paper, we tackle the problem of RDF data co-evolution and devise an approach for conflict resolution during co-evolution of RDF datasets. Our proposed approach is property-oriented and allows for exploiting semantics about RDF properties during co-evolution management. The quality of our approach is empirically evaluated in different scenarios on the DBpedia-live dataset. Experimental results suggest that proposed proposed techniques have a positive impact on the quality of data in source datasets and replicas.
no_new_dataset
0.94428
1603.08028
Daniel Cullina
Daniel Cullina, Kushagra Singhal, Negar Kiyavash, Prateek Mittal
On the Simultaneous Preservation of Privacy and Community Structure in Anonymized Networks
10 pages
null
null
null
cs.LG cs.CR cs.SI
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We consider the problem of performing community detection on a network, while maintaining privacy, assuming that the adversary has access to an auxiliary correlated network. We ask the question "Does there exist a regime where the network cannot be deanonymized perfectly, yet the community structure could be learned?." To answer this question, we derive information theoretic converses for the perfect deanonymization problem using the Stochastic Block Model and edge sub-sampling. We also provide an almost tight achievability result for perfect deanonymization. We also evaluate the performance of percolation based deanonymization algorithm on Stochastic Block Model data-sets that satisfy the conditions of our converse. Although our converse applies to exact deanonymization, the algorithm fails drastically when the conditions of the converse are met. Additionally, we study the effect of edge sub-sampling on the community structure of a real world dataset. Results show that the dataset falls under the purview of the idea of this paper. There results suggest that it may be possible to prove stronger partial deanonymizability converses, which would enable better privacy guarantees.
[ { "version": "v1", "created": "Fri, 25 Mar 2016 20:45:32 GMT" } ]
2016-03-29T00:00:00
[ [ "Cullina", "Daniel", "" ], [ "Singhal", "Kushagra", "" ], [ "Kiyavash", "Negar", "" ], [ "Mittal", "Prateek", "" ] ]
TITLE: On the Simultaneous Preservation of Privacy and Community Structure in Anonymized Networks ABSTRACT: We consider the problem of performing community detection on a network, while maintaining privacy, assuming that the adversary has access to an auxiliary correlated network. We ask the question "Does there exist a regime where the network cannot be deanonymized perfectly, yet the community structure could be learned?." To answer this question, we derive information theoretic converses for the perfect deanonymization problem using the Stochastic Block Model and edge sub-sampling. We also provide an almost tight achievability result for perfect deanonymization. We also evaluate the performance of percolation based deanonymization algorithm on Stochastic Block Model data-sets that satisfy the conditions of our converse. Although our converse applies to exact deanonymization, the algorithm fails drastically when the conditions of the converse are met. Additionally, we study the effect of edge sub-sampling on the community structure of a real world dataset. Results show that the dataset falls under the purview of the idea of this paper. There results suggest that it may be possible to prove stronger partial deanonymizability converses, which would enable better privacy guarantees.
no_new_dataset
0.940134
1603.08067
Bo Li
Bo Li and Tianfu Wu and Caiming Xiong and Song-Chun Zhu
Recognizing Car Fluents from Video
Accepted by CVPR 2016
null
null
null
cs.CV
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Physical fluents, a term originally used by Newton [40], refers to time-varying object states in dynamic scenes. In this paper, we are interested in inferring the fluents of vehicles from video. For example, a door (hood, trunk) is open or closed through various actions, light is blinking to turn. Recognizing these fluents has broad applications, yet have received scant attention in the computer vision literature. Car fluent recognition entails a unified framework for car detection, car part localization and part status recognition, which is made difficult by large structural and appearance variations, low resolutions and occlusions. This paper learns a spatial-temporal And-Or hierarchical model to represent car fluents. The learning of this model is formulated under the latent structural SVM framework. Since there are no publicly related dataset, we collect and annotate a car fluent dataset consisting of car videos with diverse fluents. In experiments, the proposed method outperforms several highly related baseline methods in terms of car fluent recognition and car part localization.
[ { "version": "v1", "created": "Sat, 26 Mar 2016 03:45:00 GMT" } ]
2016-03-29T00:00:00
[ [ "Li", "Bo", "" ], [ "Wu", "Tianfu", "" ], [ "Xiong", "Caiming", "" ], [ "Zhu", "Song-Chun", "" ] ]
TITLE: Recognizing Car Fluents from Video ABSTRACT: Physical fluents, a term originally used by Newton [40], refers to time-varying object states in dynamic scenes. In this paper, we are interested in inferring the fluents of vehicles from video. For example, a door (hood, trunk) is open or closed through various actions, light is blinking to turn. Recognizing these fluents has broad applications, yet have received scant attention in the computer vision literature. Car fluent recognition entails a unified framework for car detection, car part localization and part status recognition, which is made difficult by large structural and appearance variations, low resolutions and occlusions. This paper learns a spatial-temporal And-Or hierarchical model to represent car fluents. The learning of this model is formulated under the latent structural SVM framework. Since there are no publicly related dataset, we collect and annotate a car fluent dataset consisting of car videos with diverse fluents. In experiments, the proposed method outperforms several highly related baseline methods in terms of car fluent recognition and car part localization.
new_dataset
0.960287
1603.08092
Jianyu Tang
Jianyu Tang, Hanzi Wang and Yan Yan
Learning Hough Regression Models via Bridge Partial Least Squares for Object Detection
null
Neurocomputing, 2015,152(3):236-249
10.1016/j.neucom.2014.10.071
null
cs.CV
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Popular Hough Transform-based object detection approaches usually construct an appearance codebook by clustering local image features. However, how to choose appropriate values for the parameters used in the clustering step remains an open problem. Moreover, some popular histogram features extracted from overlapping image blocks may cause a high degree of redundancy and multicollinearity. In this paper, we propose a novel Hough Transform-based object detection approach. First, to address the above issues, we exploit a Bridge Partial Least Squares (BPLS) technique to establish context-encoded Hough Regression Models (HRMs), which are linear regression models that cast probabilistic Hough votes to predict object locations. BPLS is an efficient variant of Partial Least Squares (PLS). PLS-based regression techniques (including BPLS) can reduce the redundancy and eliminate the multicollinearity of a feature set. And the appropriate value of the only parameter used in PLS (i.e., the number of latent components) can be determined by using a cross-validation procedure. Second, to efficiently handle object scale changes, we propose a novel multi-scale voting scheme. In this scheme, multiple Hough images corresponding to multiple object scales can be obtained simultaneously. Third, an object in a test image may correspond to multiple true and false positive hypotheses at different scales. Based on the proposed multi-scale voting scheme, a principled strategy is proposed to fuse hypotheses to reduce false positives by evaluating normalized pointwise mutual information between hypotheses. In the experiments, we also compare the proposed HRM approach with its several variants to evaluate the influences of its components on its performance. Experimental results show that the proposed HRM approach has achieved desirable performances on popular benchmark datasets.
[ { "version": "v1", "created": "Sat, 26 Mar 2016 09:33:30 GMT" } ]
2016-03-29T00:00:00
[ [ "Tang", "Jianyu", "" ], [ "Wang", "Hanzi", "" ], [ "Yan", "Yan", "" ] ]
TITLE: Learning Hough Regression Models via Bridge Partial Least Squares for Object Detection ABSTRACT: Popular Hough Transform-based object detection approaches usually construct an appearance codebook by clustering local image features. However, how to choose appropriate values for the parameters used in the clustering step remains an open problem. Moreover, some popular histogram features extracted from overlapping image blocks may cause a high degree of redundancy and multicollinearity. In this paper, we propose a novel Hough Transform-based object detection approach. First, to address the above issues, we exploit a Bridge Partial Least Squares (BPLS) technique to establish context-encoded Hough Regression Models (HRMs), which are linear regression models that cast probabilistic Hough votes to predict object locations. BPLS is an efficient variant of Partial Least Squares (PLS). PLS-based regression techniques (including BPLS) can reduce the redundancy and eliminate the multicollinearity of a feature set. And the appropriate value of the only parameter used in PLS (i.e., the number of latent components) can be determined by using a cross-validation procedure. Second, to efficiently handle object scale changes, we propose a novel multi-scale voting scheme. In this scheme, multiple Hough images corresponding to multiple object scales can be obtained simultaneously. Third, an object in a test image may correspond to multiple true and false positive hypotheses at different scales. Based on the proposed multi-scale voting scheme, a principled strategy is proposed to fuse hypotheses to reduce false positives by evaluating normalized pointwise mutual information between hypotheses. In the experiments, we also compare the proposed HRM approach with its several variants to evaluate the influences of its components on its performance. Experimental results show that the proposed HRM approach has achieved desirable performances on popular benchmark datasets.
no_new_dataset
0.94801
1603.08105
Ayush Mittal
Ayush Mittal, Anant Raj, Vinay P. Namboodiri and Tinne Tuytelaars
Unsupervised Domain Adaptation in the Wild: Dealing with Asymmetric Label Sets
supplementary material: http://home.iitk.ac.in/~ayushmi/supplementary-material-unsupervised.pdf
null
null
null
cs.CV
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The goal of domain adaptation is to adapt models learned on a source domain to a particular target domain. Most methods for unsupervised domain adaptation proposed in the literature to date, assume that the set of classes present in the target domain is identical to the set of classes present in the source domain. This is a restrictive assumption that limits the practical applicability of unsupervised domain adaptation techniques in real world settings ("in the wild"). Therefore, we relax this constraint and propose a technique that allows the set of target classes to be a subset of the source classes. This way, large publicly available annotated datasets with a wide variety of classes can be used as source, even if the actual set of classes in target can be more limited and, maybe most importantly, unknown beforehand. To this end, we propose an algorithm that orders a set of source subspaces that are relevant to the target classification problem. Our method then chooses a restricted set from this ordered set of source subspaces. As an extension, even starting from multiple source datasets with varied sets of categories, this method automatically selects an appropriate subset of source categories relevant to a target dataset. Empirical analysis on a number of source and target domain datasets shows that restricting the source subspace to only a subset of categories does indeed substantially improve the eventual target classification accuracy over the baseline that considers all source classes.
[ { "version": "v1", "created": "Sat, 26 Mar 2016 13:22:55 GMT" } ]
2016-03-29T00:00:00
[ [ "Mittal", "Ayush", "" ], [ "Raj", "Anant", "" ], [ "Namboodiri", "Vinay P.", "" ], [ "Tuytelaars", "Tinne", "" ] ]
TITLE: Unsupervised Domain Adaptation in the Wild: Dealing with Asymmetric Label Sets ABSTRACT: The goal of domain adaptation is to adapt models learned on a source domain to a particular target domain. Most methods for unsupervised domain adaptation proposed in the literature to date, assume that the set of classes present in the target domain is identical to the set of classes present in the source domain. This is a restrictive assumption that limits the practical applicability of unsupervised domain adaptation techniques in real world settings ("in the wild"). Therefore, we relax this constraint and propose a technique that allows the set of target classes to be a subset of the source classes. This way, large publicly available annotated datasets with a wide variety of classes can be used as source, even if the actual set of classes in target can be more limited and, maybe most importantly, unknown beforehand. To this end, we propose an algorithm that orders a set of source subspaces that are relevant to the target classification problem. Our method then chooses a restricted set from this ordered set of source subspaces. As an extension, even starting from multiple source datasets with varied sets of categories, this method automatically selects an appropriate subset of source categories relevant to a target dataset. Empirical analysis on a number of source and target domain datasets shows that restricting the source subspace to only a subset of categories does indeed substantially improve the eventual target classification accuracy over the baseline that considers all source classes.
no_new_dataset
0.946448
1603.08124
Wenbin Li
Wenbin Li, Darren Cosker
Video Interpolation using Optical Flow and Laplacian Smoothness
null
null
null
null
cs.CV
http://creativecommons.org/licenses/by-nc-sa/4.0/
Non-rigid video interpolation is a common computer vision task. In this paper we present an optical flow approach which adopts a Laplacian Cotangent Mesh constraint to enhance the local smoothness. Similar to Li et al., our approach adopts a mesh to the image with a resolution up to one vertex per pixel and uses angle constraints to ensure sensible local deformations between image pairs. The Laplacian Mesh constraints are expressed wholly inside the optical flow optimization, and can be applied in a straightforward manner to a wide range of image tracking and registration problems. We evaluate our approach by testing on several benchmark datasets, including the Middlebury and Garg et al. datasets. In addition, we show application of our method for constructing 3D Morphable Facial Models from dynamic 3D data.
[ { "version": "v1", "created": "Sat, 26 Mar 2016 17:13:25 GMT" } ]
2016-03-29T00:00:00
[ [ "Li", "Wenbin", "" ], [ "Cosker", "Darren", "" ] ]
TITLE: Video Interpolation using Optical Flow and Laplacian Smoothness ABSTRACT: Non-rigid video interpolation is a common computer vision task. In this paper we present an optical flow approach which adopts a Laplacian Cotangent Mesh constraint to enhance the local smoothness. Similar to Li et al., our approach adopts a mesh to the image with a resolution up to one vertex per pixel and uses angle constraints to ensure sensible local deformations between image pairs. The Laplacian Mesh constraints are expressed wholly inside the optical flow optimization, and can be applied in a straightforward manner to a wide range of image tracking and registration problems. We evaluate our approach by testing on several benchmark datasets, including the Middlebury and Garg et al. datasets. In addition, we show application of our method for constructing 3D Morphable Facial Models from dynamic 3D data.
no_new_dataset
0.957636
1603.08212
Ethan Fetaya
Ita Lifshitz, Ethan Fetaya and Shimon Ullman
Human Pose Estimation using Deep Consensus Voting
null
null
null
null
cs.CV cs.LG
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
In this paper we consider the problem of human pose estimation from a single still image. We propose a novel approach where each location in the image votes for the position of each keypoint using a convolutional neural net. The voting scheme allows us to utilize information from the whole image, rather than rely on a sparse set of keypoint locations. Using dense, multi-target votes, not only produces good keypoint predictions, but also enables us to compute image-dependent joint keypoint probabilities by looking at consensus voting. This differs from most previous methods where joint probabilities are learned from relative keypoint locations and are independent of the image. We finally combine the keypoints votes and joint probabilities in order to identify the optimal pose configuration. We show our competitive performance on the MPII Human Pose and Leeds Sports Pose datasets.
[ { "version": "v1", "created": "Sun, 27 Mar 2016 12:45:33 GMT" } ]
2016-03-29T00:00:00
[ [ "Lifshitz", "Ita", "" ], [ "Fetaya", "Ethan", "" ], [ "Ullman", "Shimon", "" ] ]
TITLE: Human Pose Estimation using Deep Consensus Voting ABSTRACT: In this paper we consider the problem of human pose estimation from a single still image. We propose a novel approach where each location in the image votes for the position of each keypoint using a convolutional neural net. The voting scheme allows us to utilize information from the whole image, rather than rely on a sparse set of keypoint locations. Using dense, multi-target votes, not only produces good keypoint predictions, but also enables us to compute image-dependent joint keypoint probabilities by looking at consensus voting. This differs from most previous methods where joint probabilities are learned from relative keypoint locations and are independent of the image. We finally combine the keypoints votes and joint probabilities in order to identify the optimal pose configuration. We show our competitive performance on the MPII Human Pose and Leeds Sports Pose datasets.
no_new_dataset
0.951278
1603.08252
Ajay Saini
Ajay Saini, Natasha Markuzon
Predictive Modeling of Opinion and Connectivity Dynamics in Social Networks
19 pages
null
null
null
cs.SI physics.soc-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Recent years saw an increased interest in modeling and understanding the mechanisms of opinion and innovation spread through human networks. Using analysis of real-world social data, researchers are able to gain a better understanding of the dynamics of social networks and subsequently model the changes in such networks over time. We developed a social network model that both utilizes an agent-based approach with a dynamic update of opinions and connections between agents and reflects opinion propagation and structural changes over time as observed in real-world data. We validate the model using data from the Social Evolution dataset of the MIT Human Dynamics Lab describing changes in friendships and health self-perception in a targeted student population over a nine-month period. We demonstrate the effectiveness of the approach by predicting changes in both opinion spread and connectivity of the network. We also use the model to evaluate how the network parameters, such as the level of `openness' and willingness to incorporate opinions of neighboring agents, affect the outcome. The model not only provides insight into the dynamics of ever changing social networks, but also presents a tool with which one can investigate opinion propagation strategies for networks of various structures and opinion distributions.
[ { "version": "v1", "created": "Sun, 27 Mar 2016 19:53:21 GMT" } ]
2016-03-29T00:00:00
[ [ "Saini", "Ajay", "" ], [ "Markuzon", "Natasha", "" ] ]
TITLE: Predictive Modeling of Opinion and Connectivity Dynamics in Social Networks ABSTRACT: Recent years saw an increased interest in modeling and understanding the mechanisms of opinion and innovation spread through human networks. Using analysis of real-world social data, researchers are able to gain a better understanding of the dynamics of social networks and subsequently model the changes in such networks over time. We developed a social network model that both utilizes an agent-based approach with a dynamic update of opinions and connections between agents and reflects opinion propagation and structural changes over time as observed in real-world data. We validate the model using data from the Social Evolution dataset of the MIT Human Dynamics Lab describing changes in friendships and health self-perception in a targeted student population over a nine-month period. We demonstrate the effectiveness of the approach by predicting changes in both opinion spread and connectivity of the network. We also use the model to evaluate how the network parameters, such as the level of `openness' and willingness to incorporate opinions of neighboring agents, affect the outcome. The model not only provides insight into the dynamics of ever changing social networks, but also presents a tool with which one can investigate opinion propagation strategies for networks of various structures and opinion distributions.
no_new_dataset
0.95096
1603.08321
Linlin Chao
Linlin Chao, Jianhua Tao, Minghao Yang, Ya Li and Zhengqi Wen
Audio Visual Emotion Recognition with Temporal Alignment and Perception Attention
null
null
null
null
cs.CV cs.CL cs.LG
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
This paper focuses on two key problems for audio-visual emotion recognition in the video. One is the audio and visual streams temporal alignment for feature level fusion. The other one is locating and re-weighting the perception attentions in the whole audio-visual stream for better recognition. The Long Short Term Memory Recurrent Neural Network (LSTM-RNN) is employed as the main classification architecture. Firstly, soft attention mechanism aligns the audio and visual streams. Secondly, seven emotion embedding vectors, which are corresponding to each classification emotion type, are added to locate the perception attentions. The locating and re-weighting process is also based on the soft attention mechanism. The experiment results on EmotiW2015 dataset and the qualitative analysis show the efficiency of the proposed two techniques.
[ { "version": "v1", "created": "Mon, 28 Mar 2016 06:06:10 GMT" } ]
2016-03-29T00:00:00
[ [ "Chao", "Linlin", "" ], [ "Tao", "Jianhua", "" ], [ "Yang", "Minghao", "" ], [ "Li", "Ya", "" ], [ "Wen", "Zhengqi", "" ] ]
TITLE: Audio Visual Emotion Recognition with Temporal Alignment and Perception Attention ABSTRACT: This paper focuses on two key problems for audio-visual emotion recognition in the video. One is the audio and visual streams temporal alignment for feature level fusion. The other one is locating and re-weighting the perception attentions in the whole audio-visual stream for better recognition. The Long Short Term Memory Recurrent Neural Network (LSTM-RNN) is employed as the main classification architecture. Firstly, soft attention mechanism aligns the audio and visual streams. Secondly, seven emotion embedding vectors, which are corresponding to each classification emotion type, are added to locate the perception attentions. The locating and re-weighting process is also based on the soft attention mechanism. The experiment results on EmotiW2015 dataset and the qualitative analysis show the efficiency of the proposed two techniques.
no_new_dataset
0.952574
1603.08486
Hoo Chang Shin
Hoo-Chang Shin, Kirk Roberts, Le Lu, Dina Demner-Fushman, Jianhua Yao, Ronald M Summers
Learning to Read Chest X-Rays: Recurrent Neural Cascade Model for Automated Image Annotation
null
null
null
null
cs.CV
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Despite the recent advances in automatically describing image contents, their applications have been mostly limited to image caption datasets containing natural images (e.g., Flickr 30k, MSCOCO). In this paper, we present a deep learning model to efficiently detect a disease from an image and annotate its contexts (e.g., location, severity and the affected organs). We employ a publicly available radiology dataset of chest x-rays and their reports, and use its image annotations to mine disease names to train convolutional neural networks (CNNs). In doing so, we adopt various regularization techniques to circumvent the large normal-vs-diseased cases bias. Recurrent neural networks (RNNs) are then trained to describe the contexts of a detected disease, based on the deep CNN features. Moreover, we introduce a novel approach to use the weights of the already trained pair of CNN/RNN on the domain-specific image/text dataset, to infer the joint image/text contexts for composite image labeling. Significantly improved image annotation results are demonstrated using the recurrent neural cascade model by taking the joint image/text contexts into account.
[ { "version": "v1", "created": "Mon, 28 Mar 2016 19:02:07 GMT" } ]
2016-03-29T00:00:00
[ [ "Shin", "Hoo-Chang", "" ], [ "Roberts", "Kirk", "" ], [ "Lu", "Le", "" ], [ "Demner-Fushman", "Dina", "" ], [ "Yao", "Jianhua", "" ], [ "Summers", "Ronald M", "" ] ]
TITLE: Learning to Read Chest X-Rays: Recurrent Neural Cascade Model for Automated Image Annotation ABSTRACT: Despite the recent advances in automatically describing image contents, their applications have been mostly limited to image caption datasets containing natural images (e.g., Flickr 30k, MSCOCO). In this paper, we present a deep learning model to efficiently detect a disease from an image and annotate its contexts (e.g., location, severity and the affected organs). We employ a publicly available radiology dataset of chest x-rays and their reports, and use its image annotations to mine disease names to train convolutional neural networks (CNNs). In doing so, we adopt various regularization techniques to circumvent the large normal-vs-diseased cases bias. Recurrent neural networks (RNNs) are then trained to describe the contexts of a detected disease, based on the deep CNN features. Moreover, we introduce a novel approach to use the weights of the already trained pair of CNN/RNN on the domain-specific image/text dataset, to infer the joint image/text contexts for composite image labeling. Significantly improved image annotation results are demonstrated using the recurrent neural cascade model by taking the joint image/text contexts into account.
no_new_dataset
0.945147
1603.08507
Lisa Anne Hendricks
Lisa Anne Hendricks, Zeynep Akata, Marcus Rohrbach, Jeff Donahue, Bernt Schiele, Trevor Darrell
Generating Visual Explanations
null
null
null
null
cs.CV cs.AI cs.CL
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Clearly explaining a rationale for a classification decision to an end-user can be as important as the decision itself. Existing approaches for deep visual recognition are generally opaque and do not output any justification text; contemporary vision-language models can describe image content but fail to take into account class-discriminative image aspects which justify visual predictions. We propose a new model that focuses on the discriminating properties of the visible object, jointly predicts a class label, and explains why the predicted label is appropriate for the image. We propose a novel loss function based on sampling and reinforcement learning that learns to generate sentences that realize a global sentence property, such as class specificity. Our results on a fine-grained bird species classification dataset show that our model is able to generate explanations which are not only consistent with an image but also more discriminative than descriptions produced by existing captioning methods.
[ { "version": "v1", "created": "Mon, 28 Mar 2016 19:54:12 GMT" } ]
2016-03-29T00:00:00
[ [ "Hendricks", "Lisa Anne", "" ], [ "Akata", "Zeynep", "" ], [ "Rohrbach", "Marcus", "" ], [ "Donahue", "Jeff", "" ], [ "Schiele", "Bernt", "" ], [ "Darrell", "Trevor", "" ] ]
TITLE: Generating Visual Explanations ABSTRACT: Clearly explaining a rationale for a classification decision to an end-user can be as important as the decision itself. Existing approaches for deep visual recognition are generally opaque and do not output any justification text; contemporary vision-language models can describe image content but fail to take into account class-discriminative image aspects which justify visual predictions. We propose a new model that focuses on the discriminating properties of the visible object, jointly predicts a class label, and explains why the predicted label is appropriate for the image. We propose a novel loss function based on sampling and reinforcement learning that learns to generate sentences that realize a global sentence property, such as class specificity. Our results on a fine-grained bird species classification dataset show that our model is able to generate explanations which are not only consistent with an image but also more discriminative than descriptions produced by existing captioning methods.
no_new_dataset
0.951414
1505.01197
Georgia Gkioxari
Georgia Gkioxari, Ross Girshick, Jitendra Malik
Contextual Action Recognition with R*CNN
null
null
null
null
cs.CV
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
There are multiple cues in an image which reveal what action a person is performing. For example, a jogger has a pose that is characteristic for jogging, but the scene (e.g. road, trail) and the presence of other joggers can be an additional source of information. In this work, we exploit the simple observation that actions are accompanied by contextual cues to build a strong action recognition system. We adapt RCNN to use more than one region for classification while still maintaining the ability to localize the action. We call our system R*CNN. The action-specific models and the feature maps are trained jointly, allowing for action specific representations to emerge. R*CNN achieves 90.2% mean AP on the PASAL VOC Action dataset, outperforming all other approaches in the field by a significant margin. Last, we show that R*CNN is not limited to action recognition. In particular, R*CNN can also be used to tackle fine-grained tasks such as attribute classification. We validate this claim by reporting state-of-the-art performance on the Berkeley Attributes of People dataset.
[ { "version": "v1", "created": "Tue, 5 May 2015 21:56:10 GMT" }, { "version": "v2", "created": "Sat, 26 Sep 2015 20:29:26 GMT" }, { "version": "v3", "created": "Fri, 25 Mar 2016 01:06:01 GMT" } ]
2016-03-28T00:00:00
[ [ "Gkioxari", "Georgia", "" ], [ "Girshick", "Ross", "" ], [ "Malik", "Jitendra", "" ] ]
TITLE: Contextual Action Recognition with R*CNN ABSTRACT: There are multiple cues in an image which reveal what action a person is performing. For example, a jogger has a pose that is characteristic for jogging, but the scene (e.g. road, trail) and the presence of other joggers can be an additional source of information. In this work, we exploit the simple observation that actions are accompanied by contextual cues to build a strong action recognition system. We adapt RCNN to use more than one region for classification while still maintaining the ability to localize the action. We call our system R*CNN. The action-specific models and the feature maps are trained jointly, allowing for action specific representations to emerge. R*CNN achieves 90.2% mean AP on the PASAL VOC Action dataset, outperforming all other approaches in the field by a significant margin. Last, we show that R*CNN is not limited to action recognition. In particular, R*CNN can also be used to tackle fine-grained tasks such as attribute classification. We validate this claim by reporting state-of-the-art performance on the Berkeley Attributes of People dataset.
no_new_dataset
0.945349
1602.00417
Jumabek Alikhanov
Jumabek Alikhanov, Myeong Hyeon Ga, Seunghyun Ko and Geun-Sik Jo
Transfer Learning Based on AdaBoost for Feature Selection from Multiple ConvNet Layer Features
null
null
null
null
cs.CV
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Convolutional Networks (ConvNets) are powerful models that learn hierarchies of visual features, which could also be used to obtain image representations for transfer learning. The basic pipeline for transfer learning is to first train a ConvNet on a large dataset (source task) and then use feed-forward units activation of the trained ConvNet as image representation for smaller datasets (target task). Our key contribution is to demonstrate superior performance of multiple ConvNet layer features over single ConvNet layer features. Combining multiple ConvNet layer features will result in more complex feature space with some features being repetitive. This requires some form of feature selection. We use AdaBoost with single stumps to implicitly select only distinct features that are useful towards classification from concatenated ConvNet features. Experimental results show that using multiple ConvNet layer activation features instead of single ConvNet layer features consistently will produce superior performance. Improvements becomes significant as we increase the distance between source task and the target task.
[ { "version": "v1", "created": "Mon, 1 Feb 2016 08:02:06 GMT" }, { "version": "v2", "created": "Fri, 25 Mar 2016 12:03:49 GMT" } ]
2016-03-28T00:00:00
[ [ "Alikhanov", "Jumabek", "" ], [ "Ga", "Myeong Hyeon", "" ], [ "Ko", "Seunghyun", "" ], [ "Jo", "Geun-Sik", "" ] ]
TITLE: Transfer Learning Based on AdaBoost for Feature Selection from Multiple ConvNet Layer Features ABSTRACT: Convolutional Networks (ConvNets) are powerful models that learn hierarchies of visual features, which could also be used to obtain image representations for transfer learning. The basic pipeline for transfer learning is to first train a ConvNet on a large dataset (source task) and then use feed-forward units activation of the trained ConvNet as image representation for smaller datasets (target task). Our key contribution is to demonstrate superior performance of multiple ConvNet layer features over single ConvNet layer features. Combining multiple ConvNet layer features will result in more complex feature space with some features being repetitive. This requires some form of feature selection. We use AdaBoost with single stumps to implicitly select only distinct features that are useful towards classification from concatenated ConvNet features. Experimental results show that using multiple ConvNet layer activation features instead of single ConvNet layer features consistently will produce superior performance. Improvements becomes significant as we increase the distance between source task and the target task.
no_new_dataset
0.944177
1602.03534
Ozan Sener
Ozan Sener, Hyun Oh Song, Ashutosh Saxena, Silvio Savarese
Unsupervised Transductive Domain Adaptation
null
null
null
null
stat.ML cs.LG
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Supervised learning with large scale labeled datasets and deep layered models has made a paradigm shift in diverse areas in learning and recognition. However, this approach still suffers generalization issues under the presence of a domain shift between the training and the test data distribution. In this regard, unsupervised domain adaptation algorithms have been proposed to directly address the domain shift problem. In this paper, we approach the problem from a transductive perspective. We incorporate the domain shift and the transductive target inference into our framework by jointly solving for an asymmetric similarity metric and the optimal transductive target label assignment. We also show that our model can easily be extended for deep feature learning in order to learn features which are discriminative in the target domain. Our experiments show that the proposed method significantly outperforms state-of-the-art algorithms in both object recognition and digit classification experiments by a large margin.
[ { "version": "v1", "created": "Wed, 10 Feb 2016 21:07:23 GMT" }, { "version": "v2", "created": "Fri, 12 Feb 2016 22:37:36 GMT" }, { "version": "v3", "created": "Fri, 25 Mar 2016 16:47:54 GMT" } ]
2016-03-28T00:00:00
[ [ "Sener", "Ozan", "" ], [ "Song", "Hyun Oh", "" ], [ "Saxena", "Ashutosh", "" ], [ "Savarese", "Silvio", "" ] ]
TITLE: Unsupervised Transductive Domain Adaptation ABSTRACT: Supervised learning with large scale labeled datasets and deep layered models has made a paradigm shift in diverse areas in learning and recognition. However, this approach still suffers generalization issues under the presence of a domain shift between the training and the test data distribution. In this regard, unsupervised domain adaptation algorithms have been proposed to directly address the domain shift problem. In this paper, we approach the problem from a transductive perspective. We incorporate the domain shift and the transductive target inference into our framework by jointly solving for an asymmetric similarity metric and the optimal transductive target label assignment. We also show that our model can easily be extended for deep feature learning in order to learn features which are discriminative in the target domain. Our experiments show that the proposed method significantly outperforms state-of-the-art algorithms in both object recognition and digit classification experiments by a large margin.
no_new_dataset
0.944434
1603.07745
Ganesh Sundaramoorthi
Ganesh Sundaramoorthi, Naeemullah Khan, Byung-Woo Hong
Coarse-to-Fine Segmentation With Shape-Tailored Scale Spaces
null
null
null
null
cs.CV
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We formulate a general energy and method for segmentation that is designed to have preference for segmenting the coarse structure over the fine structure of the data, without smoothing across boundaries of regions. The energy is formulated by considering data terms at a continuum of scales from the scale space computed from the Heat Equation within regions, and integrating these terms over all time. We show that the energy may be approximately optimized without solving for the entire scale space, but rather solving time-independent linear equations at the native scale of the image, making the method computationally feasible. We provide a multi-region scheme, and apply our method to motion segmentation. Experiments on a benchmark dataset shows that our method is less sensitive to clutter or other undesirable fine-scale structure, and leads to better performance in motion segmentation.
[ { "version": "v1", "created": "Thu, 24 Mar 2016 20:39:24 GMT" } ]
2016-03-28T00:00:00
[ [ "Sundaramoorthi", "Ganesh", "" ], [ "Khan", "Naeemullah", "" ], [ "Hong", "Byung-Woo", "" ] ]
TITLE: Coarse-to-Fine Segmentation With Shape-Tailored Scale Spaces ABSTRACT: We formulate a general energy and method for segmentation that is designed to have preference for segmenting the coarse structure over the fine structure of the data, without smoothing across boundaries of regions. The energy is formulated by considering data terms at a continuum of scales from the scale space computed from the Heat Equation within regions, and integrating these terms over all time. We show that the energy may be approximately optimized without solving for the entire scale space, but rather solving time-independent linear equations at the native scale of the image, making the method computationally feasible. We provide a multi-region scheme, and apply our method to motion segmentation. Experiments on a benchmark dataset shows that our method is less sensitive to clutter or other undesirable fine-scale structure, and leads to better performance in motion segmentation.
no_new_dataset
0.952838
1603.07772
Wentao Zhu
Wentao Zhu, Cuiling Lan, Junliang Xing, Wenjun Zeng, Yanghao Li, Li Shen, Xiaohui Xie
Co-occurrence Feature Learning for Skeleton based Action Recognition using Regularized Deep LSTM Networks
AAAI 2016 conference
null
null
null
cs.CV cs.LG
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Skeleton based action recognition distinguishes human actions using the trajectories of skeleton joints, which provide a very good representation for describing actions. Considering that recurrent neural networks (RNNs) with Long Short-Term Memory (LSTM) can learn feature representations and model long-term temporal dependencies automatically, we propose an end-to-end fully connected deep LSTM network for skeleton based action recognition. Inspired by the observation that the co-occurrences of the joints intrinsically characterize human actions, we take the skeleton as the input at each time slot and introduce a novel regularization scheme to learn the co-occurrence features of skeleton joints. To train the deep LSTM network effectively, we propose a new dropout algorithm which simultaneously operates on the gates, cells, and output responses of the LSTM neurons. Experimental results on three human action recognition datasets consistently demonstrate the effectiveness of the proposed model.
[ { "version": "v1", "created": "Thu, 24 Mar 2016 22:43:55 GMT" } ]
2016-03-28T00:00:00
[ [ "Zhu", "Wentao", "" ], [ "Lan", "Cuiling", "" ], [ "Xing", "Junliang", "" ], [ "Zeng", "Wenjun", "" ], [ "Li", "Yanghao", "" ], [ "Shen", "Li", "" ], [ "Xie", "Xiaohui", "" ] ]
TITLE: Co-occurrence Feature Learning for Skeleton based Action Recognition using Regularized Deep LSTM Networks ABSTRACT: Skeleton based action recognition distinguishes human actions using the trajectories of skeleton joints, which provide a very good representation for describing actions. Considering that recurrent neural networks (RNNs) with Long Short-Term Memory (LSTM) can learn feature representations and model long-term temporal dependencies automatically, we propose an end-to-end fully connected deep LSTM network for skeleton based action recognition. Inspired by the observation that the co-occurrences of the joints intrinsically characterize human actions, we take the skeleton as the input at each time slot and introduce a novel regularization scheme to learn the co-occurrence features of skeleton joints. To train the deep LSTM network effectively, we propose a new dropout algorithm which simultaneously operates on the gates, cells, and output responses of the LSTM neurons. Experimental results on three human action recognition datasets consistently demonstrate the effectiveness of the proposed model.
no_new_dataset
0.946794
1603.07846
Wei Wang
Wei Wang, Gang Chen, Haibo Chen, Tien Tuan Anh Dinh, Jinyang Gao, Beng Chin Ooi, Kian-Lee Tan and Sheng Wang
Deep Learning At Scale and At Ease
submitted to TOMM (under review)
null
null
null
cs.LG cs.DC
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Recently, deep learning techniques have enjoyed success in various multimedia applications, such as image classification and multi-modal data analysis. Large deep learning models are developed for learning rich representations of complex data. There are two challenges to overcome before deep learning can be widely adopted in multimedia and other applications. One is usability, namely the implementation of different models and training algorithms must be done by non-experts without much effort especially when the model is large and complex. The other is scalability, that is the deep learning system must be able to provision for a huge demand of computing resources for training large models with massive datasets. To address these two challenges, in this paper, we design a distributed deep learning platform called SINGA which has an intuitive programming model based on the common layer abstraction of deep learning models. Good scalability is achieved through flexible distributed training architecture and specific optimization techniques. SINGA runs on GPUs as well as on CPUs, and we show that it outperforms many other state-of-the-art deep learning systems. Our experience with developing and training deep learning models for real-life multimedia applications in SINGA shows that the platform is both usable and scalable.
[ { "version": "v1", "created": "Fri, 25 Mar 2016 08:46:02 GMT" } ]
2016-03-28T00:00:00
[ [ "Wang", "Wei", "" ], [ "Chen", "Gang", "" ], [ "Chen", "Haibo", "" ], [ "Dinh", "Tien Tuan Anh", "" ], [ "Gao", "Jinyang", "" ], [ "Ooi", "Beng Chin", "" ], [ "Tan", "Kian-Lee", "" ], [ "Wang", "Sheng", "" ] ]
TITLE: Deep Learning At Scale and At Ease ABSTRACT: Recently, deep learning techniques have enjoyed success in various multimedia applications, such as image classification and multi-modal data analysis. Large deep learning models are developed for learning rich representations of complex data. There are two challenges to overcome before deep learning can be widely adopted in multimedia and other applications. One is usability, namely the implementation of different models and training algorithms must be done by non-experts without much effort especially when the model is large and complex. The other is scalability, that is the deep learning system must be able to provision for a huge demand of computing resources for training large models with massive datasets. To address these two challenges, in this paper, we design a distributed deep learning platform called SINGA which has an intuitive programming model based on the common layer abstraction of deep learning models. Good scalability is achieved through flexible distributed training architecture and specific optimization techniques. SINGA runs on GPUs as well as on CPUs, and we show that it outperforms many other state-of-the-art deep learning systems. Our experience with developing and training deep learning models for real-life multimedia applications in SINGA shows that the platform is both usable and scalable.
no_new_dataset
0.940353
1603.07849
Eric Makita
Eric Makita, Artem Lenskiy
A multinomial probabilistic model for movie genre predictions
5 pages, 4 figures, 8th International Conference on Machine Learning and Computing, Hong Kong
null
null
null
cs.IR cs.LG
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
This paper proposes a movie genre-prediction based on multinomial probability model. To the best of our knowledge, this problem has not been addressed yet in the field of recommender system. The prediction of a movie genre has many practical applications including complementing the items categories given by experts and providing a surprise effect in the recommendations given to a user. We employ mulitnomial event model to estimate a likelihood of a movie given genre and the Bayes rule to evaluate the posterior probability of a genre given a movie. Experiments with the MovieLens dataset validate our approach. We achieved 70% prediction rate using only 15% of the whole set for training.
[ { "version": "v1", "created": "Fri, 25 Mar 2016 08:49:39 GMT" } ]
2016-03-28T00:00:00
[ [ "Makita", "Eric", "" ], [ "Lenskiy", "Artem", "" ] ]
TITLE: A multinomial probabilistic model for movie genre predictions ABSTRACT: This paper proposes a movie genre-prediction based on multinomial probability model. To the best of our knowledge, this problem has not been addressed yet in the field of recommender system. The prediction of a movie genre has many practical applications including complementing the items categories given by experts and providing a surprise effect in the recommendations given to a user. We employ mulitnomial event model to estimate a likelihood of a movie given genre and the Bayes rule to evaluate the posterior probability of a genre given a movie. Experiments with the MovieLens dataset validate our approach. We achieved 70% prediction rate using only 15% of the whole set for training.
no_new_dataset
0.95222
1603.07879
Raja Kishor D Mr.
D. Raja Kishor, N. B. Venkateswarlu
Hybridization of Expectation-Maximization and K-Means Algorithms for Better Clustering Performance
17 pages, 18 figures
null
null
null
cs.LG stat.ML
http://creativecommons.org/licenses/by/4.0/
The present work proposes hybridization of Expectation-Maximization (EM) and K-Means techniques as an attempt to speed-up the clustering process. Though both K-Means and EM techniques look into different areas, K-means can be viewed as an approximate way to obtain maximum likelihood estimates for the means. Along with the proposed algorithm for hybridization, the present work also experiments with the Standard EM algorithm. Six different datasets are used for the experiments of which three are synthetic datasets. Clustering fitness and Sum of Squared Errors (SSE) are computed for measuring the clustering performance. In all the experiments it is observed that the proposed algorithm for hybridization of EM and K-Means techniques is consistently taking less execution time with acceptable Clustering Fitness value and less SSE than the standard EM algorithm. It is also observed that the proposed algorithm is producing better clustering results than the Cluster package of Purdue University.
[ { "version": "v1", "created": "Fri, 25 Mar 2016 11:09:22 GMT" } ]
2016-03-28T00:00:00
[ [ "Kishor", "D. Raja", "" ], [ "Venkateswarlu", "N. B.", "" ] ]
TITLE: Hybridization of Expectation-Maximization and K-Means Algorithms for Better Clustering Performance ABSTRACT: The present work proposes hybridization of Expectation-Maximization (EM) and K-Means techniques as an attempt to speed-up the clustering process. Though both K-Means and EM techniques look into different areas, K-means can be viewed as an approximate way to obtain maximum likelihood estimates for the means. Along with the proposed algorithm for hybridization, the present work also experiments with the Standard EM algorithm. Six different datasets are used for the experiments of which three are synthetic datasets. Clustering fitness and Sum of Squared Errors (SSE) are computed for measuring the clustering performance. In all the experiments it is observed that the proposed algorithm for hybridization of EM and K-Means techniques is consistently taking less execution time with acceptable Clustering Fitness value and less SSE than the standard EM algorithm. It is also observed that the proposed algorithm is producing better clustering results than the Cluster package of Purdue University.
no_new_dataset
0.951504
1603.07886
Shanlin Zhong
Peijie Yin, Hong Qiao, Wei Wu, Lu Qi, YinLin Li, Shanlin Zhong, Bo Zhang
A Novel Biologically Mechanism-Based Visual Cognition Model--Automatic Extraction of Semantics, Formation of Integrated Concepts and Re-selection Features for Ambiguity
null
null
null
null
cs.CV cs.AI cs.LG
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Integration between biology and information science benefits both fields. Many related models have been proposed, such as computational visual cognition models, computational motor control models, integrations of both and so on. In general, the robustness and precision of recognition is one of the key problems for object recognition models. In this paper, inspired by features of human recognition process and their biological mechanisms, a new integrated and dynamic framework is proposed to mimic the semantic extraction, concept formation and feature re-selection in human visual processing. The main contributions of the proposed model are as follows: (1) Semantic feature extraction: Local semantic features are learnt from episodic features that are extracted from raw images through a deep neural network; (2) Integrated concept formation: Concepts are formed with local semantic information and structural information learnt through network. (3) Feature re-selection: When ambiguity is detected during recognition process, distinctive features according to the difference between ambiguous candidates are re-selected for recognition. Experimental results on hand-written digits and facial shape dataset show that, compared with other methods, the new proposed model exhibits higher robustness and precision for visual recognition, especially in the condition when input samples are smantic ambiguous. Meanwhile, the introduced biological mechanisms further strengthen the interaction between neuroscience and information science.
[ { "version": "v1", "created": "Fri, 25 Mar 2016 11:47:16 GMT" } ]
2016-03-28T00:00:00
[ [ "Yin", "Peijie", "" ], [ "Qiao", "Hong", "" ], [ "Wu", "Wei", "" ], [ "Qi", "Lu", "" ], [ "Li", "YinLin", "" ], [ "Zhong", "Shanlin", "" ], [ "Zhang", "Bo", "" ] ]
TITLE: A Novel Biologically Mechanism-Based Visual Cognition Model--Automatic Extraction of Semantics, Formation of Integrated Concepts and Re-selection Features for Ambiguity ABSTRACT: Integration between biology and information science benefits both fields. Many related models have been proposed, such as computational visual cognition models, computational motor control models, integrations of both and so on. In general, the robustness and precision of recognition is one of the key problems for object recognition models. In this paper, inspired by features of human recognition process and their biological mechanisms, a new integrated and dynamic framework is proposed to mimic the semantic extraction, concept formation and feature re-selection in human visual processing. The main contributions of the proposed model are as follows: (1) Semantic feature extraction: Local semantic features are learnt from episodic features that are extracted from raw images through a deep neural network; (2) Integrated concept formation: Concepts are formed with local semantic information and structural information learnt through network. (3) Feature re-selection: When ambiguity is detected during recognition process, distinctive features according to the difference between ambiguous candidates are re-selected for recognition. Experimental results on hand-written digits and facial shape dataset show that, compared with other methods, the new proposed model exhibits higher robustness and precision for visual recognition, especially in the condition when input samples are smantic ambiguous. Meanwhile, the introduced biological mechanisms further strengthen the interaction between neuroscience and information science.
no_new_dataset
0.951369
1603.07980
Joseph Dulny III
Joseph Dulny III and Michael Kim
Developing Quantum Annealer Driven Data Discovery
null
null
null
null
quant-ph cs.LG
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Machine learning applications are limited by computational power. In this paper, we gain novel insights into the application of quantum annealing (QA) to machine learning (ML) through experiments in natural language processing (NLP), seizure prediction, and linear separability testing. These experiments are performed on QA simulators and early-stage commercial QA hardware and compared to an unprecedented number of traditional ML techniques. We extend QBoost, an early implementation of a binary classifier that utilizes a quantum annealer, via resampling and ensembling of predicted probabilities to produce a more robust class estimator. To determine the strengths and weaknesses of this approach, resampled QBoost (RQBoost) is tested across several datasets and compared to QBoost and traditional ML. We show and explain how QBoost in combination with a commercial QA device are unable to perfectly separate binary class data which is linearly separable via logistic regression with shrinkage. We further explore the performance of RQBoost in the space of NLP and seizure prediction and find QA-enabled ML using QBoost and RQBoost is outperformed by traditional techniques. Additionally, we provide a detailed discussion of algorithmic constraints and trade-offs imposed by the use of this QA hardware. Through these experiments, we provide unique insights into the state of quantum ML via boosting and the use of quantum annealing hardware that are valuable to institutions interested in applying QA to problems in ML and beyond.
[ { "version": "v1", "created": "Fri, 25 Mar 2016 18:36:33 GMT" } ]
2016-03-28T00:00:00
[ [ "Dulny", "Joseph", "III" ], [ "Kim", "Michael", "" ] ]
TITLE: Developing Quantum Annealer Driven Data Discovery ABSTRACT: Machine learning applications are limited by computational power. In this paper, we gain novel insights into the application of quantum annealing (QA) to machine learning (ML) through experiments in natural language processing (NLP), seizure prediction, and linear separability testing. These experiments are performed on QA simulators and early-stage commercial QA hardware and compared to an unprecedented number of traditional ML techniques. We extend QBoost, an early implementation of a binary classifier that utilizes a quantum annealer, via resampling and ensembling of predicted probabilities to produce a more robust class estimator. To determine the strengths and weaknesses of this approach, resampled QBoost (RQBoost) is tested across several datasets and compared to QBoost and traditional ML. We show and explain how QBoost in combination with a commercial QA device are unable to perfectly separate binary class data which is linearly separable via logistic regression with shrinkage. We further explore the performance of RQBoost in the space of NLP and seizure prediction and find QA-enabled ML using QBoost and RQBoost is outperformed by traditional techniques. Additionally, we provide a detailed discussion of algorithmic constraints and trade-offs imposed by the use of this QA hardware. Through these experiments, we provide unique insights into the state of quantum ML via boosting and the use of quantum annealing hardware that are valuable to institutions interested in applying QA to problems in ML and beyond.
no_new_dataset
0.942876
1603.07342
Arkadiusz Hypki Dr
Arkadiusz Hypki
BEANS - a software package for distributed Big Data analysis
14 pages, 6 figures, submitted to MNRAS, comments are welcome
null
null
null
astro-ph.IM cs.MS
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
BEANS software is a web based, easy to install and maintain, new tool to store and analyse data in a distributed way for a massive amount of data. It provides a clear interface for querying, filtering, aggregating, and plotting data from an arbitrary number of datasets. Its main purpose is to simplify the process of storing, examining and finding new relations in the so-called Big Data. Creation of BEANS software is an answer to the growing needs of the astronomical community to have a versatile tool to store, analyse and compare the complex astrophysical numerical simulations with observations (e.g. simulations of the Galaxy or star clusters with the Gaia archive). However, this software was built in a general form and it is ready to use in any other research field or open source software.
[ { "version": "v1", "created": "Wed, 23 Mar 2016 20:14:34 GMT" } ]
2016-03-25T00:00:00
[ [ "Hypki", "Arkadiusz", "" ] ]
TITLE: BEANS - a software package for distributed Big Data analysis ABSTRACT: BEANS software is a web based, easy to install and maintain, new tool to store and analyse data in a distributed way for a massive amount of data. It provides a clear interface for querying, filtering, aggregating, and plotting data from an arbitrary number of datasets. Its main purpose is to simplify the process of storing, examining and finding new relations in the so-called Big Data. Creation of BEANS software is an answer to the growing needs of the astronomical community to have a versatile tool to store, analyse and compare the complex astrophysical numerical simulations with observations (e.g. simulations of the Galaxy or star clusters with the Gaia archive). However, this software was built in a general form and it is ready to use in any other research field or open source software.
no_new_dataset
0.93852
1603.07376
Paolo Cintia
Paolo Cintia, Mirco Nanni
An effective Time-Aware Map Matching process for low sampling GPS data
null
null
null
null
cs.DS
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
In the era of the proliferation of Geo-Spatial Data, induced by the diffusion of GPS devices, the map matching problem still represents an important and valuable challenge. The process of associating a segment of the underlying road network to a GPS point gives us the chance to enrich raw data with the semantic layer provided by the roadmap, with all contextual information associated to it, e.g. the presence of speed limits, attraction points, changes in elevation, etc. Most state-of-art solutions for this classical problem simply look for the shortest or fastest path connecting any pair of consecutive points in a trip. While in some contexts that is reasonable, in this work we argue that the shortest/fastest path assumption can be in general erroneous. Indeed, we show that such approaches can yield travel times that are significantly incoherent with the real ones, and propose a Time-Aware Map matching process that tries to improve the state-of-art by taking into account also such temporal aspect. Our algorithm results to be very efficient, effective on low- sampling data and to outperform existing solutions, as proved by experiments on large datasets of real GPS trajectories. Moreover, our algorithm is parameter-free and does not depend on specific characteristics of the GPS localization error and of the road network (e.g. density of roads, road network topology, etc.).
[ { "version": "v1", "created": "Wed, 23 Mar 2016 21:48:38 GMT" } ]
2016-03-25T00:00:00
[ [ "Cintia", "Paolo", "" ], [ "Nanni", "Mirco", "" ] ]
TITLE: An effective Time-Aware Map Matching process for low sampling GPS data ABSTRACT: In the era of the proliferation of Geo-Spatial Data, induced by the diffusion of GPS devices, the map matching problem still represents an important and valuable challenge. The process of associating a segment of the underlying road network to a GPS point gives us the chance to enrich raw data with the semantic layer provided by the roadmap, with all contextual information associated to it, e.g. the presence of speed limits, attraction points, changes in elevation, etc. Most state-of-art solutions for this classical problem simply look for the shortest or fastest path connecting any pair of consecutive points in a trip. While in some contexts that is reasonable, in this work we argue that the shortest/fastest path assumption can be in general erroneous. Indeed, we show that such approaches can yield travel times that are significantly incoherent with the real ones, and propose a Time-Aware Map matching process that tries to improve the state-of-art by taking into account also such temporal aspect. Our algorithm results to be very efficient, effective on low- sampling data and to outperform existing solutions, as proved by experiments on large datasets of real GPS trajectories. Moreover, our algorithm is parameter-free and does not depend on specific characteristics of the GPS localization error and of the road network (e.g. density of roads, road network topology, etc.).
no_new_dataset
0.947721
1603.07396
Aniruddha Kembhavi
Aniruddha Kembhavi, Mike Salvato, Eric Kolve, Minjoon Seo, Hannaneh Hajishirzi, Ali Farhadi
A Diagram Is Worth A Dozen Images
null
null
null
null
cs.CV cs.AI
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Diagrams are common tools for representing complex concepts, relationships and events, often when it would be difficult to portray the same information with natural images. Understanding natural images has been extensively studied in computer vision, while diagram understanding has received little attention. In this paper, we study the problem of diagram interpretation and reasoning, the challenging task of identifying the structure of a diagram and the semantics of its constituents and their relationships. We introduce Diagram Parse Graphs (DPG) as our representation to model the structure of diagrams. We define syntactic parsing of diagrams as learning to infer DPGs for diagrams and study semantic interpretation and reasoning of diagrams in the context of diagram question answering. We devise an LSTM-based method for syntactic parsing of diagrams and introduce a DPG-based attention model for diagram question answering. We compile a new dataset of diagrams with exhaustive annotations of constituents and relationships for over 5,000 diagrams and 15,000 questions and answers. Our results show the significance of our models for syntactic parsing and question answering in diagrams using DPGs.
[ { "version": "v1", "created": "Thu, 24 Mar 2016 00:02:58 GMT" } ]
2016-03-25T00:00:00
[ [ "Kembhavi", "Aniruddha", "" ], [ "Salvato", "Mike", "" ], [ "Kolve", "Eric", "" ], [ "Seo", "Minjoon", "" ], [ "Hajishirzi", "Hannaneh", "" ], [ "Farhadi", "Ali", "" ] ]
TITLE: A Diagram Is Worth A Dozen Images ABSTRACT: Diagrams are common tools for representing complex concepts, relationships and events, often when it would be difficult to portray the same information with natural images. Understanding natural images has been extensively studied in computer vision, while diagram understanding has received little attention. In this paper, we study the problem of diagram interpretation and reasoning, the challenging task of identifying the structure of a diagram and the semantics of its constituents and their relationships. We introduce Diagram Parse Graphs (DPG) as our representation to model the structure of diagrams. We define syntactic parsing of diagrams as learning to infer DPGs for diagrams and study semantic interpretation and reasoning of diagrams in the context of diagram question answering. We devise an LSTM-based method for syntactic parsing of diagrams and introduce a DPG-based attention model for diagram question answering. We compile a new dataset of diagrams with exhaustive annotations of constituents and relationships for over 5,000 diagrams and 15,000 questions and answers. Our results show the significance of our models for syntactic parsing and question answering in diagrams using DPGs.
new_dataset
0.958731
1603.07433
Shouhuai Xu
Zhenxin Zhan and Maochao Xu and Shouhuai Xu
Characterizing Honeypot-Captured Cyber Attacks: Statistical Framework and Case Study
null
IEEE Transactions on Information Forensics & Security (IEEE TIFS), 8(11): 1775-1789, (2013)
null
null
cs.CR stat.AP
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Rigorously characterizing the statistical properties of cyber attacks is an important problem. In this paper, we propose the {\em first} statistical framework for rigorously analyzing honeypot-captured cyber attack data. The framework is built on the novel concept of {\em stochastic cyber attack process}, a new kind of mathematical objects for describing cyber attacks. To demonstrate use of the framework, we apply it to analyze a low-interaction honeypot dataset, while noting that the framework can be equally applied to analyze high-interaction honeypot data that contains richer information about the attacks. The case study finds, for the first time, that Long-Range Dependence (LRD) is exhibited by honeypot-captured cyber attacks. The case study confirms that by exploiting the statistical properties (LRD in this case), it is feasible to predict cyber attacks (at least in terms of attack rate) with good accuracy. This kind of prediction capability would provide sufficient early-warning time for defenders to adjust their defense configurations or resource allocations. The idea of "gray-box" (rather than "black-box") prediction is central to the utility of the statistical framework, and represents a significant step towards ultimately understanding (the degree of) the {\em predictability} of cyber attacks.
[ { "version": "v1", "created": "Thu, 24 Mar 2016 04:27:09 GMT" } ]
2016-03-25T00:00:00
[ [ "Zhan", "Zhenxin", "" ], [ "Xu", "Maochao", "" ], [ "Xu", "Shouhuai", "" ] ]
TITLE: Characterizing Honeypot-Captured Cyber Attacks: Statistical Framework and Case Study ABSTRACT: Rigorously characterizing the statistical properties of cyber attacks is an important problem. In this paper, we propose the {\em first} statistical framework for rigorously analyzing honeypot-captured cyber attack data. The framework is built on the novel concept of {\em stochastic cyber attack process}, a new kind of mathematical objects for describing cyber attacks. To demonstrate use of the framework, we apply it to analyze a low-interaction honeypot dataset, while noting that the framework can be equally applied to analyze high-interaction honeypot data that contains richer information about the attacks. The case study finds, for the first time, that Long-Range Dependence (LRD) is exhibited by honeypot-captured cyber attacks. The case study confirms that by exploiting the statistical properties (LRD in this case), it is feasible to predict cyber attacks (at least in terms of attack rate) with good accuracy. This kind of prediction capability would provide sufficient early-warning time for defenders to adjust their defense configurations or resource allocations. The idea of "gray-box" (rather than "black-box") prediction is central to the utility of the statistical framework, and represents a significant step towards ultimately understanding (the degree of) the {\em predictability} of cyber attacks.
no_new_dataset
0.949856
1603.07463
Olivier Delestre
Morgan Abily (I-CiTy), Olivier Delestre (JAD), Laura Amoss\'e, Nathalie Bertrand (IRSN), Christian Laguerre (MAPMO), Claire-Marie Duluc (IRSN), Philippe Gourbesville (I-CiTy)
Use of 3D classified topographic data with FullSWOF for high resolution simulation of a river flood event over a dense urban area
3rd IAHR Europe Congress, 14-16 April 2014, Porto, Portugal, Apr 2014, Porto, Portugal. 2016
null
null
null
math.NA cs.CE math.AP
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
High resolution (infra-metric) topographic data, including photogram-metric born 3D classified data, are becoming commonly available at large range of spatial extend, such as municipality or industrial site scale. This category of dataset is promising for high resolution (HR) Digital Surface Model (DSM) generation, allowing inclusion of fine above-ground structures which might influence overland flow hydrodynamic in urban environment. Nonetheless several categories of technical and numerical challenges arise from this type of data use with standard 2D Shallow Water Equations (SWE) based numerical codes. FullSWOF (Full Shallow Water equations for Overland Flow) is a code based on 2D SWE under conservative form. This code relies on a well-balanced finite volume method over a regular grid using numerical method based on hydrostatic reconstruction scheme. When compared to existing industrial codes used for urban flooding simulations, numerical approach implemented in FullSWOF allows to handle properly flow regime changes, preservation of water depth positivity at wet/dry cells transitions and steady state preservation. FullSWOF has already been tested on analytical solution library (SWASHES) and has been used to simulate runoff and dam-breaks. FullSWOFs above mentioned properties are of good interest for urban overland flow. Objectives of this study are (i) to assess the feasibility and added values of using HR 3D classified topographic data to model river overland flow and (ii) to take advantage of FullSWOF code properties for overland flow simulation in urban environment.
[ { "version": "v1", "created": "Thu, 24 Mar 2016 07:59:15 GMT" } ]
2016-03-25T00:00:00
[ [ "Abily", "Morgan", "", "I-CiTy" ], [ "Delestre", "Olivier", "", "JAD" ], [ "Amossé", "Laura", "", "IRSN" ], [ "Bertrand", "Nathalie", "", "IRSN" ], [ "Laguerre", "Christian", "", "MAPMO" ], [ "Duluc", "Claire-Marie", "", "IRSN" ], [ "Gourbesville", "Philippe", "", "I-CiTy" ] ]
TITLE: Use of 3D classified topographic data with FullSWOF for high resolution simulation of a river flood event over a dense urban area ABSTRACT: High resolution (infra-metric) topographic data, including photogram-metric born 3D classified data, are becoming commonly available at large range of spatial extend, such as municipality or industrial site scale. This category of dataset is promising for high resolution (HR) Digital Surface Model (DSM) generation, allowing inclusion of fine above-ground structures which might influence overland flow hydrodynamic in urban environment. Nonetheless several categories of technical and numerical challenges arise from this type of data use with standard 2D Shallow Water Equations (SWE) based numerical codes. FullSWOF (Full Shallow Water equations for Overland Flow) is a code based on 2D SWE under conservative form. This code relies on a well-balanced finite volume method over a regular grid using numerical method based on hydrostatic reconstruction scheme. When compared to existing industrial codes used for urban flooding simulations, numerical approach implemented in FullSWOF allows to handle properly flow regime changes, preservation of water depth positivity at wet/dry cells transitions and steady state preservation. FullSWOF has already been tested on analytical solution library (SWASHES) and has been used to simulate runoff and dam-breaks. FullSWOFs above mentioned properties are of good interest for urban overland flow. Objectives of this study are (i) to assess the feasibility and added values of using HR 3D classified topographic data to model river overland flow and (ii) to take advantage of FullSWOF code properties for overland flow simulation in urban environment.
no_new_dataset
0.949012
1603.07466
Marlon Dumas
Diego Calvanese, Marlon Dumas, \"Ulari Laurson, Fabrizio M. Maggi, Marco Montali, Irene Teinemaa
Semantics and Analysis of DMN Decision Tables
Submitted to the International Conference on Business Process Management (BPM 2016)
null
null
null
cs.SE
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The Decision Model and Notation (DMN) is a standard notation to capture decision logic in business applications in general and business processes in particular. A central construct in DMN is that of a decision table. The increasing use of DMN decision tables to capture critical business knowledge raises the need to support analysis tasks on these tables such as correctness and completeness checking. This paper provides a formal semantics for DMN tables, a formal definition of key analysis tasks and scalable algorithms to tackle two such tasks, i.e., detection of overlapping rules and of missing rules. The algorithms are based on a geometric interpretation of decision tables that can be used to support other analysis tasks by tapping into geometric algorithms. The algorithms have been implemented in an open-source DMN editor and tested on large decision tables derived from a credit lending dataset.
[ { "version": "v1", "created": "Thu, 24 Mar 2016 08:22:36 GMT" } ]
2016-03-25T00:00:00
[ [ "Calvanese", "Diego", "" ], [ "Dumas", "Marlon", "" ], [ "Laurson", "Ülari", "" ], [ "Maggi", "Fabrizio M.", "" ], [ "Montali", "Marco", "" ], [ "Teinemaa", "Irene", "" ] ]
TITLE: Semantics and Analysis of DMN Decision Tables ABSTRACT: The Decision Model and Notation (DMN) is a standard notation to capture decision logic in business applications in general and business processes in particular. A central construct in DMN is that of a decision table. The increasing use of DMN decision tables to capture critical business knowledge raises the need to support analysis tasks on these tables such as correctness and completeness checking. This paper provides a formal semantics for DMN tables, a formal definition of key analysis tasks and scalable algorithms to tackle two such tasks, i.e., detection of overlapping rules and of missing rules. The algorithms are based on a geometric interpretation of decision tables that can be used to support other analysis tasks by tapping into geometric algorithms. The algorithms have been implemented in an open-source DMN editor and tested on large decision tables derived from a credit lending dataset.
no_new_dataset
0.944587
1603.07475
Youngjin Yoon
Youngjin Yoon, Gyeongmin Choe, Namil Kim, Joon-Young Lee, In So Kweon
Fine-scale Surface Normal Estimation using a Single NIR Image
null
null
null
null
cs.CV
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We present surface normal estimation using a single near infrared (NIR) image. We are focusing on fine-scale surface geometry captured with an uncalibrated light source. To tackle this ill-posed problem, we adopt a generative adversarial network which is effective in recovering a sharp output, which is also essential for fine-scale surface normal estimation. We incorporate angular error and integrability constraint into the objective function of the network to make estimated normals physically meaningful. We train and validate our network on a recent NIR dataset, and also evaluate the generality of our trained model by using new external datasets which are captured with a different camera under different environment.
[ { "version": "v1", "created": "Thu, 24 Mar 2016 08:43:14 GMT" } ]
2016-03-25T00:00:00
[ [ "Yoon", "Youngjin", "" ], [ "Choe", "Gyeongmin", "" ], [ "Kim", "Namil", "" ], [ "Lee", "Joon-Young", "" ], [ "Kweon", "In So", "" ] ]
TITLE: Fine-scale Surface Normal Estimation using a Single NIR Image ABSTRACT: We present surface normal estimation using a single near infrared (NIR) image. We are focusing on fine-scale surface geometry captured with an uncalibrated light source. To tackle this ill-posed problem, we adopt a generative adversarial network which is effective in recovering a sharp output, which is also essential for fine-scale surface normal estimation. We incorporate angular error and integrability constraint into the objective function of the network to make estimated normals physically meaningful. We train and validate our network on a recent NIR dataset, and also evaluate the generality of our trained model by using new external datasets which are captured with a different camera under different environment.
no_new_dataset
0.878991
1603.07646
Saurabh Kataria
Saurabh Kataria
Recursive Neural Language Architecture for Tag Prediction
null
null
null
null
cs.IR cs.CL cs.LG cs.NE
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We consider the problem of learning distributed representations for tags from their associated content for the task of tag recommendation. Considering tagging information is usually very sparse, effective learning from content and tag association is very crucial and challenging task. Recently, various neural representation learning models such as WSABIE and its variants show promising performance, mainly due to compact feature representations learned in a semantic space. However, their capacity is limited by a linear compositional approach for representing tags as sum of equal parts and hurt their performance. In this work, we propose a neural feedback relevance model for learning tag representations with weighted feature representations. Our experiments on two widely used datasets show significant improvement for quality of recommendations over various baselines.
[ { "version": "v1", "created": "Thu, 24 Mar 2016 16:39:37 GMT" } ]
2016-03-25T00:00:00
[ [ "Kataria", "Saurabh", "" ] ]
TITLE: Recursive Neural Language Architecture for Tag Prediction ABSTRACT: We consider the problem of learning distributed representations for tags from their associated content for the task of tag recommendation. Considering tagging information is usually very sparse, effective learning from content and tag association is very crucial and challenging task. Recently, various neural representation learning models such as WSABIE and its variants show promising performance, mainly due to compact feature representations learned in a semantic space. However, their capacity is limited by a linear compositional approach for representing tags as sum of equal parts and hurt their performance. In this work, we propose a neural feedback relevance model for learning tag representations with weighted feature representations. Our experiments on two widely used datasets show significant improvement for quality of recommendations over various baselines.
no_new_dataset
0.944382
1412.0722
Stuart Hamilton
Stuart Hamilton and Daniel Casey
Creation of a high spatiotemporal resolution global database of continuous mangrove forest cover for the 21st Century (CGMFC-21)
31 pages, 3 tables, 1 Figure
null
10.1111/geb.12449
null
physics.geo-ph physics.ao-ph
http://creativecommons.org/licenses/by-nc-sa/4.0/
The goal of this research is to provide high resolution local, regional, national and global estimates of annual mangrove forest area from 2000 through to 2012. To achieve this we synthesize the Global Forest Change database, the Terrestrial Ecosystems of the World database, and the Mangrove Forests of the World database to extract mangrove forest cover at high spatial and temporal resolutions. We then use the new database to monitor mangrove cover at the global, national and protected area scales. Countries showing relatively high amounts of mangrove loss include Myanmar, Malaysia, Cambodia, Indonesia, and Guatemala. Indonesia remains by far the largest mangrove-holding nation, containing between 26 percent and 29 percent of the global mangrove inventory with a deforestation rate of between 0.26 percent and 0.66 percent annually. Global mangrove deforestation continues but at a much reduced rate of between 0.16 percent and 0.39 percent annually. Southeast Asia is a region of concern with mangrove deforestation rates between 3.58 percent and 8.08 percent during the analysis period, this in a region containing half of the entire global mangrove forest inventory. The global mangrove deforestation pattern from 2000 to 2012 is one of decreasing rates of deforestation, with many nations essentially stable, with the exception of the largest mangrove-holding region of Southeast Asia. We provide a standardized global spatial dataset that monitors mangrove deforestation globally at high spatiotemporal resolutions, covering 99 percent of all mangrove forests. These data can be used to drive the mangrove research agenda particularly as it pertains to improved monitoring of mangrove carbon stocks and the establishment of baseline local mangrove forest inventories required for payment for ecosystem service initiatives.
[ { "version": "v1", "created": "Mon, 1 Dec 2014 22:58:11 GMT" }, { "version": "v2", "created": "Sat, 5 Sep 2015 20:01:53 GMT" }, { "version": "v3", "created": "Wed, 6 Jan 2016 19:39:55 GMT" } ]
2016-03-24T00:00:00
[ [ "Hamilton", "Stuart", "" ], [ "Casey", "Daniel", "" ] ]
TITLE: Creation of a high spatiotemporal resolution global database of continuous mangrove forest cover for the 21st Century (CGMFC-21) ABSTRACT: The goal of this research is to provide high resolution local, regional, national and global estimates of annual mangrove forest area from 2000 through to 2012. To achieve this we synthesize the Global Forest Change database, the Terrestrial Ecosystems of the World database, and the Mangrove Forests of the World database to extract mangrove forest cover at high spatial and temporal resolutions. We then use the new database to monitor mangrove cover at the global, national and protected area scales. Countries showing relatively high amounts of mangrove loss include Myanmar, Malaysia, Cambodia, Indonesia, and Guatemala. Indonesia remains by far the largest mangrove-holding nation, containing between 26 percent and 29 percent of the global mangrove inventory with a deforestation rate of between 0.26 percent and 0.66 percent annually. Global mangrove deforestation continues but at a much reduced rate of between 0.16 percent and 0.39 percent annually. Southeast Asia is a region of concern with mangrove deforestation rates between 3.58 percent and 8.08 percent during the analysis period, this in a region containing half of the entire global mangrove forest inventory. The global mangrove deforestation pattern from 2000 to 2012 is one of decreasing rates of deforestation, with many nations essentially stable, with the exception of the largest mangrove-holding region of Southeast Asia. We provide a standardized global spatial dataset that monitors mangrove deforestation globally at high spatiotemporal resolutions, covering 99 percent of all mangrove forests. These data can be used to drive the mangrove research agenda particularly as it pertains to improved monitoring of mangrove carbon stocks and the establishment of baseline local mangrove forest inventories required for payment for ecosystem service initiatives.
no_new_dataset
0.766818
1601.03128
Anand Mishra Mr.
Anand Mishra and Karteek Alahari and C. V. Jawahar
Enhancing Energy Minimization Framework for Scene Text Recognition with Top-Down Cues
null
null
10.1016/j.cviu.2016.01.002
null
cs.CV
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Recognizing scene text is a challenging problem, even more so than the recognition of scanned documents. This problem has gained significant attention from the computer vision community in recent years, and several methods based on energy minimization frameworks and deep learning approaches have been proposed. In this work, we focus on the energy minimization framework and propose a model that exploits both bottom-up and top-down cues for recognizing cropped words extracted from street images. The bottom-up cues are derived from individual character detections from an image. We build a conditional random field model on these detections to jointly model the strength of the detections and the interactions between them. These interactions are top-down cues obtained from a lexicon-based prior, i.e., language statistics. The optimal word represented by the text image is obtained by minimizing the energy function corresponding to the random field model. We evaluate our proposed algorithm extensively on a number of cropped scene text benchmark datasets, namely Street View Text, ICDAR 2003, 2011 and 2013 datasets, and IIIT 5K-word, and show better performance than comparable methods. We perform a rigorous analysis of all the steps in our approach and analyze the results. We also show that state-of-the-art convolutional neural network features can be integrated in our framework to further improve the recognition performance.
[ { "version": "v1", "created": "Wed, 13 Jan 2016 04:47:28 GMT" } ]
2016-03-24T00:00:00
[ [ "Mishra", "Anand", "" ], [ "Alahari", "Karteek", "" ], [ "Jawahar", "C. V.", "" ] ]
TITLE: Enhancing Energy Minimization Framework for Scene Text Recognition with Top-Down Cues ABSTRACT: Recognizing scene text is a challenging problem, even more so than the recognition of scanned documents. This problem has gained significant attention from the computer vision community in recent years, and several methods based on energy minimization frameworks and deep learning approaches have been proposed. In this work, we focus on the energy minimization framework and propose a model that exploits both bottom-up and top-down cues for recognizing cropped words extracted from street images. The bottom-up cues are derived from individual character detections from an image. We build a conditional random field model on these detections to jointly model the strength of the detections and the interactions between them. These interactions are top-down cues obtained from a lexicon-based prior, i.e., language statistics. The optimal word represented by the text image is obtained by minimizing the energy function corresponding to the random field model. We evaluate our proposed algorithm extensively on a number of cropped scene text benchmark datasets, namely Street View Text, ICDAR 2003, 2011 and 2013 datasets, and IIIT 5K-word, and show better performance than comparable methods. We perform a rigorous analysis of all the steps in our approach and analyze the results. We also show that state-of-the-art convolutional neural network features can be integrated in our framework to further improve the recognition performance.
no_new_dataset
0.950824
1603.07022
Alberto Pretto
Marco Imperoli and Alberto Pretto
Active Detection and Localization of Textureless Objects in Cluttered Environments
null
null
null
null
cs.CV cs.RO
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
This paper introduces an active object detection and localization framework that combines a robust untextured object detection and 3D pose estimation algorithm with a novel next-best-view selection strategy. We address the detection and localization problems by proposing an edge-based registration algorithm that refines the object position by minimizing a cost directly extracted from a 3D image tensor that encodes the minimum distance to an edge point in a joint direction/location space. We face the next-best-view problem by exploiting a sequential decision process that, for each step, selects the next camera position which maximizes the mutual information between the state and the next observations. We solve the intrinsic intractability of this solution by generating observations that represent scene realizations, i.e. combination samples of object hypothesis provided by the object detector, while modeling the state by means of a set of constantly resampled particles. Experiments performed on different real world, challenging datasets confirm the effectiveness of the proposed methods.
[ { "version": "v1", "created": "Tue, 22 Mar 2016 22:55:03 GMT" } ]
2016-03-24T00:00:00
[ [ "Imperoli", "Marco", "" ], [ "Pretto", "Alberto", "" ] ]
TITLE: Active Detection and Localization of Textureless Objects in Cluttered Environments ABSTRACT: This paper introduces an active object detection and localization framework that combines a robust untextured object detection and 3D pose estimation algorithm with a novel next-best-view selection strategy. We address the detection and localization problems by proposing an edge-based registration algorithm that refines the object position by minimizing a cost directly extracted from a 3D image tensor that encodes the minimum distance to an edge point in a joint direction/location space. We face the next-best-view problem by exploiting a sequential decision process that, for each step, selects the next camera position which maximizes the mutual information between the state and the next observations. We solve the intrinsic intractability of this solution by generating observations that represent scene realizations, i.e. combination samples of object hypothesis provided by the object detector, while modeling the state by means of a set of constantly resampled particles. Experiments performed on different real world, challenging datasets confirm the effectiveness of the proposed methods.
no_new_dataset
0.950041
1603.07063
Xiaodan Liang
Xiaodan Liang and Xiaohui Shen and Jiashi Feng and Liang Lin and Shuicheng Yan
Semantic Object Parsing with Graph LSTM
18 pages
null
null
null
cs.CV
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
By taking the semantic object parsing task as an exemplar application scenario, we propose the Graph Long Short-Term Memory (Graph LSTM) network, which is the generalization of LSTM from sequential data or multi-dimensional data to general graph-structured data. Particularly, instead of evenly and fixedly dividing an image to pixels or patches in existing multi-dimensional LSTM structures (e.g., Row, Grid and Diagonal LSTMs), we take each arbitrary-shaped superpixel as a semantically consistent node, and adaptively construct an undirected graph for each image, where the spatial relations of the superpixels are naturally used as edges. Constructed on such an adaptive graph topology, the Graph LSTM is more naturally aligned with the visual patterns in the image (e.g., object boundaries or appearance similarities) and provides a more economical information propagation route. Furthermore, for each optimization step over Graph LSTM, we propose to use a confidence-driven scheme to update the hidden and memory states of nodes progressively till all nodes are updated. In addition, for each node, the forgets gates are adaptively learned to capture different degrees of semantic correlation with neighboring nodes. Comprehensive evaluations on four diverse semantic object parsing datasets well demonstrate the significant superiority of our Graph LSTM over other state-of-the-art solutions.
[ { "version": "v1", "created": "Wed, 23 Mar 2016 03:31:02 GMT" } ]
2016-03-24T00:00:00
[ [ "Liang", "Xiaodan", "" ], [ "Shen", "Xiaohui", "" ], [ "Feng", "Jiashi", "" ], [ "Lin", "Liang", "" ], [ "Yan", "Shuicheng", "" ] ]
TITLE: Semantic Object Parsing with Graph LSTM ABSTRACT: By taking the semantic object parsing task as an exemplar application scenario, we propose the Graph Long Short-Term Memory (Graph LSTM) network, which is the generalization of LSTM from sequential data or multi-dimensional data to general graph-structured data. Particularly, instead of evenly and fixedly dividing an image to pixels or patches in existing multi-dimensional LSTM structures (e.g., Row, Grid and Diagonal LSTMs), we take each arbitrary-shaped superpixel as a semantically consistent node, and adaptively construct an undirected graph for each image, where the spatial relations of the superpixels are naturally used as edges. Constructed on such an adaptive graph topology, the Graph LSTM is more naturally aligned with the visual patterns in the image (e.g., object boundaries or appearance similarities) and provides a more economical information propagation route. Furthermore, for each optimization step over Graph LSTM, we propose to use a confidence-driven scheme to update the hidden and memory states of nodes progressively till all nodes are updated. In addition, for each node, the forgets gates are adaptively learned to capture different degrees of semantic correlation with neighboring nodes. Comprehensive evaluations on four diverse semantic object parsing datasets well demonstrate the significant superiority of our Graph LSTM over other state-of-the-art solutions.
no_new_dataset
0.951729
1603.07064
Saman Sarraf
Saman Sarraf, Mehdi Ostadhashem
Big Data Spark Solution for Functional Magnetic Resonance Imaging
4 pages, IEEE EMBS 2016 ORLANDO
null
null
null
cs.DC cs.CY
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Recently, Big Data applications have rapidly expanded into different industries. Healthcare is also one the industries willing to use big data platforms so that some big data analytics tools have been adopted in this field to some extent. Medical imaging which is a pillar in diagnostic healthcare deals with high volume of data collection and processing. A huge amount of 3D and 4D images are acquired in different forms and resolutions using a variety of medical imaging modalities. Preprocessing and analyzing imaging data is currently a long process and cost and time consuming. However, not many big data platforms have been provided or redesigned for medical imaging purposes because of some restrictions such as data format. In this paper, we designed, developed and successfully tested a new pipeline for medical imaging data (especially functional magnetic resonance imaging - fMRI) using Big Data Spark / PySpark platform on a single node which allows us to read and load imaging data, convert them to Resilient Distributed Datasets in order manipulate and perform in-memory data processing in parallel and convert final results to imaging format while the pipeline provides an option to store the results in other formats such as data frame. Using this new solution and pipeline, we repeated our previous works in which we extracted brain networks from fMRI data using template matching and sum of squared differences (SSD) method. The final results revealed our Spark (PySpark) based solution improved the performance (in terms of processing time) around 4 times on a single compared to the previous work developed in Python.
[ { "version": "v1", "created": "Wed, 23 Mar 2016 03:42:44 GMT" } ]
2016-03-24T00:00:00
[ [ "Sarraf", "Saman", "" ], [ "Ostadhashem", "Mehdi", "" ] ]
TITLE: Big Data Spark Solution for Functional Magnetic Resonance Imaging ABSTRACT: Recently, Big Data applications have rapidly expanded into different industries. Healthcare is also one the industries willing to use big data platforms so that some big data analytics tools have been adopted in this field to some extent. Medical imaging which is a pillar in diagnostic healthcare deals with high volume of data collection and processing. A huge amount of 3D and 4D images are acquired in different forms and resolutions using a variety of medical imaging modalities. Preprocessing and analyzing imaging data is currently a long process and cost and time consuming. However, not many big data platforms have been provided or redesigned for medical imaging purposes because of some restrictions such as data format. In this paper, we designed, developed and successfully tested a new pipeline for medical imaging data (especially functional magnetic resonance imaging - fMRI) using Big Data Spark / PySpark platform on a single node which allows us to read and load imaging data, convert them to Resilient Distributed Datasets in order manipulate and perform in-memory data processing in parallel and convert final results to imaging format while the pipeline provides an option to store the results in other formats such as data frame. Using this new solution and pipeline, we repeated our previous works in which we extracted brain networks from fMRI data using template matching and sum of squared differences (SSD) method. The final results revealed our Spark (PySpark) based solution improved the performance (in terms of processing time) around 4 times on a single compared to the previous work developed in Python.
no_new_dataset
0.942082
1603.07094
Kai Morino
Motohide Higaki, Kai Morino, Hiroshi Murata, Ryo Asaoka, and Kenji Yamanishi
Predicting Glaucoma Visual Field Loss by Hierarchically Aggregating Clustering-based Predictors
null
null
null
null
stat.ML cs.LG
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
This study addresses the issue of predicting the glaucomatous visual field loss from patient disease datasets. Our goal is to accurately predict the progress of the disease in individual patients. As very few measurements are available for each patient, it is difficult to produce good predictors for individuals. A recently proposed clustering-based method enhances the power of prediction using patient data with similar spatiotemporal patterns. Each patient is categorized into a cluster of patients, and a predictive model is constructed using all of the data in the class. Predictions are highly dependent on the quality of clustering, but it is difficult to identify the best clustering method. Thus, we propose a method for aggregating cluster-based predictors to obtain better prediction accuracy than from a single cluster-based prediction. Further, the method shows very high performances by hierarchically aggregating experts generated from several cluster-based methods. We use real datasets to demonstrate that our method performs significantly better than conventional clustering-based and patient-wise regression methods, because the hierarchical aggregating strategy has a mechanism whereby good predictors in a small community can thrive.
[ { "version": "v1", "created": "Wed, 23 Mar 2016 09:06:19 GMT" } ]
2016-03-24T00:00:00
[ [ "Higaki", "Motohide", "" ], [ "Morino", "Kai", "" ], [ "Murata", "Hiroshi", "" ], [ "Asaoka", "Ryo", "" ], [ "Yamanishi", "Kenji", "" ] ]
TITLE: Predicting Glaucoma Visual Field Loss by Hierarchically Aggregating Clustering-based Predictors ABSTRACT: This study addresses the issue of predicting the glaucomatous visual field loss from patient disease datasets. Our goal is to accurately predict the progress of the disease in individual patients. As very few measurements are available for each patient, it is difficult to produce good predictors for individuals. A recently proposed clustering-based method enhances the power of prediction using patient data with similar spatiotemporal patterns. Each patient is categorized into a cluster of patients, and a predictive model is constructed using all of the data in the class. Predictions are highly dependent on the quality of clustering, but it is difficult to identify the best clustering method. Thus, we propose a method for aggregating cluster-based predictors to obtain better prediction accuracy than from a single cluster-based prediction. Further, the method shows very high performances by hierarchically aggregating experts generated from several cluster-based methods. We use real datasets to demonstrate that our method performs significantly better than conventional clustering-based and patient-wise regression methods, because the hierarchical aggregating strategy has a mechanism whereby good predictors in a small community can thrive.
no_new_dataset
0.94801
1603.07141
Francesc Moreno-Noguer
Arnau Ramisa, Fei Yan, Francesc Moreno-Noguer and Krystian Mikolajczyk
BreakingNews: Article Annotation by Image and Text Processing
null
null
null
null
cs.CV
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Building upon recent Deep Neural Network architectures, current approaches lying in the intersection of computer vision and natural language processing have achieved unprecedented breakthroughs in tasks like automatic captioning or image retrieval. Most of these learning methods, though, rely on large training sets of images associated with human annotations that specifically describe the visual content. In this paper we propose to go a step further and explore the more complex cases where textual descriptions are loosely related to the images. We focus on the particular domain of News articles in which the textual content often expresses connotative and ambiguous relations that are only suggested but not directly inferred from images. We introduce new deep learning methods that address source detection, popularity prediction, article illustration and geolocation of articles. An adaptive CNN architecture is proposed, that shares most of the structure for all the tasks, and is suitable for multitask and transfer learning. Deep Canonical Correlation Analysis is deployed for article illustration, and a new loss function based on Great Circle Distance is proposed for geolocation. Furthermore, we present BreakingNews, a novel dataset with approximately 100K news articles including images, text and captions, and enriched with heterogeneous meta-data (such as GPS coordinates and popularity metrics). We show this dataset to be appropriate to explore all aforementioned problems, for which we provide a baseline performance using various Deep Learning architectures, and different representations of the textual and visual features. We report very promising results and bring to light several limitations of current state-of-the-art in this kind of domain, which we hope will help spur progress in the field.
[ { "version": "v1", "created": "Wed, 23 Mar 2016 11:30:24 GMT" } ]
2016-03-24T00:00:00
[ [ "Ramisa", "Arnau", "" ], [ "Yan", "Fei", "" ], [ "Moreno-Noguer", "Francesc", "" ], [ "Mikolajczyk", "Krystian", "" ] ]
TITLE: BreakingNews: Article Annotation by Image and Text Processing ABSTRACT: Building upon recent Deep Neural Network architectures, current approaches lying in the intersection of computer vision and natural language processing have achieved unprecedented breakthroughs in tasks like automatic captioning or image retrieval. Most of these learning methods, though, rely on large training sets of images associated with human annotations that specifically describe the visual content. In this paper we propose to go a step further and explore the more complex cases where textual descriptions are loosely related to the images. We focus on the particular domain of News articles in which the textual content often expresses connotative and ambiguous relations that are only suggested but not directly inferred from images. We introduce new deep learning methods that address source detection, popularity prediction, article illustration and geolocation of articles. An adaptive CNN architecture is proposed, that shares most of the structure for all the tasks, and is suitable for multitask and transfer learning. Deep Canonical Correlation Analysis is deployed for article illustration, and a new loss function based on Great Circle Distance is proposed for geolocation. Furthermore, we present BreakingNews, a novel dataset with approximately 100K news articles including images, text and captions, and enriched with heterogeneous meta-data (such as GPS coordinates and popularity metrics). We show this dataset to be appropriate to explore all aforementioned problems, for which we provide a baseline performance using various Deep Learning architectures, and different representations of the textual and visual features. We report very promising results and bring to light several limitations of current state-of-the-art in this kind of domain, which we hope will help spur progress in the field.
new_dataset
0.965086
1603.07173
Veronica Morfi
Veronica Morfi, Dan Stowell
Deductive Refinement of Species Labelling in Weakly Labelled Birdsong Recordings
11 pages, 1 figure
null
null
null
cs.SD
http://creativecommons.org/licenses/by/4.0/
Many approaches have been used in bird species classification from their sound in order to provide labels for the whole of a recording. However, a more precise classification of each bird vocalization would be of great importance to the use and management of sound archives and bird monitoring. In this work, we introduce a technique that using a two step process can first automatically detect all bird vocalizations and then, with the use of 'weakly' labelled recordings, classify them. Evaluations of our proposed method show that it achieves a correct classification of 61% when used in a synthetic dataset, and up to 89% when the synthetic dataset only consists of vocalizations larger than 1000 pixels.
[ { "version": "v1", "created": "Wed, 23 Mar 2016 13:21:12 GMT" } ]
2016-03-24T00:00:00
[ [ "Morfi", "Veronica", "" ], [ "Stowell", "Dan", "" ] ]
TITLE: Deductive Refinement of Species Labelling in Weakly Labelled Birdsong Recordings ABSTRACT: Many approaches have been used in bird species classification from their sound in order to provide labels for the whole of a recording. However, a more precise classification of each bird vocalization would be of great importance to the use and management of sound archives and bird monitoring. In this work, we introduce a technique that using a two step process can first automatically detect all bird vocalizations and then, with the use of 'weakly' labelled recordings, classify them. Evaluations of our proposed method show that it achieves a correct classification of 61% when used in a synthetic dataset, and up to 89% when the synthetic dataset only consists of vocalizations larger than 1000 pixels.
no_new_dataset
0.943556
1603.07234
Rahaf Aljundi
Rahaf Aljundi and Tinne Tuytelaars
Lightweight Unsupervised Domain Adaptation by Convolutional Filter Reconstruction
null
null
null
null
cs.CV
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
End-to-end learning methods have achieved impressive results in many areas of computer vision. At the same time, these methods still suffer from a degradation in performance when testing on new datasets that stem from a different distribution. This is known as the domain shift effect. Recently proposed adaptation methods focus on retraining the network parameters. However, this requires access to all (labeled) source data, a large amount of (unlabeled) target data, and plenty of computational resources. In this work, we propose a lightweight alternative, that allows adapting to the target domain based on a limited number of target samples in a matter of minutes rather than hours, days or even weeks. To this end, we first analyze the output of each convolutional layer from a domain adaptation perspective. Surprisingly, we find that already at the very first layer, domain shift effects pop up. We then propose a new domain adaptation method, where first layer convolutional filters that are badly affected by the domain shift are reconstructed based on less affected ones. This improves the performance of the deep network on various benchmark datasets.
[ { "version": "v1", "created": "Wed, 23 Mar 2016 15:28:29 GMT" } ]
2016-03-24T00:00:00
[ [ "Aljundi", "Rahaf", "" ], [ "Tuytelaars", "Tinne", "" ] ]
TITLE: Lightweight Unsupervised Domain Adaptation by Convolutional Filter Reconstruction ABSTRACT: End-to-end learning methods have achieved impressive results in many areas of computer vision. At the same time, these methods still suffer from a degradation in performance when testing on new datasets that stem from a different distribution. This is known as the domain shift effect. Recently proposed adaptation methods focus on retraining the network parameters. However, this requires access to all (labeled) source data, a large amount of (unlabeled) target data, and plenty of computational resources. In this work, we propose a lightweight alternative, that allows adapting to the target domain based on a limited number of target samples in a matter of minutes rather than hours, days or even weeks. To this end, we first analyze the output of each convolutional layer from a domain adaptation perspective. Surprisingly, we find that already at the very first layer, domain shift effects pop up. We then propose a new domain adaptation method, where first layer convolutional filters that are badly affected by the domain shift are reconstructed based on less affected ones. This improves the performance of the deep network on various benchmark datasets.
no_new_dataset
0.949012
1507.02264
Scott Dawson
Scott T. M. Dawson, Maziar S. Hemati, Matthew O. Williams, Clarence W. Rowley
Characterizing and correcting for the effect of sensor noise in the dynamic mode decomposition
null
null
10.1007/s00348-016-2127-7
null
physics.flu-dyn
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Dynamic mode decomposition (DMD) provides a practical means of extracting insightful dynamical information from fluids datasets. Like any data processing technique, DMD's usefulness is limited by its ability to extract real and accurate dynamical features from noise-corrupted data. Here we show analytically that DMD is biased to sensor noise, and quantify how this bias depends on the size and noise level of the data. We present three modifications to DMD that can be used to remove this bias: (i) a direct correction of the identified bias using known noise properties, (ii) combining the results of performing DMD forwards and backwards in time, and (iii) a total least-squares-inspired algorithm. We discuss the relative merits of each algorithm, and demonstrate the performance of these modifications on a range of synthetic, numerical, and experimental datasets. We further compare our modified DMD algorithms with other variants proposed in recent literature.
[ { "version": "v1", "created": "Wed, 8 Jul 2015 19:24:10 GMT" }, { "version": "v2", "created": "Mon, 31 Aug 2015 17:19:58 GMT" }, { "version": "v3", "created": "Tue, 19 Jan 2016 00:39:42 GMT" } ]
2016-03-23T00:00:00
[ [ "Dawson", "Scott T. M.", "" ], [ "Hemati", "Maziar S.", "" ], [ "Williams", "Matthew O.", "" ], [ "Rowley", "Clarence W.", "" ] ]
TITLE: Characterizing and correcting for the effect of sensor noise in the dynamic mode decomposition ABSTRACT: Dynamic mode decomposition (DMD) provides a practical means of extracting insightful dynamical information from fluids datasets. Like any data processing technique, DMD's usefulness is limited by its ability to extract real and accurate dynamical features from noise-corrupted data. Here we show analytically that DMD is biased to sensor noise, and quantify how this bias depends on the size and noise level of the data. We present three modifications to DMD that can be used to remove this bias: (i) a direct correction of the identified bias using known noise properties, (ii) combining the results of performing DMD forwards and backwards in time, and (iii) a total least-squares-inspired algorithm. We discuss the relative merits of each algorithm, and demonstrate the performance of these modifications on a range of synthetic, numerical, and experimental datasets. We further compare our modified DMD algorithms with other variants proposed in recent literature.
no_new_dataset
0.946646
1512.01881
Min Sun
Cheng-Sheng Chan, Shou-Zhong Chen, Pei-Xuan Xie, Chiung-Chih Chang, Min Sun
Recognition from Hand Cameras
null
null
null
null
cs.CV
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We revisit the study of a wrist-mounted camera system (referred to as HandCam) for recognizing activities of hands. HandCam has two unique properties as compared to egocentric systems (referred to as HeadCam): (1) it avoids the need to detect hands; (2) it more consistently observes the activities of hands. By taking advantage of these properties, we propose a deep-learning-based method to recognize hand states (free v.s. active hands, hand gestures, object categories), and discover object categories. Moreover, we propose a novel two-streams deep network to further take advantage of both HandCam and HeadCam. We have collected a new synchronized HandCam and HeadCam dataset with 20 videos captured in three scenes for hand states recognition. Experiments show that our HandCam system consistently outperforms a deep-learning-based HeadCam method (with estimated manipulation regions) and a dense-trajectory-based HeadCam method in all tasks. We also show that HandCam videos captured by different users can be easily aligned to improve free v.s. active recognition accuracy (3.3% improvement) in across-scenes use case. Moreover, we observe that finetuning Convolutional Neural Network consistently improves accuracy. Finally, our novel two-streams deep network combining HandCam and HeadCam features achieves the best performance in four out of five tasks. With more data, we believe a joint HandCam and HeadCam system can robustly log hand states in daily life.
[ { "version": "v1", "created": "Mon, 7 Dec 2015 02:06:29 GMT" }, { "version": "v2", "created": "Fri, 11 Dec 2015 16:04:40 GMT" }, { "version": "v3", "created": "Tue, 22 Mar 2016 09:12:04 GMT" } ]
2016-03-23T00:00:00
[ [ "Chan", "Cheng-Sheng", "" ], [ "Chen", "Shou-Zhong", "" ], [ "Xie", "Pei-Xuan", "" ], [ "Chang", "Chiung-Chih", "" ], [ "Sun", "Min", "" ] ]
TITLE: Recognition from Hand Cameras ABSTRACT: We revisit the study of a wrist-mounted camera system (referred to as HandCam) for recognizing activities of hands. HandCam has two unique properties as compared to egocentric systems (referred to as HeadCam): (1) it avoids the need to detect hands; (2) it more consistently observes the activities of hands. By taking advantage of these properties, we propose a deep-learning-based method to recognize hand states (free v.s. active hands, hand gestures, object categories), and discover object categories. Moreover, we propose a novel two-streams deep network to further take advantage of both HandCam and HeadCam. We have collected a new synchronized HandCam and HeadCam dataset with 20 videos captured in three scenes for hand states recognition. Experiments show that our HandCam system consistently outperforms a deep-learning-based HeadCam method (with estimated manipulation regions) and a dense-trajectory-based HeadCam method in all tasks. We also show that HandCam videos captured by different users can be easily aligned to improve free v.s. active recognition accuracy (3.3% improvement) in across-scenes use case. Moreover, we observe that finetuning Convolutional Neural Network consistently improves accuracy. Finally, our novel two-streams deep network combining HandCam and HeadCam features achieves the best performance in four out of five tasks. With more data, we believe a joint HandCam and HeadCam system can robustly log hand states in daily life.
new_dataset
0.956917
1512.06110
Manaal Faruqui
Manaal Faruqui and Yulia Tsvetkov and Graham Neubig and Chris Dyer
Morphological Inflection Generation Using Character Sequence to Sequence Learning
Proceedings of NAACL 2016
null
null
null
cs.CL
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Morphological inflection generation is the task of generating the inflected form of a given lemma corresponding to a particular linguistic transformation. We model the problem of inflection generation as a character sequence to sequence learning problem and present a variant of the neural encoder-decoder model for solving it. Our model is language independent and can be trained in both supervised and semi-supervised settings. We evaluate our system on seven datasets of morphologically rich languages and achieve either better or comparable results to existing state-of-the-art models of inflection generation.
[ { "version": "v1", "created": "Fri, 18 Dec 2015 20:48:26 GMT" }, { "version": "v2", "created": "Thu, 31 Dec 2015 17:23:32 GMT" }, { "version": "v3", "created": "Tue, 22 Mar 2016 01:02:01 GMT" } ]
2016-03-23T00:00:00
[ [ "Faruqui", "Manaal", "" ], [ "Tsvetkov", "Yulia", "" ], [ "Neubig", "Graham", "" ], [ "Dyer", "Chris", "" ] ]
TITLE: Morphological Inflection Generation Using Character Sequence to Sequence Learning ABSTRACT: Morphological inflection generation is the task of generating the inflected form of a given lemma corresponding to a particular linguistic transformation. We model the problem of inflection generation as a character sequence to sequence learning problem and present a variant of the neural encoder-decoder model for solving it. Our model is language independent and can be trained in both supervised and semi-supervised settings. We evaluate our system on seven datasets of morphologically rich languages and achieve either better or comparable results to existing state-of-the-art models of inflection generation.
no_new_dataset
0.954942
1601.01651
Antonino Miceli
Daikang Yan, Thomas Cecil, Lisa Gades, Chris Jacobsen, Timothy Madden, Antonino Miceli
Processing of X-ray Microcalorimeter Data with Pulse Shape Variation using Principal Component Analysis
Accepted for publication in J. Low Temperature Physics, Low Temperature Detectors 16 (LTD-16) conference
null
10.1007/s10909-016-1480-5
null
physics.ins-det astro-ph.IM physics.data-an
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We present a method using principal component analysis (PCA) to process x-ray pulses with severe shape variation where traditional optimal filter methods fail. We demonstrate that PCA is able to noise-filter and extract energy information from x-ray pulses despite their different shapes. We apply this method to a dataset from an x-ray thermal kinetic inductance detector which has severe pulse shape variation arising from position-dependent absorption.
[ { "version": "v1", "created": "Thu, 7 Jan 2016 20:00:01 GMT" } ]
2016-03-23T00:00:00
[ [ "Yan", "Daikang", "" ], [ "Cecil", "Thomas", "" ], [ "Gades", "Lisa", "" ], [ "Jacobsen", "Chris", "" ], [ "Madden", "Timothy", "" ], [ "Miceli", "Antonino", "" ] ]
TITLE: Processing of X-ray Microcalorimeter Data with Pulse Shape Variation using Principal Component Analysis ABSTRACT: We present a method using principal component analysis (PCA) to process x-ray pulses with severe shape variation where traditional optimal filter methods fail. We demonstrate that PCA is able to noise-filter and extract energy information from x-ray pulses despite their different shapes. We apply this method to a dataset from an x-ray thermal kinetic inductance detector which has severe pulse shape variation arising from position-dependent absorption.
no_new_dataset
0.954478
1603.06169
Alexander G\'omez Villa
Alexander Gomez, Augusto Salazar and Francisco Vargas
Towards Automatic Wild Animal Monitoring: Identification of Animal Species in Camera-trap Images using Very Deep Convolutional Neural Networks
Submitted to ECCV16
null
null
null
cs.CV
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Non intrusive monitoring of animals in the wild is possible using camera trapping framework, which uses cameras triggered by sensors to take a burst of images of animals in their habitat. However camera trapping framework produces a high volume of data (in the order on thousands or millions of images), which must be analyzed by a human expert. In this work, a method for animal species identification in the wild using very deep convolutional neural networks is presented. Multiple versions of the Snapshot Serengeti dataset were used in order to probe the ability of the method to cope with different challenges that camera-trap images demand. The method reached 88.9% of accuracy in Top-1 and 98.1% in Top-5 in the evaluation set using a residual network topology. Also, the results show that the proposed method outperforms previous approximations and proves that recognition in camera-trap images can be automated.
[ { "version": "v1", "created": "Sun, 20 Mar 2016 00:47:46 GMT" }, { "version": "v2", "created": "Tue, 22 Mar 2016 00:53:37 GMT" } ]
2016-03-23T00:00:00
[ [ "Gomez", "Alexander", "" ], [ "Salazar", "Augusto", "" ], [ "Vargas", "Francisco", "" ] ]
TITLE: Towards Automatic Wild Animal Monitoring: Identification of Animal Species in Camera-trap Images using Very Deep Convolutional Neural Networks ABSTRACT: Non intrusive monitoring of animals in the wild is possible using camera trapping framework, which uses cameras triggered by sensors to take a burst of images of animals in their habitat. However camera trapping framework produces a high volume of data (in the order on thousands or millions of images), which must be analyzed by a human expert. In this work, a method for animal species identification in the wild using very deep convolutional neural networks is presented. Multiple versions of the Snapshot Serengeti dataset were used in order to probe the ability of the method to cope with different challenges that camera-trap images demand. The method reached 88.9% of accuracy in Top-1 and 98.1% in Top-5 in the evaluation set using a residual network topology. Also, the results show that the proposed method outperforms previous approximations and proves that recognition in camera-trap images can be automated.
no_new_dataset
0.937726
1603.06655
Zhen Dong
Zhen Dong, Su Jia, Chi Zhang, Mingtao Pei
Input Aggregated Network for Face Video Representation
null
null
null
null
cs.CV
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Recently, deep neural network has shown promising performance in face image recognition. The inputs of most networks are face images, and there is hardly any work reported in literature on network with face videos as input. To sufficiently discover the useful information contained in face videos, we present a novel network architecture called input aggregated network which is able to learn fixed-length representations for variable-length face videos. To accomplish this goal, an aggregation unit is designed to model a face video with various frames as a point on a Riemannian manifold, and the mapping unit aims at mapping the point into high-dimensional space where face videos belonging to the same subject are close-by and others are distant. These two units together with the frame representation unit build an end-to-end learning system which can learn representations of face videos for the specific tasks. Experiments on two public face video datasets demonstrate the effectiveness of the proposed network.
[ { "version": "v1", "created": "Tue, 22 Mar 2016 01:27:50 GMT" } ]
2016-03-23T00:00:00
[ [ "Dong", "Zhen", "" ], [ "Jia", "Su", "" ], [ "Zhang", "Chi", "" ], [ "Pei", "Mingtao", "" ] ]
TITLE: Input Aggregated Network for Face Video Representation ABSTRACT: Recently, deep neural network has shown promising performance in face image recognition. The inputs of most networks are face images, and there is hardly any work reported in literature on network with face videos as input. To sufficiently discover the useful information contained in face videos, we present a novel network architecture called input aggregated network which is able to learn fixed-length representations for variable-length face videos. To accomplish this goal, an aggregation unit is designed to model a face video with various frames as a point on a Riemannian manifold, and the mapping unit aims at mapping the point into high-dimensional space where face videos belonging to the same subject are close-by and others are distant. These two units together with the frame representation unit build an end-to-end learning system which can learn representations of face videos for the specific tasks. Experiments on two public face video datasets demonstrate the effectiveness of the proposed network.
no_new_dataset
0.949576
1603.06759
Yanwei Pang
Yanwei Pang, Manli Sun, Xiaoheng Jiang, Xuelong Li
Convolution in Convolution for Network in Network
A method of Convolutional Neural Networks
null
null
null
cs.CV
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Network in Netwrok (NiN) is an effective instance and an important extension of Convolutional Neural Network (CNN) consisting of alternating convolutional layers and pooling layers. Instead of using a linear filter for convolution, NiN utilizes shallow MultiLayer Perceptron (MLP), a nonlinear function, to replace the linear filter. Because of the powerfulness of MLP and $ 1\times 1 $ convolutions in spatial domain, NiN has stronger ability of feature representation and hence results in better recognition rate. However, MLP itself consists of fully connected layers which give rise to a large number of parameters. In this paper, we propose to replace dense shallow MLP with sparse shallow MLP. One or more layers of the sparse shallow MLP are sparely connected in the channel dimension or channel-spatial domain. The proposed method is implemented by applying unshared convolution across the channel dimension and applying shared convolution across the spatial dimension in some computational layers. The proposed method is called CiC. Experimental results on the CIFAR10 dataset, augmented CIFAR10 dataset, and CIFAR100 dataset demonstrate the effectiveness of the proposed CiC method.
[ { "version": "v1", "created": "Tue, 22 Mar 2016 12:33:11 GMT" } ]
2016-03-23T00:00:00
[ [ "Pang", "Yanwei", "" ], [ "Sun", "Manli", "" ], [ "Jiang", "Xiaoheng", "" ], [ "Li", "Xuelong", "" ] ]
TITLE: Convolution in Convolution for Network in Network ABSTRACT: Network in Netwrok (NiN) is an effective instance and an important extension of Convolutional Neural Network (CNN) consisting of alternating convolutional layers and pooling layers. Instead of using a linear filter for convolution, NiN utilizes shallow MultiLayer Perceptron (MLP), a nonlinear function, to replace the linear filter. Because of the powerfulness of MLP and $ 1\times 1 $ convolutions in spatial domain, NiN has stronger ability of feature representation and hence results in better recognition rate. However, MLP itself consists of fully connected layers which give rise to a large number of parameters. In this paper, we propose to replace dense shallow MLP with sparse shallow MLP. One or more layers of the sparse shallow MLP are sparely connected in the channel dimension or channel-spatial domain. The proposed method is implemented by applying unshared convolution across the channel dimension and applying shared convolution across the spatial dimension in some computational layers. The proposed method is called CiC. Experimental results on the CIFAR10 dataset, augmented CIFAR10 dataset, and CIFAR100 dataset demonstrate the effectiveness of the proposed CiC method.
no_new_dataset
0.952353
1603.06829
Otkrist Gupta
Otkrist Gupta, Dan Raviv and Ramesh Raskar
Multi-velocity neural networks for gesture recognition in videos
null
null
null
null
cs.CV cs.LG
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We present a new action recognition deep neural network which adaptively learns the best action velocities in addition to the classification. While deep neural networks have reached maturity for image understanding tasks, we are still exploring network topologies and features to handle the richer environment of video clips. Here, we tackle the problem of multiple velocities in action recognition, and provide state-of-the-art results for gesture recognition, on known and new collected datasets. We further provide the training steps for our semi-supervised network, suited to learn from huge unlabeled datasets with only a fraction of labeled examples.
[ { "version": "v1", "created": "Tue, 22 Mar 2016 15:26:26 GMT" } ]
2016-03-23T00:00:00
[ [ "Gupta", "Otkrist", "" ], [ "Raviv", "Dan", "" ], [ "Raskar", "Ramesh", "" ] ]
TITLE: Multi-velocity neural networks for gesture recognition in videos ABSTRACT: We present a new action recognition deep neural network which adaptively learns the best action velocities in addition to the classification. While deep neural networks have reached maturity for image understanding tasks, we are still exploring network topologies and features to handle the richer environment of video clips. Here, we tackle the problem of multiple velocities in action recognition, and provide state-of-the-art results for gesture recognition, on known and new collected datasets. We further provide the training steps for our semi-supervised network, suited to learn from huge unlabeled datasets with only a fraction of labeled examples.
new_dataset
0.943867
1603.06861
Anastasios Kyrillidis
Vatsal Shah, Megasthenis Asteris, Anastasios Kyrillidis, Sujay Sanghavi
Trading-off variance and complexity in stochastic gradient descent
14 pages, 13 figures, first edition on 9th of October 2015
null
null
null
stat.ML cs.IT cs.LG math.IT math.OC
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Stochastic gradient descent is the method of choice for large-scale machine learning problems, by virtue of its light complexity per iteration. However, it lags behind its non-stochastic counterparts with respect to the convergence rate, due to high variance introduced by the stochastic updates. The popular Stochastic Variance-Reduced Gradient (SVRG) method mitigates this shortcoming, introducing a new update rule which requires infrequent passes over the entire input dataset to compute the full-gradient. In this work, we propose CheapSVRG, a stochastic variance-reduction optimization scheme. Our algorithm is similar to SVRG but instead of the full gradient, it uses a surrogate which can be efficiently computed on a small subset of the input data. It achieves a linear convergence rate ---up to some error level, depending on the nature of the optimization problem---and features a trade-off between the computational complexity and the convergence rate. Empirical evaluation shows that CheapSVRG performs at least competitively compared to the state of the art.
[ { "version": "v1", "created": "Tue, 22 Mar 2016 16:34:26 GMT" } ]
2016-03-23T00:00:00
[ [ "Shah", "Vatsal", "" ], [ "Asteris", "Megasthenis", "" ], [ "Kyrillidis", "Anastasios", "" ], [ "Sanghavi", "Sujay", "" ] ]
TITLE: Trading-off variance and complexity in stochastic gradient descent ABSTRACT: Stochastic gradient descent is the method of choice for large-scale machine learning problems, by virtue of its light complexity per iteration. However, it lags behind its non-stochastic counterparts with respect to the convergence rate, due to high variance introduced by the stochastic updates. The popular Stochastic Variance-Reduced Gradient (SVRG) method mitigates this shortcoming, introducing a new update rule which requires infrequent passes over the entire input dataset to compute the full-gradient. In this work, we propose CheapSVRG, a stochastic variance-reduction optimization scheme. Our algorithm is similar to SVRG but instead of the full gradient, it uses a surrogate which can be efficiently computed on a small subset of the input data. It achieves a linear convergence rate ---up to some error level, depending on the nature of the optimization problem---and features a trade-off between the computational complexity and the convergence rate. Empirical evaluation shows that CheapSVRG performs at least competitively compared to the state of the art.
no_new_dataset
0.942612
1402.5874
Mohammad Ghasemi Hamed
Mohammad Ghasemi Hamed, Mathieu Serrurier, Nicolas Durand
Predictive Interval Models for Non-parametric Regression
This paper has been withdrawn by the authors due to multiple errors in the formulations and equations
null
null
null
cs.LG stat.ML
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Having a regression model, we are interested in finding two-sided intervals that are guaranteed to contain at least a desired proportion of the conditional distribution of the response variable given a specific combination of predictors. We name such intervals predictive intervals. This work presents a new method to find two-sided predictive intervals for non-parametric least squares regression without the homoscedasticity assumption. Our predictive intervals are built by using tolerance intervals on prediction errors in the query point's neighborhood. We proposed a predictive interval model test and we also used it as a constraint in our hyper-parameter tuning algorithm. This gives an algorithm that finds the smallest reliable predictive intervals for a given dataset. We also introduce a measure for comparing different interval prediction methods yielding intervals having different size and coverage. These experiments show that our methods are more reliable, effective and precise than other interval prediction methods.
[ { "version": "v1", "created": "Mon, 24 Feb 2014 16:16:17 GMT" }, { "version": "v2", "created": "Mon, 21 Mar 2016 10:56:40 GMT" } ]
2016-03-22T00:00:00
[ [ "Hamed", "Mohammad Ghasemi", "" ], [ "Serrurier", "Mathieu", "" ], [ "Durand", "Nicolas", "" ] ]
TITLE: Predictive Interval Models for Non-parametric Regression ABSTRACT: Having a regression model, we are interested in finding two-sided intervals that are guaranteed to contain at least a desired proportion of the conditional distribution of the response variable given a specific combination of predictors. We name such intervals predictive intervals. This work presents a new method to find two-sided predictive intervals for non-parametric least squares regression without the homoscedasticity assumption. Our predictive intervals are built by using tolerance intervals on prediction errors in the query point's neighborhood. We proposed a predictive interval model test and we also used it as a constraint in our hyper-parameter tuning algorithm. This gives an algorithm that finds the smallest reliable predictive intervals for a given dataset. We also introduce a measure for comparing different interval prediction methods yielding intervals having different size and coverage. These experiments show that our methods are more reliable, effective and precise than other interval prediction methods.
no_new_dataset
0.946051
1503.00164
Yuan Yao
Braxton Osting and Jiechao Xiong and Qianqian Xu and Yuan Yao
Analysis of Crowdsourced Sampling Strategies for HodgeRank with Sparse Random Graphs
null
Applied and Computational Harmonic Analysis, 2016
10.1016/j.acha.2016.03.007
null
stat.ML cs.LG
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Crowdsourcing platforms are now extensively used for conducting subjective pairwise comparison studies. In this setting, a pairwise comparison dataset is typically gathered via random sampling, either \emph{with} or \emph{without} replacement. In this paper, we use tools from random graph theory to analyze these two random sampling methods for the HodgeRank estimator. Using the Fiedler value of the graph as a measurement for estimator stability (informativeness), we provide a new estimate of the Fiedler value for these two random graph models. In the asymptotic limit as the number of vertices tends to infinity, we prove the validity of the estimate. Based on our findings, for a small number of items to be compared, we recommend a two-stage sampling strategy where a greedy sampling method is used initially and random sampling \emph{without} replacement is used in the second stage. When a large number of items is to be compared, we recommend random sampling with replacement as this is computationally inexpensive and trivially parallelizable. Experiments on synthetic and real-world datasets support our analysis.
[ { "version": "v1", "created": "Sat, 28 Feb 2015 18:32:45 GMT" }, { "version": "v2", "created": "Mon, 21 Mar 2016 11:47:10 GMT" } ]
2016-03-22T00:00:00
[ [ "Osting", "Braxton", "" ], [ "Xiong", "Jiechao", "" ], [ "Xu", "Qianqian", "" ], [ "Yao", "Yuan", "" ] ]
TITLE: Analysis of Crowdsourced Sampling Strategies for HodgeRank with Sparse Random Graphs ABSTRACT: Crowdsourcing platforms are now extensively used for conducting subjective pairwise comparison studies. In this setting, a pairwise comparison dataset is typically gathered via random sampling, either \emph{with} or \emph{without} replacement. In this paper, we use tools from random graph theory to analyze these two random sampling methods for the HodgeRank estimator. Using the Fiedler value of the graph as a measurement for estimator stability (informativeness), we provide a new estimate of the Fiedler value for these two random graph models. In the asymptotic limit as the number of vertices tends to infinity, we prove the validity of the estimate. Based on our findings, for a small number of items to be compared, we recommend a two-stage sampling strategy where a greedy sampling method is used initially and random sampling \emph{without} replacement is used in the second stage. When a large number of items is to be compared, we recommend random sampling with replacement as this is computationally inexpensive and trivially parallelizable. Experiments on synthetic and real-world datasets support our analysis.
no_new_dataset
0.954816
1505.05914
Huijuan Xu
Huijuan Xu, Subhashini Venugopalan, Vasili Ramanishka, Marcus Rohrbach, Kate Saenko
A Multi-scale Multiple Instance Video Description Network
ICCV15 workshop on Closing the Loop Between Vision and Language
null
null
null
cs.CV
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Generating natural language descriptions for in-the-wild videos is a challenging task. Most state-of-the-art methods for solving this problem borrow existing deep convolutional neural network (CNN) architectures (AlexNet, GoogLeNet) to extract a visual representation of the input video. However, these deep CNN architectures are designed for single-label centered-positioned object classification. While they generate strong semantic features, they have no inherent structure allowing them to detect multiple objects of different sizes and locations in the frame. Our paper tries to solve this problem by integrating the base CNN into several fully convolutional neural networks (FCNs) to form a multi-scale network that handles multiple receptive field sizes in the original image. FCNs, previously applied to image segmentation, can generate class heat-maps efficiently compared to sliding window mechanisms, and can easily handle multiple scales. To further handle the ambiguity over multiple objects and locations, we incorporate the Multiple Instance Learning mechanism (MIL) to consider objects in different positions and at different scales simultaneously. We integrate our multi-scale multi-instance architecture with a sequence-to-sequence recurrent neural network to generate sentence descriptions based on the visual representation. Ours is the first end-to-end trainable architecture that is capable of multi-scale region processing. Evaluation on a Youtube video dataset shows the advantage of our approach compared to the original single-scale whole frame CNN model. Our flexible and efficient architecture can potentially be extended to support other video processing tasks.
[ { "version": "v1", "created": "Thu, 21 May 2015 21:47:08 GMT" }, { "version": "v2", "created": "Mon, 25 May 2015 16:28:56 GMT" }, { "version": "v3", "created": "Sat, 19 Mar 2016 02:27:58 GMT" } ]
2016-03-22T00:00:00
[ [ "Xu", "Huijuan", "" ], [ "Venugopalan", "Subhashini", "" ], [ "Ramanishka", "Vasili", "" ], [ "Rohrbach", "Marcus", "" ], [ "Saenko", "Kate", "" ] ]
TITLE: A Multi-scale Multiple Instance Video Description Network ABSTRACT: Generating natural language descriptions for in-the-wild videos is a challenging task. Most state-of-the-art methods for solving this problem borrow existing deep convolutional neural network (CNN) architectures (AlexNet, GoogLeNet) to extract a visual representation of the input video. However, these deep CNN architectures are designed for single-label centered-positioned object classification. While they generate strong semantic features, they have no inherent structure allowing them to detect multiple objects of different sizes and locations in the frame. Our paper tries to solve this problem by integrating the base CNN into several fully convolutional neural networks (FCNs) to form a multi-scale network that handles multiple receptive field sizes in the original image. FCNs, previously applied to image segmentation, can generate class heat-maps efficiently compared to sliding window mechanisms, and can easily handle multiple scales. To further handle the ambiguity over multiple objects and locations, we incorporate the Multiple Instance Learning mechanism (MIL) to consider objects in different positions and at different scales simultaneously. We integrate our multi-scale multi-instance architecture with a sequence-to-sequence recurrent neural network to generate sentence descriptions based on the visual representation. Ours is the first end-to-end trainable architecture that is capable of multi-scale region processing. Evaluation on a Youtube video dataset shows the advantage of our approach compared to the original single-scale whole frame CNN model. Our flexible and efficient architecture can potentially be extended to support other video processing tasks.
no_new_dataset
0.94868
1511.05234
Huijuan Xu
Huijuan Xu and Kate Saenko
Ask, Attend and Answer: Exploring Question-Guided Spatial Attention for Visual Question Answering
include test-standard result on VQA full release (V1.0) dataset
null
null
null
cs.CV cs.AI cs.CL cs.NE
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We address the problem of Visual Question Answering (VQA), which requires joint image and language understanding to answer a question about a given photograph. Recent approaches have applied deep image captioning methods based on convolutional-recurrent networks to this problem, but have failed to model spatial inference. To remedy this, we propose a model we call the Spatial Memory Network and apply it to the VQA task. Memory networks are recurrent neural networks with an explicit attention mechanism that selects certain parts of the information stored in memory. Our Spatial Memory Network stores neuron activations from different spatial regions of the image in its memory, and uses the question to choose relevant regions for computing the answer, a process of which constitutes a single "hop" in the network. We propose a novel spatial attention architecture that aligns words with image patches in the first hop, and obtain improved results by adding a second attention hop which considers the whole question to choose visual evidence based on the results of the first hop. To better understand the inference process learned by the network, we design synthetic questions that specifically require spatial inference and visualize the attention weights. We evaluate our model on two published visual question answering datasets, DAQUAR [1] and VQA [2], and obtain improved results compared to a strong deep baseline model (iBOWIMG) which concatenates image and question features to predict the answer [3].
[ { "version": "v1", "created": "Tue, 17 Nov 2015 01:00:04 GMT" }, { "version": "v2", "created": "Sat, 19 Mar 2016 03:06:58 GMT" } ]
2016-03-22T00:00:00
[ [ "Xu", "Huijuan", "" ], [ "Saenko", "Kate", "" ] ]
TITLE: Ask, Attend and Answer: Exploring Question-Guided Spatial Attention for Visual Question Answering ABSTRACT: We address the problem of Visual Question Answering (VQA), which requires joint image and language understanding to answer a question about a given photograph. Recent approaches have applied deep image captioning methods based on convolutional-recurrent networks to this problem, but have failed to model spatial inference. To remedy this, we propose a model we call the Spatial Memory Network and apply it to the VQA task. Memory networks are recurrent neural networks with an explicit attention mechanism that selects certain parts of the information stored in memory. Our Spatial Memory Network stores neuron activations from different spatial regions of the image in its memory, and uses the question to choose relevant regions for computing the answer, a process of which constitutes a single "hop" in the network. We propose a novel spatial attention architecture that aligns words with image patches in the first hop, and obtain improved results by adding a second attention hop which considers the whole question to choose visual evidence based on the results of the first hop. To better understand the inference process learned by the network, we design synthetic questions that specifically require spatial inference and visualize the attention weights. We evaluate our model on two published visual question answering datasets, DAQUAR [1] and VQA [2], and obtain improved results compared to a strong deep baseline model (iBOWIMG) which concatenates image and question features to predict the answer [3].
no_new_dataset
0.952926
1603.06060
Abhijit Guha Roy
Abhijit Guha Roy and Debdoot Sheet
DASA: Domain Adaptation in Stacked Autoencoders using Systematic Dropout
Accepted at Asian Conference on Pattern Recognition 2015
null
null
null
cs.CV cs.LG
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Domain adaptation deals with adapting behaviour of machine learning based systems trained using samples in source domain to their deployment in target domain where the statistics of samples in both domains are dissimilar. The task of directly training or adapting a learner in the target domain is challenged by lack of abundant labeled samples. In this paper we propose a technique for domain adaptation in stacked autoencoder (SAE) based deep neural networks (DNN) performed in two stages: (i) unsupervised weight adaptation using systematic dropouts in mini-batch training, (ii) supervised fine-tuning with limited number of labeled samples in target domain. We experimentally evaluate performance in the problem of retinal vessel segmentation where the SAE-DNN is trained using large number of labeled samples in the source domain (DRIVE dataset) and adapted using less number of labeled samples in target domain (STARE dataset). The performance of SAE-DNN measured using $logloss$ in source domain is $0.19$, without and with adaptation are $0.40$ and $0.18$, and $0.39$ when trained exclusively with limited samples in target domain. The area under ROC curve is observed respectively as $0.90$, $0.86$, $0.92$ and $0.87$. The high efficiency of vessel segmentation with DASA strongly substantiates our claim.
[ { "version": "v1", "created": "Sat, 19 Mar 2016 07:27:56 GMT" } ]
2016-03-22T00:00:00
[ [ "Roy", "Abhijit Guha", "" ], [ "Sheet", "Debdoot", "" ] ]
TITLE: DASA: Domain Adaptation in Stacked Autoencoders using Systematic Dropout ABSTRACT: Domain adaptation deals with adapting behaviour of machine learning based systems trained using samples in source domain to their deployment in target domain where the statistics of samples in both domains are dissimilar. The task of directly training or adapting a learner in the target domain is challenged by lack of abundant labeled samples. In this paper we propose a technique for domain adaptation in stacked autoencoder (SAE) based deep neural networks (DNN) performed in two stages: (i) unsupervised weight adaptation using systematic dropouts in mini-batch training, (ii) supervised fine-tuning with limited number of labeled samples in target domain. We experimentally evaluate performance in the problem of retinal vessel segmentation where the SAE-DNN is trained using large number of labeled samples in the source domain (DRIVE dataset) and adapted using less number of labeled samples in target domain (STARE dataset). The performance of SAE-DNN measured using $logloss$ in source domain is $0.19$, without and with adaptation are $0.40$ and $0.18$, and $0.39$ when trained exclusively with limited samples in target domain. The area under ROC curve is observed respectively as $0.90$, $0.86$, $0.92$ and $0.87$. The high efficiency of vessel segmentation with DASA strongly substantiates our claim.
no_new_dataset
0.948155
1603.06129
Rishabh Singh
Sahil Bhatia and Rishabh Singh
Automated Correction for Syntax Errors in Programming Assignments using Recurrent Neural Networks
null
null
null
null
cs.PL cs.AI cs.LG cs.SE
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We present a method for automatically generating repair feedback for syntax errors for introductory programming problems. Syntax errors constitute one of the largest classes of errors (34%) in our dataset of student submissions obtained from a MOOC course on edX. The previous techniques for generating automated feed- back on programming assignments have focused on functional correctness and style considerations of student programs. These techniques analyze the program AST of the program and then perform some dynamic and symbolic analyses to compute repair feedback. Unfortunately, it is not possible to generate ASTs for student pro- grams with syntax errors and therefore the previous feedback techniques are not applicable in repairing syntax errors. We present a technique for providing feedback on syntax errors that uses Recurrent neural networks (RNNs) to model syntactically valid token sequences. Our approach is inspired from the recent work on learning language models from Big Code (large code corpus). For a given programming assignment, we first learn an RNN to model all valid token sequences using the set of syntactically correct student submissions. Then, for a student submission with syntax errors, we query the learnt RNN model with the prefix to- ken sequence to predict token sequences that can fix the error by either replacing or inserting the predicted token sequence at the error location. We evaluate our technique on over 14, 000 student submissions with syntax errors. Our technique can completely re- pair 31.69% (4501/14203) of submissions with syntax errors and in addition partially correct 6.39% (908/14203) of the submissions.
[ { "version": "v1", "created": "Sat, 19 Mar 2016 18:43:28 GMT" } ]
2016-03-22T00:00:00
[ [ "Bhatia", "Sahil", "" ], [ "Singh", "Rishabh", "" ] ]
TITLE: Automated Correction for Syntax Errors in Programming Assignments using Recurrent Neural Networks ABSTRACT: We present a method for automatically generating repair feedback for syntax errors for introductory programming problems. Syntax errors constitute one of the largest classes of errors (34%) in our dataset of student submissions obtained from a MOOC course on edX. The previous techniques for generating automated feed- back on programming assignments have focused on functional correctness and style considerations of student programs. These techniques analyze the program AST of the program and then perform some dynamic and symbolic analyses to compute repair feedback. Unfortunately, it is not possible to generate ASTs for student pro- grams with syntax errors and therefore the previous feedback techniques are not applicable in repairing syntax errors. We present a technique for providing feedback on syntax errors that uses Recurrent neural networks (RNNs) to model syntactically valid token sequences. Our approach is inspired from the recent work on learning language models from Big Code (large code corpus). For a given programming assignment, we first learn an RNN to model all valid token sequences using the set of syntactically correct student submissions. Then, for a student submission with syntax errors, we query the learnt RNN model with the prefix to- ken sequence to predict token sequences that can fix the error by either replacing or inserting the predicted token sequence at the error location. We evaluate our technique on over 14, 000 student submissions with syntax errors. Our technique can completely re- pair 31.69% (4501/14203) of submissions with syntax errors and in addition partially correct 6.39% (908/14203) of the submissions.
no_new_dataset
0.762601
1603.06180
Ronghang Hu
Ronghang Hu, Marcus Rohrbach, Trevor Darrell
Segmentation from Natural Language Expressions
null
null
null
null
cs.CV
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
In this paper we approach the novel problem of segmenting an image based on a natural language expression. This is different from traditional semantic segmentation over a predefined set of semantic classes, as e.g., the phrase "two men sitting on the right bench" requires segmenting only the two people on the right bench and no one standing or sitting on another bench. Previous approaches suitable for this task were limited to a fixed set of categories and/or rectangular regions. To produce pixelwise segmentation for the language expression, we propose an end-to-end trainable recurrent and convolutional network model that jointly learns to process visual and linguistic information. In our model, a recurrent LSTM network is used to encode the referential expression into a vector representation, and a fully convolutional network is used to a extract a spatial feature map from the image and output a spatial response map for the target object. We demonstrate on a benchmark dataset that our model can produce quality segmentation output from the natural language expression, and outperforms baseline methods by a large margin.
[ { "version": "v1", "created": "Sun, 20 Mar 2016 04:10:53 GMT" } ]
2016-03-22T00:00:00
[ [ "Hu", "Ronghang", "" ], [ "Rohrbach", "Marcus", "" ], [ "Darrell", "Trevor", "" ] ]
TITLE: Segmentation from Natural Language Expressions ABSTRACT: In this paper we approach the novel problem of segmenting an image based on a natural language expression. This is different from traditional semantic segmentation over a predefined set of semantic classes, as e.g., the phrase "two men sitting on the right bench" requires segmenting only the two people on the right bench and no one standing or sitting on another bench. Previous approaches suitable for this task were limited to a fixed set of categories and/or rectangular regions. To produce pixelwise segmentation for the language expression, we propose an end-to-end trainable recurrent and convolutional network model that jointly learns to process visual and linguistic information. In our model, a recurrent LSTM network is used to encode the referential expression into a vector representation, and a fully convolutional network is used to a extract a spatial feature map from the image and output a spatial response map for the target object. We demonstrate on a benchmark dataset that our model can produce quality segmentation output from the natural language expression, and outperforms baseline methods by a large margin.
no_new_dataset
0.947866
1603.06289
Muhammad Ikram
Muhammad Ikram, Hassan Jameel Asghar, Mohamed Ali Kaafar, Balachander Krishnamurthy, Anirban Mahanti
Towards Seamless Tracking-Free Web: Improved Detection of Trackers via One-class Learning
null
null
null
null
cs.CR
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Numerous tools have been developed to aggressively block the execution of popular JavaScript programs (JS) in Web browsers. Such blocking also affects functionality of webpages and impairs user experience. As a consequence, many privacy preserving tools (PP-Tools) that have been developed to limit online tracking, often executed via JS, may suffer from poor performance and limited uptake. A mechanism that can isolate JS necessary for proper functioning of the website from tracking JS would thus be useful. Through the use of a manually labelled dataset composed of 2,612 JS, we show how current PP-Tools are ineffective in finding the right balance between blocking tracking JS and allowing functional JS. To the best of our knowledge, this is the first study to assess the performance of current web PP-Tools. To improve this balance, we examine the two classes of JS and hypothesize that tracking JS share structural similarities that can be used to differentiate them from functional JS. The rationale of our approach is that web developers often borrow and customize existing pieces of code in order to embed tracking (resp. functional) JS into their webpages. We then propose one-class machine learning classifiers using syntactic and semantic features extracted from JS. When trained only on samples of tracking JS, our classifiers achieve an accuracy of 99%, where the best of the PP-Tools achieved an accuracy of 78%. We further test our classifiers and several popular PP-Tools on a corpus of 4K websites with 135K JS. The output of our best classifier on this data is between 20 to 64% different from the PP-Tools. We manually analyse a sample of the JS for which our classifier is in disagreement with all other PP-Tools, and show that our approach is not only able to enhance user web experience by correctly classifying more functional JS, but also discovers previously unknown tracking services.
[ { "version": "v1", "created": "Sun, 20 Mar 2016 23:33:55 GMT" } ]
2016-03-22T00:00:00
[ [ "Ikram", "Muhammad", "" ], [ "Asghar", "Hassan Jameel", "" ], [ "Kaafar", "Mohamed Ali", "" ], [ "Krishnamurthy", "Balachander", "" ], [ "Mahanti", "Anirban", "" ] ]
TITLE: Towards Seamless Tracking-Free Web: Improved Detection of Trackers via One-class Learning ABSTRACT: Numerous tools have been developed to aggressively block the execution of popular JavaScript programs (JS) in Web browsers. Such blocking also affects functionality of webpages and impairs user experience. As a consequence, many privacy preserving tools (PP-Tools) that have been developed to limit online tracking, often executed via JS, may suffer from poor performance and limited uptake. A mechanism that can isolate JS necessary for proper functioning of the website from tracking JS would thus be useful. Through the use of a manually labelled dataset composed of 2,612 JS, we show how current PP-Tools are ineffective in finding the right balance between blocking tracking JS and allowing functional JS. To the best of our knowledge, this is the first study to assess the performance of current web PP-Tools. To improve this balance, we examine the two classes of JS and hypothesize that tracking JS share structural similarities that can be used to differentiate them from functional JS. The rationale of our approach is that web developers often borrow and customize existing pieces of code in order to embed tracking (resp. functional) JS into their webpages. We then propose one-class machine learning classifiers using syntactic and semantic features extracted from JS. When trained only on samples of tracking JS, our classifiers achieve an accuracy of 99%, where the best of the PP-Tools achieved an accuracy of 78%. We further test our classifiers and several popular PP-Tools on a corpus of 4K websites with 135K JS. The output of our best classifier on this data is between 20 to 64% different from the PP-Tools. We manually analyse a sample of the JS for which our classifier is in disagreement with all other PP-Tools, and show that our approach is not only able to enhance user web experience by correctly classifying more functional JS, but also discovers previously unknown tracking services.
no_new_dataset
0.929824
1603.06371
Floriana Gargiulo
Floriana Gargiulo, Auguste Caen, Renaud Lambiotte and Timoteo Carletti
The classical origin of modern mathematics
null
null
null
null
math.HO cs.CY physics.data-an physics.soc-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The aim of this paper is to study the historical evolution of mathematical thinking and its spatial spreading. To do so, we have collected and integrated data from different online academic datasets. In its final stage, the database includes a large number (N~200K) of advisor-student relationships, with affiliations and keywords on their research topic, over several centuries, from the 14th century until today. We focus on two different topics, the evolving importance of countries and of the research disciplines over time. Moreover we study the database at three levels, its global statistics, the mesoscale networks connecting countries and disciplines, and the genealogical level.
[ { "version": "v1", "created": "Mon, 21 Mar 2016 09:53:49 GMT" } ]
2016-03-22T00:00:00
[ [ "Gargiulo", "Floriana", "" ], [ "Caen", "Auguste", "" ], [ "Lambiotte", "Renaud", "" ], [ "Carletti", "Timoteo", "" ] ]
TITLE: The classical origin of modern mathematics ABSTRACT: The aim of this paper is to study the historical evolution of mathematical thinking and its spatial spreading. To do so, we have collected and integrated data from different online academic datasets. In its final stage, the database includes a large number (N~200K) of advisor-student relationships, with affiliations and keywords on their research topic, over several centuries, from the 14th century until today. We focus on two different topics, the evolving importance of countries and of the research disciplines over time. Moreover we study the database at three levels, its global statistics, the mesoscale networks connecting countries and disciplines, and the genealogical level.
no_new_dataset
0.93511
1603.06398
Liqian Ma
Liqian Ma, Jue Wang, Eli Shechtman, Kalyan Sunkavalli, Shimin Hu
Appearance Harmonization for Single Image Shadow Removal
null
null
null
null
cs.CV
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Shadows often create unwanted artifacts in photographs, and removing them can be very challenging. Previous shadow removal methods often produce de-shadowed regions that are visually inconsistent with the rest of the image. In this work we propose a fully automatic shadow region harmonization approach that improves the appearance compatibility of the de-shadowed region as typically produced by previous methods. It is based on a shadow-guided patch-based image synthesis approach that reconstructs the shadow region using patches sampled from non-shadowed regions. The result is then refined based on the reconstruction confidence to handle unique image patterns. Many shadow removal results and comparisons are show the effectiveness of our improvement. Quantitative evaluation on a benchmark dataset suggests that our automatic shadow harmonization approach effectively improves upon the state-of-the-art.
[ { "version": "v1", "created": "Mon, 21 Mar 2016 12:01:36 GMT" } ]
2016-03-22T00:00:00
[ [ "Ma", "Liqian", "" ], [ "Wang", "Jue", "" ], [ "Shechtman", "Eli", "" ], [ "Sunkavalli", "Kalyan", "" ], [ "Hu", "Shimin", "" ] ]
TITLE: Appearance Harmonization for Single Image Shadow Removal ABSTRACT: Shadows often create unwanted artifacts in photographs, and removing them can be very challenging. Previous shadow removal methods often produce de-shadowed regions that are visually inconsistent with the rest of the image. In this work we propose a fully automatic shadow region harmonization approach that improves the appearance compatibility of the de-shadowed region as typically produced by previous methods. It is based on a shadow-guided patch-based image synthesis approach that reconstructs the shadow region using patches sampled from non-shadowed regions. The result is then refined based on the reconstruction confidence to handle unique image patterns. Many shadow removal results and comparisons are show the effectiveness of our improvement. Quantitative evaluation on a benchmark dataset suggests that our automatic shadow harmonization approach effectively improves upon the state-of-the-art.
no_new_dataset
0.955527
1603.06531
Otkrist Gupta
Otkrist Gupta, Dan Raviv, Ramesh Raskar
Deep video gesture recognition using illumination invariants
null
null
null
null
cs.CV cs.LG
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
In this paper we present architectures based on deep neural nets for gesture recognition in videos, which are invariant to local scaling. We amalgamate autoencoder and predictor architectures using an adaptive weighting scheme coping with a reduced size labeled dataset, while enriching our models from enormous unlabeled sets. We further improve robustness to lighting conditions by introducing a new adaptive filer based on temporal local scale normalization. We provide superior results over known methods, including recent reported approaches based on neural nets.
[ { "version": "v1", "created": "Mon, 21 Mar 2016 18:33:29 GMT" } ]
2016-03-22T00:00:00
[ [ "Gupta", "Otkrist", "" ], [ "Raviv", "Dan", "" ], [ "Raskar", "Ramesh", "" ] ]
TITLE: Deep video gesture recognition using illumination invariants ABSTRACT: In this paper we present architectures based on deep neural nets for gesture recognition in videos, which are invariant to local scaling. We amalgamate autoencoder and predictor architectures using an adaptive weighting scheme coping with a reduced size labeled dataset, while enriching our models from enormous unlabeled sets. We further improve robustness to lighting conditions by introducing a new adaptive filer based on temporal local scale normalization. We provide superior results over known methods, including recent reported approaches based on neural nets.
no_new_dataset
0.944995
1603.06541
Ping Li
Ping Li
A Comparison Study of Nonlinear Kernels
null
null
null
null
stat.ML cs.LG
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
In this paper, we compare 5 different nonlinear kernels: min-max, RBF, fRBF (folded RBF), acos, and acos-$\chi^2$, on a wide range of publicly available datasets. The proposed fRBF kernel performs very similarly to the RBF kernel. Both RBF and fRBF kernels require an important tuning parameter ($\gamma$). Interestingly, for a significant portion of the datasets, the min-max kernel outperforms the best-tuned RBF/fRBF kernels. The acos kernel and acos-$\chi^2$ kernel also perform well in general and in some datasets achieve the best accuracies. One crucial issue with the use of nonlinear kernels is the excessive computational and memory cost. These days, one increasingly popular strategy is to linearize the kernels through various randomization algorithms. In our study, the randomization method for the min-max kernel demonstrates excellent performance compared to the randomization methods for other types of nonlinear kernels, measured in terms of the number of nonzero terms in the transformed dataset. Our study provides evidence for supporting the use of the min-max kernel and the corresponding randomized linearization method (i.e., the so-called "0-bit CWS"). Furthermore, the results motivate at least two directions for future research: (i) To develop new (and linearizable) nonlinear kernels for better accuracies; and (ii) To develop better linearization algorithms for improving the current linearization methods for the RBF kernel, the acos kernel, and the acos-$\chi^2$ kernel. One attempt is to combine the min-max kernel with the acos kernel or the acos-$\chi^2$ kernel. The advantages of these two new and tuning-free nonlinear kernels are demonstrated vias our extensive experiments.
[ { "version": "v1", "created": "Mon, 21 Mar 2016 19:11:50 GMT" } ]
2016-03-22T00:00:00
[ [ "Li", "Ping", "" ] ]
TITLE: A Comparison Study of Nonlinear Kernels ABSTRACT: In this paper, we compare 5 different nonlinear kernels: min-max, RBF, fRBF (folded RBF), acos, and acos-$\chi^2$, on a wide range of publicly available datasets. The proposed fRBF kernel performs very similarly to the RBF kernel. Both RBF and fRBF kernels require an important tuning parameter ($\gamma$). Interestingly, for a significant portion of the datasets, the min-max kernel outperforms the best-tuned RBF/fRBF kernels. The acos kernel and acos-$\chi^2$ kernel also perform well in general and in some datasets achieve the best accuracies. One crucial issue with the use of nonlinear kernels is the excessive computational and memory cost. These days, one increasingly popular strategy is to linearize the kernels through various randomization algorithms. In our study, the randomization method for the min-max kernel demonstrates excellent performance compared to the randomization methods for other types of nonlinear kernels, measured in terms of the number of nonzero terms in the transformed dataset. Our study provides evidence for supporting the use of the min-max kernel and the corresponding randomized linearization method (i.e., the so-called "0-bit CWS"). Furthermore, the results motivate at least two directions for future research: (i) To develop new (and linearizable) nonlinear kernels for better accuracies; and (ii) To develop better linearization algorithms for improving the current linearization methods for the RBF kernel, the acos kernel, and the acos-$\chi^2$ kernel. One attempt is to combine the min-max kernel with the acos kernel or the acos-$\chi^2$ kernel. The advantages of these two new and tuning-free nonlinear kernels are demonstrated vias our extensive experiments.
no_new_dataset
0.950319
1603.06554
Mohamed Amer
Timothy J. Shields, Mohamed R. Amer, Max Ehrlich, Amir Tamrakar
Action-Affect Classification and Morphing using Multi-Task Representation Learning
null
null
null
null
cs.CV cs.AI cs.HC cs.LG
http://creativecommons.org/licenses/by-sa/4.0/
Most recent work focused on affect from facial expressions, and not as much on body. This work focuses on body affect analysis. Affect does not occur in isolation. Humans usually couple affect with an action in natural interactions; for example, a person could be talking and smiling. Recognizing body affect in sequences requires efficient algorithms to capture both the micro movements that differentiate between happy and sad and the macro variations between different actions. We depart from traditional approaches for time-series data analytics by proposing a multi-task learning model that learns a shared representation that is well-suited for action-affect classification as well as generation. For this paper we choose Conditional Restricted Boltzmann Machines to be our building block. We propose a new model that enhances the CRBM model with a factored multi-task component to become Multi-Task Conditional Restricted Boltzmann Machines (MTCRBMs). We evaluate our approach on two publicly available datasets, the Body Affect dataset and the Tower Game dataset, and show superior classification performance improvement over the state-of-the-art, as well as the generative abilities of our model.
[ { "version": "v1", "created": "Mon, 21 Mar 2016 19:38:07 GMT" } ]
2016-03-22T00:00:00
[ [ "Shields", "Timothy J.", "" ], [ "Amer", "Mohamed R.", "" ], [ "Ehrlich", "Max", "" ], [ "Tamrakar", "Amir", "" ] ]
TITLE: Action-Affect Classification and Morphing using Multi-Task Representation Learning ABSTRACT: Most recent work focused on affect from facial expressions, and not as much on body. This work focuses on body affect analysis. Affect does not occur in isolation. Humans usually couple affect with an action in natural interactions; for example, a person could be talking and smiling. Recognizing body affect in sequences requires efficient algorithms to capture both the micro movements that differentiate between happy and sad and the macro variations between different actions. We depart from traditional approaches for time-series data analytics by proposing a multi-task learning model that learns a shared representation that is well-suited for action-affect classification as well as generation. For this paper we choose Conditional Restricted Boltzmann Machines to be our building block. We propose a new model that enhances the CRBM model with a factored multi-task component to become Multi-Task Conditional Restricted Boltzmann Machines (MTCRBMs). We evaluate our approach on two publicly available datasets, the Body Affect dataset and the Tower Game dataset, and show superior classification performance improvement over the state-of-the-art, as well as the generative abilities of our model.
no_new_dataset
0.944074
1508.03865
Yannick Meier
Yannick Meier, Jie Xu, Onur Atan and Mihaela van der Schaar
Predicting Grades
15 pages, 15 figures
IEEE Transactions on Signal Processing, vol. 64, no. 4, pp. 959-972, Feb.15, 2016
10.1109/TSP.2015.2496278
null
cs.LG
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
To increase efficacy in traditional classroom courses as well as in Massive Open Online Courses (MOOCs), automated systems supporting the instructor are needed. One important problem is to automatically detect students that are going to do poorly in a course early enough to be able to take remedial actions. Existing grade prediction systems focus on maximizing the accuracy of the prediction while overseeing the importance of issuing timely and personalized predictions. This paper proposes an algorithm that predicts the final grade of each student in a class. It issues a prediction for each student individually, when the expected accuracy of the prediction is sufficient. The algorithm learns online what is the optimal prediction and time to issue a prediction based on past history of students' performance in a course. We derive a confidence estimate for the prediction accuracy and demonstrate the performance of our algorithm on a dataset obtained based on the performance of approximately 700 UCLA undergraduate students who have taken an introductory digital signal processing over the past 7 years. We demonstrate that for 85% of the students we can predict with 76% accuracy whether they are going do well or poorly in the class after the 4th course week. Using data obtained from a pilot course, our methodology suggests that it is effective to perform early in-class assessments such as quizzes, which result in timely performance prediction for each student, thereby enabling timely interventions by the instructor (at the student or class level) when necessary.
[ { "version": "v1", "created": "Sun, 16 Aug 2015 20:53:09 GMT" }, { "version": "v2", "created": "Fri, 18 Mar 2016 15:52:33 GMT" } ]
2016-03-21T00:00:00
[ [ "Meier", "Yannick", "" ], [ "Xu", "Jie", "" ], [ "Atan", "Onur", "" ], [ "van der Schaar", "Mihaela", "" ] ]
TITLE: Predicting Grades ABSTRACT: To increase efficacy in traditional classroom courses as well as in Massive Open Online Courses (MOOCs), automated systems supporting the instructor are needed. One important problem is to automatically detect students that are going to do poorly in a course early enough to be able to take remedial actions. Existing grade prediction systems focus on maximizing the accuracy of the prediction while overseeing the importance of issuing timely and personalized predictions. This paper proposes an algorithm that predicts the final grade of each student in a class. It issues a prediction for each student individually, when the expected accuracy of the prediction is sufficient. The algorithm learns online what is the optimal prediction and time to issue a prediction based on past history of students' performance in a course. We derive a confidence estimate for the prediction accuracy and demonstrate the performance of our algorithm on a dataset obtained based on the performance of approximately 700 UCLA undergraduate students who have taken an introductory digital signal processing over the past 7 years. We demonstrate that for 85% of the students we can predict with 76% accuracy whether they are going do well or poorly in the class after the 4th course week. Using data obtained from a pilot course, our methodology suggests that it is effective to perform early in-class assessments such as quizzes, which result in timely performance prediction for each student, thereby enabling timely interventions by the instructor (at the student or class level) when necessary.
no_new_dataset
0.941277
1601.06062
Matthias Hoffmann
Matthias Hoffmann, Christopher Kowalewski, Andreas Maier, Klaus Kurzidim, Norbert Strobel, Joachim Hornegger
3-D/2-D Registration of Cardiac Structures by 3-D Contrast Agent Distribution Estimation
null
null
10.1155/2016/7690391
null
cs.CV
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
For augmented fluoroscopy during cardiac catheter ablation procedures, a preoperatively acquired 3-D model of the left atrium of the patient can be registered to X-ray images. Therefore the 3D-model is matched with the contrast agent based appearance of the left atrium. Commonly, only small amounts of contrast agent (CA) are used to locate the left atrium. This is why we focus on robust registration methods that work also if the structure of interest is only partially contrasted. In particular, we propose two similarity measures for CA-based registration: The first similarity measure, explicit apparent edges, focuses on edges of the patient anatomy made visible by contrast agent and can be computed quickly on the GPU. The second novel similarity measure computes a contrast agent distribution estimate (CADE) inside the 3-D model and rates its consistency with the CA seen in biplane fluoroscopic images. As the CADE computation involves a reconstruction of CA in 3-D using the CA within the fluoroscopic images, it is slower. Using a combination of both methods, our evaluation on 11 well-contrasted clinical datasets yielded an error of 7.9+/-6.3 mm over all frames. For 10 datasets with little CA, we obtained an error of 8.8+/-6.7 mm. Our new methods outperform a registration based on the projected shadow significantly (p<0.05).
[ { "version": "v1", "created": "Fri, 22 Jan 2016 16:23:25 GMT" } ]
2016-03-21T00:00:00
[ [ "Hoffmann", "Matthias", "" ], [ "Kowalewski", "Christopher", "" ], [ "Maier", "Andreas", "" ], [ "Kurzidim", "Klaus", "" ], [ "Strobel", "Norbert", "" ], [ "Hornegger", "Joachim", "" ] ]
TITLE: 3-D/2-D Registration of Cardiac Structures by 3-D Contrast Agent Distribution Estimation ABSTRACT: For augmented fluoroscopy during cardiac catheter ablation procedures, a preoperatively acquired 3-D model of the left atrium of the patient can be registered to X-ray images. Therefore the 3D-model is matched with the contrast agent based appearance of the left atrium. Commonly, only small amounts of contrast agent (CA) are used to locate the left atrium. This is why we focus on robust registration methods that work also if the structure of interest is only partially contrasted. In particular, we propose two similarity measures for CA-based registration: The first similarity measure, explicit apparent edges, focuses on edges of the patient anatomy made visible by contrast agent and can be computed quickly on the GPU. The second novel similarity measure computes a contrast agent distribution estimate (CADE) inside the 3-D model and rates its consistency with the CA seen in biplane fluoroscopic images. As the CADE computation involves a reconstruction of CA in 3-D using the CA within the fluoroscopic images, it is slower. Using a combination of both methods, our evaluation on 11 well-contrasted clinical datasets yielded an error of 7.9+/-6.3 mm over all frames. For 10 datasets with little CA, we obtained an error of 8.8+/-6.7 mm. Our new methods outperform a registration based on the projected shadow significantly (p<0.05).
no_new_dataset
0.956431
1603.05772
Matthias Nie{\ss}ner
Julien Valentin and Angela Dai and Matthias Nie{\ss}ner and Pushmeet Kohli and Philip Torr and Shahram Izadi and Cem Keskin
Learning to Navigate the Energy Landscape
null
null
null
null
cs.CV
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
In this paper, we present a novel and efficient architecture for addressing computer vision problems that use `Analysis by Synthesis'. Analysis by synthesis involves the minimization of the reconstruction error which is typically a non-convex function of the latent target variables. State-of-the-art methods adopt a hybrid scheme where discriminatively trained predictors like Random Forests or Convolutional Neural Networks are used to initialize local search algorithms. While these methods have been shown to produce promising results, they often get stuck in local optima. Our method goes beyond the conventional hybrid architecture by not only proposing multiple accurate initial solutions but by also defining a navigational structure over the solution space that can be used for extremely efficient gradient-free local search. We demonstrate the efficacy of our approach on the challenging problem of RGB Camera Relocalization. To make the RGB camera relocalization problem particularly challenging, we introduce a new dataset of 3D environments which are significantly larger than those found in other publicly-available datasets. Our experiments reveal that the proposed method is able to achieve state-of-the-art camera relocalization results. We also demonstrate the generalizability of our approach on Hand Pose Estimation and Image Retrieval tasks.
[ { "version": "v1", "created": "Fri, 18 Mar 2016 05:45:39 GMT" } ]
2016-03-21T00:00:00
[ [ "Valentin", "Julien", "" ], [ "Dai", "Angela", "" ], [ "Nießner", "Matthias", "" ], [ "Kohli", "Pushmeet", "" ], [ "Torr", "Philip", "" ], [ "Izadi", "Shahram", "" ], [ "Keskin", "Cem", "" ] ]
TITLE: Learning to Navigate the Energy Landscape ABSTRACT: In this paper, we present a novel and efficient architecture for addressing computer vision problems that use `Analysis by Synthesis'. Analysis by synthesis involves the minimization of the reconstruction error which is typically a non-convex function of the latent target variables. State-of-the-art methods adopt a hybrid scheme where discriminatively trained predictors like Random Forests or Convolutional Neural Networks are used to initialize local search algorithms. While these methods have been shown to produce promising results, they often get stuck in local optima. Our method goes beyond the conventional hybrid architecture by not only proposing multiple accurate initial solutions but by also defining a navigational structure over the solution space that can be used for extremely efficient gradient-free local search. We demonstrate the efficacy of our approach on the challenging problem of RGB Camera Relocalization. To make the RGB camera relocalization problem particularly challenging, we introduce a new dataset of 3D environments which are significantly larger than those found in other publicly-available datasets. Our experiments reveal that the proposed method is able to achieve state-of-the-art camera relocalization results. We also demonstrate the generalizability of our approach on Hand Pose Estimation and Image Retrieval tasks.
new_dataset
0.955817
1603.05782
Xiangyu Wang
Xiangyu Wang and Alex Yong-Sang Chia
Unsupervised Cross-Media Hashing with Structure Preservation
null
null
null
null
cs.CV cs.IR
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Recent years have seen the exponential growth of heterogeneous multimedia data. The need for effective and accurate data retrieval from heterogeneous data sources has attracted much research interest in cross-media retrieval. Here, given a query of any media type, cross-media retrieval seeks to find relevant results of different media types from heterogeneous data sources. To facilitate large-scale cross-media retrieval, we propose a novel unsupervised cross-media hashing method. Our method incorporates local affinity and distance repulsion constraints into a matrix factorization framework. Correspondingly, the proposed method learns hash functions that generates unified hash codes from different media types, while ensuring intrinsic geometric structure of the data distribution is preserved. These hash codes empower the similarity between data of different media types to be evaluated directly. Experimental results on two large-scale multimedia datasets demonstrate the effectiveness of the proposed method, where we outperform the state-of-the-art methods.
[ { "version": "v1", "created": "Fri, 18 Mar 2016 07:10:35 GMT" } ]
2016-03-21T00:00:00
[ [ "Wang", "Xiangyu", "" ], [ "Chia", "Alex Yong-Sang", "" ] ]
TITLE: Unsupervised Cross-Media Hashing with Structure Preservation ABSTRACT: Recent years have seen the exponential growth of heterogeneous multimedia data. The need for effective and accurate data retrieval from heterogeneous data sources has attracted much research interest in cross-media retrieval. Here, given a query of any media type, cross-media retrieval seeks to find relevant results of different media types from heterogeneous data sources. To facilitate large-scale cross-media retrieval, we propose a novel unsupervised cross-media hashing method. Our method incorporates local affinity and distance repulsion constraints into a matrix factorization framework. Correspondingly, the proposed method learns hash functions that generates unified hash codes from different media types, while ensuring intrinsic geometric structure of the data distribution is preserved. These hash codes empower the similarity between data of different media types to be evaluated directly. Experimental results on two large-scale multimedia datasets demonstrate the effectiveness of the proposed method, where we outperform the state-of-the-art methods.
no_new_dataset
0.946498
1603.05824
Lars Hertel
Lars Hertel, Huy Phan, Alfred Mertins
Comparing Time and Frequency Domain for Audio Event Recognition Using Deep Learning
5 pages, accepted version for publication in Proceedings of the IEEE International Joint Conference on Neural Networks (IJCNN), July 2016, Vancouver, Canada
null
null
null
cs.NE cs.LG cs.SD
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Recognizing acoustic events is an intricate problem for a machine and an emerging field of research. Deep neural networks achieve convincing results and are currently the state-of-the-art approach for many tasks. One advantage is their implicit feature learning, opposite to an explicit feature extraction of the input signal. In this work, we analyzed whether more discriminative features can be learned from either the time-domain or the frequency-domain representation of the audio signal. For this purpose, we trained multiple deep networks with different architectures on the Freiburg-106 and ESC-10 datasets. Our results show that feature learning from the frequency domain is superior to the time domain. Moreover, additionally using convolution and pooling layers, to explore local structures of the audio signal, significantly improves the recognition performance and achieves state-of-the-art results.
[ { "version": "v1", "created": "Fri, 18 Mar 2016 10:38:23 GMT" } ]
2016-03-21T00:00:00
[ [ "Hertel", "Lars", "" ], [ "Phan", "Huy", "" ], [ "Mertins", "Alfred", "" ] ]
TITLE: Comparing Time and Frequency Domain for Audio Event Recognition Using Deep Learning ABSTRACT: Recognizing acoustic events is an intricate problem for a machine and an emerging field of research. Deep neural networks achieve convincing results and are currently the state-of-the-art approach for many tasks. One advantage is their implicit feature learning, opposite to an explicit feature extraction of the input signal. In this work, we analyzed whether more discriminative features can be learned from either the time-domain or the frequency-domain representation of the audio signal. For this purpose, we trained multiple deep networks with different architectures on the Freiburg-106 and ESC-10 datasets. Our results show that feature learning from the frequency domain is superior to the time domain. Moreover, additionally using convolution and pooling layers, to explore local structures of the audio signal, significantly improves the recognition performance and achieves state-of-the-art results.
no_new_dataset
0.950595
1603.05850
Joey Tianyi Zhou Dr
Joey Tianyi Zhou, Ivor W. Tsang, Shen-Shyang Ho and Klaus-Robert Muller
N-ary Error Correcting Coding Scheme
Under submission to IEEE Transaction on Information Theory
null
null
null
cs.LG
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The coding matrix design plays a fundamental role in the prediction performance of the error correcting output codes (ECOC)-based multi-class task. {In many-class classification problems, e.g., fine-grained categorization, it is difficult to distinguish subtle between-class differences under existing coding schemes due to a limited choices of coding values.} In this paper, we investigate whether one can relax existing binary and ternary code design to $N$-ary code design to achieve better classification performance. {In particular, we present a novel $N$-ary coding scheme that decomposes the original multi-class problem into simpler multi-class subproblems, which is similar to applying a divide-and-conquer method.} The two main advantages of such a coding scheme are as follows: (i) the ability to construct more discriminative codes and (ii) the flexibility for the user to select the best $N$ for ECOC-based classification. We show empirically that the optimal $N$ (based on classification performance) lies in $[3, 10]$ with some trade-off in computational cost. Moreover, we provide theoretical insights on the dependency of the generalization error bound of an $N$-ary ECOC on the average base classifier generalization error and the minimum distance between any two codes constructed. Extensive experimental results on benchmark multi-class datasets show that the proposed coding scheme achieves superior prediction performance over the state-of-the-art coding methods.
[ { "version": "v1", "created": "Fri, 18 Mar 2016 11:51:09 GMT" } ]
2016-03-21T00:00:00
[ [ "Zhou", "Joey Tianyi", "" ], [ "Tsang", "Ivor W.", "" ], [ "Ho", "Shen-Shyang", "" ], [ "Muller", "Klaus-Robert", "" ] ]
TITLE: N-ary Error Correcting Coding Scheme ABSTRACT: The coding matrix design plays a fundamental role in the prediction performance of the error correcting output codes (ECOC)-based multi-class task. {In many-class classification problems, e.g., fine-grained categorization, it is difficult to distinguish subtle between-class differences under existing coding schemes due to a limited choices of coding values.} In this paper, we investigate whether one can relax existing binary and ternary code design to $N$-ary code design to achieve better classification performance. {In particular, we present a novel $N$-ary coding scheme that decomposes the original multi-class problem into simpler multi-class subproblems, which is similar to applying a divide-and-conquer method.} The two main advantages of such a coding scheme are as follows: (i) the ability to construct more discriminative codes and (ii) the flexibility for the user to select the best $N$ for ECOC-based classification. We show empirically that the optimal $N$ (based on classification performance) lies in $[3, 10]$ with some trade-off in computational cost. Moreover, we provide theoretical insights on the dependency of the generalization error bound of an $N$-ary ECOC on the average base classifier generalization error and the minimum distance between any two codes constructed. Extensive experimental results on benchmark multi-class datasets show that the proposed coding scheme achieves superior prediction performance over the state-of-the-art coding methods.
no_new_dataset
0.939913
1507.04717
Alessandro Rudi
Alessandro Rudi, Raffaello Camoriano, Lorenzo Rosasco
Less is More: Nystr\"om Computational Regularization
updated version of NIPS 2015 (oral)
null
null
null
stat.ML cs.LG
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We study Nystr\"om type subsampling approaches to large scale kernel methods, and prove learning bounds in the statistical learning setting, where random sampling and high probability estimates are considered. In particular, we prove that these approaches can achieve optimal learning bounds, provided the subsampling level is suitably chosen. These results suggest a simple incremental variant of Nystr\"om Kernel Regularized Least Squares, where the subsampling level implements a form of computational regularization, in the sense that it controls at the same time regularization and computations. Extensive experimental analysis shows that the considered approach achieves state of the art performances on benchmark large scale datasets.
[ { "version": "v1", "created": "Thu, 16 Jul 2015 19:26:27 GMT" }, { "version": "v2", "created": "Tue, 21 Jul 2015 15:37:29 GMT" }, { "version": "v3", "created": "Mon, 5 Oct 2015 21:34:59 GMT" }, { "version": "v4", "created": "Thu, 5 Nov 2015 15:16:59 GMT" }, { "version": "v5", "created": "Mon, 7 Mar 2016 17:34:28 GMT" }, { "version": "v6", "created": "Thu, 17 Mar 2016 16:27:36 GMT" } ]
2016-03-18T00:00:00
[ [ "Rudi", "Alessandro", "" ], [ "Camoriano", "Raffaello", "" ], [ "Rosasco", "Lorenzo", "" ] ]
TITLE: Less is More: Nystr\"om Computational Regularization ABSTRACT: We study Nystr\"om type subsampling approaches to large scale kernel methods, and prove learning bounds in the statistical learning setting, where random sampling and high probability estimates are considered. In particular, we prove that these approaches can achieve optimal learning bounds, provided the subsampling level is suitably chosen. These results suggest a simple incremental variant of Nystr\"om Kernel Regularized Least Squares, where the subsampling level implements a form of computational regularization, in the sense that it controls at the same time regularization and computations. Extensive experimental analysis shows that the considered approach achieves state of the art performances on benchmark large scale datasets.
no_new_dataset
0.951006
1508.06073
Hilde Kuehne
Hilde Kuehne and Juergen Gall and Thomas Serre
Cooking in the kitchen: Recognizing and Segmenting Human Activities in Videos
15 pages, 12 figures
null
null
null
cs.CV
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
As research on action recognition matures, the focus is shifting away from categorizing basic task-oriented actions using hand-segmented video datasets to understanding complex goal-oriented daily human activities in real-world settings. Temporally structured models would seem obvious to tackle this set of problems, but so far, cases where these models have outperformed simpler unstructured bag-of-word types of models are scarce. With the increasing availability of large human activity datasets, combined with the development of novel feature coding techniques that yield more compact representations, it is time to revisit structured generative approaches. Here, we describe an end-to-end generative approach from the encoding of features to the structural modeling of complex human activities by applying Fisher vectors and temporal models for the analysis of video sequences. We systematically evaluate the proposed approach on several available datasets (ADL, MPIICooking, and Breakfast datasets) using a variety of performance metrics. Through extensive system evaluations, we demonstrate that combining compact video representations based on Fisher Vectors with HMM-based modeling yields very significant gains in accuracy and when properly trained with sufficient training samples, structured temporal models outperform unstructured bag-of-word types of models by a large margin on the tested performance metric.
[ { "version": "v1", "created": "Tue, 25 Aug 2015 08:59:46 GMT" }, { "version": "v2", "created": "Thu, 17 Mar 2016 10:04:21 GMT" } ]
2016-03-18T00:00:00
[ [ "Kuehne", "Hilde", "" ], [ "Gall", "Juergen", "" ], [ "Serre", "Thomas", "" ] ]
TITLE: Cooking in the kitchen: Recognizing and Segmenting Human Activities in Videos ABSTRACT: As research on action recognition matures, the focus is shifting away from categorizing basic task-oriented actions using hand-segmented video datasets to understanding complex goal-oriented daily human activities in real-world settings. Temporally structured models would seem obvious to tackle this set of problems, but so far, cases where these models have outperformed simpler unstructured bag-of-word types of models are scarce. With the increasing availability of large human activity datasets, combined with the development of novel feature coding techniques that yield more compact representations, it is time to revisit structured generative approaches. Here, we describe an end-to-end generative approach from the encoding of features to the structural modeling of complex human activities by applying Fisher vectors and temporal models for the analysis of video sequences. We systematically evaluate the proposed approach on several available datasets (ADL, MPIICooking, and Breakfast datasets) using a variety of performance metrics. Through extensive system evaluations, we demonstrate that combining compact video representations based on Fisher Vectors with HMM-based modeling yields very significant gains in accuracy and when properly trained with sufficient training samples, structured temporal models outperform unstructured bag-of-word types of models by a large margin on the tested performance metric.
no_new_dataset
0.941439
1509.01947
Hilde Kuehne
Hilde Kuehne and Juergen Gall and Thomas Serre
An end-to-end generative framework for video segmentation and recognition
Proc. of IEEE Winter Conference on Applications of Computer Vision (WACV), 2016
null
null
null
cs.CV
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We describe an end-to-end generative approach for the segmentation and recognition of human activities. In this approach, a visual representation based on reduced Fisher Vectors is combined with a structured temporal model for recognition. We show that the statistical properties of Fisher Vectors make them an especially suitable front-end for generative models such as Gaussian mixtures. The system is evaluated for both the recognition of complex activities as well as their parsing into action units. Using a variety of video datasets ranging from human cooking activities to animal behaviors, our experiments demonstrate that the resulting architecture outperforms state-of-the-art approaches for larger datasets, i.e. when sufficient amount of data is available for training structured generative models.
[ { "version": "v1", "created": "Mon, 7 Sep 2015 08:35:48 GMT" }, { "version": "v2", "created": "Thu, 17 Mar 2016 09:43:10 GMT" } ]
2016-03-18T00:00:00
[ [ "Kuehne", "Hilde", "" ], [ "Gall", "Juergen", "" ], [ "Serre", "Thomas", "" ] ]
TITLE: An end-to-end generative framework for video segmentation and recognition ABSTRACT: We describe an end-to-end generative approach for the segmentation and recognition of human activities. In this approach, a visual representation based on reduced Fisher Vectors is combined with a structured temporal model for recognition. We show that the statistical properties of Fisher Vectors make them an especially suitable front-end for generative models such as Gaussian mixtures. The system is evaluated for both the recognition of complex activities as well as their parsing into action units. Using a variety of video datasets ranging from human cooking activities to animal behaviors, our experiments demonstrate that the resulting architecture outperforms state-of-the-art approaches for larger datasets, i.e. when sufficient amount of data is available for training structured generative models.
no_new_dataset
0.952175
1511.02917
Vignesh Ramanathan
Vignesh Ramanathan and Jonathan Huang and Sami Abu-El-Haija and Alexander Gorban and Kevin Murphy and Li Fei-Fei
Detecting events and key actors in multi-person videos
Accepted for publication in CVPR'16
null
null
null
cs.CV cs.AI
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Multi-person event recognition is a challenging task, often with many people active in the scene but only a small subset contributing to an actual event. In this paper, we propose a model which learns to detect events in such videos while automatically "attending" to the people responsible for the event. Our model does not use explicit annotations regarding who or where those people are during training and testing. In particular, we track people in videos and use a recurrent neural network (RNN) to represent the track features. We learn time-varying attention weights to combine these features at each time-instant. The attended features are then processed using another RNN for event detection/classification. Since most video datasets with multiple people are restricted to a small number of videos, we also collected a new basketball dataset comprising 257 basketball games with 14K event annotations corresponding to 11 event classes. Our model outperforms state-of-the-art methods for both event classification and detection on this new dataset. Additionally, we show that the attention mechanism is able to consistently localize the relevant players.
[ { "version": "v1", "created": "Mon, 9 Nov 2015 22:30:19 GMT" }, { "version": "v2", "created": "Thu, 17 Mar 2016 00:02:03 GMT" } ]
2016-03-18T00:00:00
[ [ "Ramanathan", "Vignesh", "" ], [ "Huang", "Jonathan", "" ], [ "Abu-El-Haija", "Sami", "" ], [ "Gorban", "Alexander", "" ], [ "Murphy", "Kevin", "" ], [ "Fei-Fei", "Li", "" ] ]
TITLE: Detecting events and key actors in multi-person videos ABSTRACT: Multi-person event recognition is a challenging task, often with many people active in the scene but only a small subset contributing to an actual event. In this paper, we propose a model which learns to detect events in such videos while automatically "attending" to the people responsible for the event. Our model does not use explicit annotations regarding who or where those people are during training and testing. In particular, we track people in videos and use a recurrent neural network (RNN) to represent the track features. We learn time-varying attention weights to combine these features at each time-instant. The attended features are then processed using another RNN for event detection/classification. Since most video datasets with multiple people are restricted to a small number of videos, we also collected a new basketball dataset comprising 257 basketball games with 14K event annotations corresponding to 11 event classes. Our model outperforms state-of-the-art methods for both event classification and detection on this new dataset. Additionally, we show that the attention mechanism is able to consistently localize the relevant players.
new_dataset
0.963746
1602.02830
Itay Hubara
Matthieu Courbariaux, Itay Hubara, Daniel Soudry, Ran El-Yaniv and Yoshua Bengio
Binarized Neural Networks: Training Deep Neural Networks with Weights and Activations Constrained to +1 or -1
11 pages and 3 figures
null
null
null
cs.LG
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We introduce a method to train Binarized Neural Networks (BNNs) - neural networks with binary weights and activations at run-time. At training-time the binary weights and activations are used for computing the parameters gradients. During the forward pass, BNNs drastically reduce memory size and accesses, and replace most arithmetic operations with bit-wise operations, which is expected to substantially improve power-efficiency. To validate the effectiveness of BNNs we conduct two sets of experiments on the Torch7 and Theano frameworks. On both, BNNs achieved nearly state-of-the-art results over the MNIST, CIFAR-10 and SVHN datasets. Last but not least, we wrote a binary matrix multiplication GPU kernel with which it is possible to run our MNIST BNN 7 times faster than with an unoptimized GPU kernel, without suffering any loss in classification accuracy. The code for training and running our BNNs is available on-line.
[ { "version": "v1", "created": "Tue, 9 Feb 2016 01:01:59 GMT" }, { "version": "v2", "created": "Mon, 29 Feb 2016 21:26:53 GMT" }, { "version": "v3", "created": "Thu, 17 Mar 2016 14:54:25 GMT" } ]
2016-03-18T00:00:00
[ [ "Courbariaux", "Matthieu", "" ], [ "Hubara", "Itay", "" ], [ "Soudry", "Daniel", "" ], [ "El-Yaniv", "Ran", "" ], [ "Bengio", "Yoshua", "" ] ]
TITLE: Binarized Neural Networks: Training Deep Neural Networks with Weights and Activations Constrained to +1 or -1 ABSTRACT: We introduce a method to train Binarized Neural Networks (BNNs) - neural networks with binary weights and activations at run-time. At training-time the binary weights and activations are used for computing the parameters gradients. During the forward pass, BNNs drastically reduce memory size and accesses, and replace most arithmetic operations with bit-wise operations, which is expected to substantially improve power-efficiency. To validate the effectiveness of BNNs we conduct two sets of experiments on the Torch7 and Theano frameworks. On both, BNNs achieved nearly state-of-the-art results over the MNIST, CIFAR-10 and SVHN datasets. Last but not least, we wrote a binary matrix multiplication GPU kernel with which it is possible to run our MNIST BNN 7 times faster than with an unoptimized GPU kernel, without suffering any loss in classification accuracy. The code for training and running our BNNs is available on-line.
no_new_dataset
0.945045
1603.05422
Panagiotis Bouros
Panagiotis Bouros, Nikos Mamoulis, Shen Ge and Manolis Terrovitis
Set Containment Join Revisited
To appear at the Knowledge and Information Systems journal (KAIS)
null
10.1007/s10115-015-0895-7
null
cs.DB
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Given two collections of set objects $R$ and $S$, the $R \bowtie_{\subseteq} S$ set containment join returns all object pairs $(r, s) \in R \times S$ such that $r \subseteq s$. Besides being a basic operator in all modern data management systems with a wide range of applications, the join can be used to evaluate complex SQL queries based on relational division and as a module of data mining algorithms. The state-of-the-art algorithm for set containment joins (PRETTI) builds an inverted index on the right-hand collection $S$ and a prefix tree on the left-hand collection $R$ that groups set objects with common prefixes and thus, avoids redundant processing. In this paper, we present a framework which improves PRETTI in two directions. First, we limit the prefix tree construction by proposing an adaptive methodology based on a cost model; this way, we can greatly reduce the space and time cost of the join. Second, we partition the objects of each collection based on their first contained item, assuming that the set objects are internally sorted. We show that we can process the partitions and evaluate the join while building the prefix tree and the inverted index progressively. This allows us to significantly reduce not only the join cost, but also the maximum memory requirements during the join. An experimental evaluation using both real and synthetic datasets shows that our framework outperforms PRETTI by a wide margin.
[ { "version": "v1", "created": "Thu, 17 Mar 2016 10:47:48 GMT" } ]
2016-03-18T00:00:00
[ [ "Bouros", "Panagiotis", "" ], [ "Mamoulis", "Nikos", "" ], [ "Ge", "Shen", "" ], [ "Terrovitis", "Manolis", "" ] ]
TITLE: Set Containment Join Revisited ABSTRACT: Given two collections of set objects $R$ and $S$, the $R \bowtie_{\subseteq} S$ set containment join returns all object pairs $(r, s) \in R \times S$ such that $r \subseteq s$. Besides being a basic operator in all modern data management systems with a wide range of applications, the join can be used to evaluate complex SQL queries based on relational division and as a module of data mining algorithms. The state-of-the-art algorithm for set containment joins (PRETTI) builds an inverted index on the right-hand collection $S$ and a prefix tree on the left-hand collection $R$ that groups set objects with common prefixes and thus, avoids redundant processing. In this paper, we present a framework which improves PRETTI in two directions. First, we limit the prefix tree construction by proposing an adaptive methodology based on a cost model; this way, we can greatly reduce the space and time cost of the join. Second, we partition the objects of each collection based on their first contained item, assuming that the set objects are internally sorted. We show that we can process the partitions and evaluate the join while building the prefix tree and the inverted index progressively. This allows us to significantly reduce not only the join cost, but also the maximum memory requirements during the join. An experimental evaluation using both real and synthetic datasets shows that our framework outperforms PRETTI by a wide margin.
no_new_dataset
0.943556
1603.05435
Rajeev Rajan
Rajeev Rajan and Hema A. Murthy
Modified Group Delay Based MultiPitch Estimation in Co-Channel Speech
null
null
null
null
cs.SD
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Phase processing has been replaced by group delay processing for the extraction of source and system parameters from speech. Group delay functions are ill-behaved when the transfer function has zeros that are close to unit circle in the z-domain. The modified group delay function addresses this problem and has been successfully used for formant and monopitch estimation. In this paper, modified group delay functions are used for multipitch estimation in concurrent speech. The power spectrum of the speech is first flattened in order to annihilate the system characteristics, while retaining the source characteristics. Group delay analysis on this flattened spectrum picks the predominant pitch in the first pass and a comb filter is used to filter out the estimated pitch along with its harmonics. The residual spectrum is again analyzed for the next candidate pitch estimate in the second pass. The final pitch trajectories of the constituent speech utterances are formed using pitch grouping and post processing techniques. The performance of the proposed algorithm was evaluated on standard datasets using two metrics; pitch accuracy and standard deviation of fine pitch error. Our results show that the proposed algorithm is a promising pitch detection method in multipitch environment for real speech recordings.
[ { "version": "v1", "created": "Thu, 17 Mar 2016 11:35:09 GMT" } ]
2016-03-18T00:00:00
[ [ "Rajan", "Rajeev", "" ], [ "Murthy", "Hema A.", "" ] ]
TITLE: Modified Group Delay Based MultiPitch Estimation in Co-Channel Speech ABSTRACT: Phase processing has been replaced by group delay processing for the extraction of source and system parameters from speech. Group delay functions are ill-behaved when the transfer function has zeros that are close to unit circle in the z-domain. The modified group delay function addresses this problem and has been successfully used for formant and monopitch estimation. In this paper, modified group delay functions are used for multipitch estimation in concurrent speech. The power spectrum of the speech is first flattened in order to annihilate the system characteristics, while retaining the source characteristics. Group delay analysis on this flattened spectrum picks the predominant pitch in the first pass and a comb filter is used to filter out the estimated pitch along with its harmonics. The residual spectrum is again analyzed for the next candidate pitch estimate in the second pass. The final pitch trajectories of the constituent speech utterances are formed using pitch grouping and post processing techniques. The performance of the proposed algorithm was evaluated on standard datasets using two metrics; pitch accuracy and standard deviation of fine pitch error. Our results show that the proposed algorithm is a promising pitch detection method in multipitch environment for real speech recordings.
no_new_dataset
0.95222
1603.05462
Aanjhan Ranganathan
Aanjhan Ranganathan, Hildur \'Olafsd\'ottir, Srdjan Capkun
SPREE: Spoofing Resistant GPS Receiver
null
null
null
null
cs.CR
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Global Positioning System (GPS) is used ubiquitously in a wide variety of applications ranging from navigation and tracking to modern smart grids and communication networks. However, it has been demonstrated that modern GPS receivers are vulnerable to signal spoofing attacks. For example, today it is possible to change the course of a ship or force a drone to land in an hostile area by simply spoofing GPS signals. Several countermeasures have been proposed in the past to detect GPS spoofing attacks. These countermeasures offer protection only against naive attackers. They are incapable of detecting strong attackers such as those capable of seamlessly taking over a GPS receiver, which is currently receiving legitimate satellite signals, and spoofing them to an arbitrary location. Also, there is no hardware platform that can be used to compare and evaluate the effectiveness of existing countermeasures in real-world scenarios. In this work, we present SPREE, which is, to the best of our knowledge, the first GPS receiver capable of detecting all spoofing attacks described in literature. Our novel spoofing detection technique called auxiliary peak tracking enables detection of even a strong attacker capable of executing the seamless takeover attack. We implement and evaluate our receiver against three different sets of GPS signal traces and show that SPREE constrains even a strong attacker (capable of seamless takeover attack) from spoofing the receiver to a location not more than 1 km away from its true location. This is a significant improvement over modern GPS receivers that can be spoofed to any arbitrary location. Finally, we release our implementation and datasets to the community for further research and development.
[ { "version": "v1", "created": "Thu, 17 Mar 2016 13:00:41 GMT" } ]
2016-03-18T00:00:00
[ [ "Ranganathan", "Aanjhan", "" ], [ "Ólafsdóttir", "Hildur", "" ], [ "Capkun", "Srdjan", "" ] ]
TITLE: SPREE: Spoofing Resistant GPS Receiver ABSTRACT: Global Positioning System (GPS) is used ubiquitously in a wide variety of applications ranging from navigation and tracking to modern smart grids and communication networks. However, it has been demonstrated that modern GPS receivers are vulnerable to signal spoofing attacks. For example, today it is possible to change the course of a ship or force a drone to land in an hostile area by simply spoofing GPS signals. Several countermeasures have been proposed in the past to detect GPS spoofing attacks. These countermeasures offer protection only against naive attackers. They are incapable of detecting strong attackers such as those capable of seamlessly taking over a GPS receiver, which is currently receiving legitimate satellite signals, and spoofing them to an arbitrary location. Also, there is no hardware platform that can be used to compare and evaluate the effectiveness of existing countermeasures in real-world scenarios. In this work, we present SPREE, which is, to the best of our knowledge, the first GPS receiver capable of detecting all spoofing attacks described in literature. Our novel spoofing detection technique called auxiliary peak tracking enables detection of even a strong attacker capable of executing the seamless takeover attack. We implement and evaluate our receiver against three different sets of GPS signal traces and show that SPREE constrains even a strong attacker (capable of seamless takeover attack) from spoofing the receiver to a location not more than 1 km away from its true location. This is a significant improvement over modern GPS receivers that can be spoofed to any arbitrary location. Finally, we release our implementation and datasets to the community for further research and development.
no_new_dataset
0.921428
1603.05583
L\'aszl\'o Gyarmati
Laszlo Gyarmati, Mohamed Hefeeda
Analyzing In-Game Movements of Soccer Players at Scale
MIT Sloan Sports Analytics Conference 2016
null
null
null
cs.OH stat.AP
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
It is challenging to get access to datasets related to the physical performance of soccer players. The teams consider such information highly confidential, especially if it covers in-game performance.Hence, most of the analysis and evaluation of the players' performance do not contain much information on the physical aspect of the game, creating a blindspot in performance analysis. We propose a novel method to solve this issue by deriving movement characteristics of soccer players. We use event-based datasets from data provider companies covering 50+ soccer leagues allowing us to analyze the movement profiles of potentially tens of thousands of players without any major investment. Our methodology does not require expensive, dedicated player tracking system deployed in the stadium. We also compute the similarity of the players based on their movement characteristics and as such identify potential candidates who may be able to replace a given player. Finally, we quantify the uniqueness and consistency of players in terms of their in-game movements. Our study is the first of its kind that focuses on the movements of soccer players at scale, while it derives novel, actionable insights for the soccer industry from event-based datasets.
[ { "version": "v1", "created": "Fri, 11 Mar 2016 23:54:55 GMT" } ]
2016-03-18T00:00:00
[ [ "Gyarmati", "Laszlo", "" ], [ "Hefeeda", "Mohamed", "" ] ]
TITLE: Analyzing In-Game Movements of Soccer Players at Scale ABSTRACT: It is challenging to get access to datasets related to the physical performance of soccer players. The teams consider such information highly confidential, especially if it covers in-game performance.Hence, most of the analysis and evaluation of the players' performance do not contain much information on the physical aspect of the game, creating a blindspot in performance analysis. We propose a novel method to solve this issue by deriving movement characteristics of soccer players. We use event-based datasets from data provider companies covering 50+ soccer leagues allowing us to analyze the movement profiles of potentially tens of thousands of players without any major investment. Our methodology does not require expensive, dedicated player tracking system deployed in the stadium. We also compute the similarity of the players based on their movement characteristics and as such identify potential candidates who may be able to replace a given player. Finally, we quantify the uniqueness and consistency of players in terms of their in-game movements. Our study is the first of its kind that focuses on the movements of soccer players at scale, while it derives novel, actionable insights for the soccer industry from event-based datasets.
no_new_dataset
0.942507
1603.05600
Roozbeh Mottaghi
Roozbeh Mottaghi, Mohammad Rastegari, Abhinav Gupta, Ali Farhadi
"What happens if..." Learning to Predict the Effect of Forces in Images
null
null
null
null
cs.CV
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
What happens if one pushes a cup sitting on a table toward the edge of the table? How about pushing a desk against a wall? In this paper, we study the problem of understanding the movements of objects as a result of applying external forces to them. For a given force vector applied to a specific location in an image, our goal is to predict long-term sequential movements caused by that force. Doing so entails reasoning about scene geometry, objects, their attributes, and the physical rules that govern the movements of objects. We design a deep neural network model that learns long-term sequential dependencies of object movements while taking into account the geometry and appearance of the scene by combining Convolutional and Recurrent Neural Networks. Training our model requires a large-scale dataset of object movements caused by external forces. To build a dataset of forces in scenes, we reconstructed all images in SUN RGB-D dataset in a physics simulator to estimate the physical movements of objects caused by external forces applied to them. Our Forces in Scenes (ForScene) dataset contains 10,335 images in which a variety of external forces are applied to different types of objects resulting in more than 65,000 object movements represented in 3D. Our experimental evaluations show that the challenging task of predicting long-term movements of objects as their reaction to external forces is possible from a single image.
[ { "version": "v1", "created": "Thu, 17 Mar 2016 18:12:33 GMT" } ]
2016-03-18T00:00:00
[ [ "Mottaghi", "Roozbeh", "" ], [ "Rastegari", "Mohammad", "" ], [ "Gupta", "Abhinav", "" ], [ "Farhadi", "Ali", "" ] ]
TITLE: "What happens if..." Learning to Predict the Effect of Forces in Images ABSTRACT: What happens if one pushes a cup sitting on a table toward the edge of the table? How about pushing a desk against a wall? In this paper, we study the problem of understanding the movements of objects as a result of applying external forces to them. For a given force vector applied to a specific location in an image, our goal is to predict long-term sequential movements caused by that force. Doing so entails reasoning about scene geometry, objects, their attributes, and the physical rules that govern the movements of objects. We design a deep neural network model that learns long-term sequential dependencies of object movements while taking into account the geometry and appearance of the scene by combining Convolutional and Recurrent Neural Networks. Training our model requires a large-scale dataset of object movements caused by external forces. To build a dataset of forces in scenes, we reconstructed all images in SUN RGB-D dataset in a physics simulator to estimate the physical movements of objects caused by external forces applied to them. Our Forces in Scenes (ForScene) dataset contains 10,335 images in which a variety of external forces are applied to different types of objects resulting in more than 65,000 object movements represented in 3D. Our experimental evaluations show that the challenging task of predicting long-term movements of objects as their reaction to external forces is possible from a single image.
new_dataset
0.964254
1603.04871
Zhicheng Yan
Zhicheng Yan, Hao Zhang, Yangqing Jia, Thomas Breuel, Yizhou Yu
Combining the Best of Convolutional Layers and Recurrent Layers: A Hybrid Network for Semantic Segmentation
14 pages
null
null
null
cs.CV
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
State-of-the-art results of semantic segmentation are established by Fully Convolutional neural Networks (FCNs). FCNs rely on cascaded convolutional and pooling layers to gradually enlarge the receptive fields of neurons, resulting in an indirect way of modeling the distant contextual dependence. In this work, we advocate the use of spatially recurrent layers (i.e. ReNet layers) which directly capture global contexts and lead to improved feature representations. We demonstrate the effectiveness of ReNet layers by building a Naive deep ReNet (N-ReNet), which achieves competitive performance on Stanford Background dataset. Furthermore, we integrate ReNet layers with FCNs, and develop a novel Hybrid deep ReNet (H-ReNet). It enjoys a few remarkable properties, including full-image receptive fields, end-to-end training, and efficient network execution. On the PASCAL VOC 2012 benchmark, the H-ReNet improves the results of state-of-the-art approaches Piecewise, CRFasRNN and DeepParsing by 3.6%, 2.3% and 0.2%, respectively, and achieves the highest IoUs for 13 out of the 20 object classes.
[ { "version": "v1", "created": "Tue, 15 Mar 2016 20:10:48 GMT" } ]
2016-03-17T00:00:00
[ [ "Yan", "Zhicheng", "" ], [ "Zhang", "Hao", "" ], [ "Jia", "Yangqing", "" ], [ "Breuel", "Thomas", "" ], [ "Yu", "Yizhou", "" ] ]
TITLE: Combining the Best of Convolutional Layers and Recurrent Layers: A Hybrid Network for Semantic Segmentation ABSTRACT: State-of-the-art results of semantic segmentation are established by Fully Convolutional neural Networks (FCNs). FCNs rely on cascaded convolutional and pooling layers to gradually enlarge the receptive fields of neurons, resulting in an indirect way of modeling the distant contextual dependence. In this work, we advocate the use of spatially recurrent layers (i.e. ReNet layers) which directly capture global contexts and lead to improved feature representations. We demonstrate the effectiveness of ReNet layers by building a Naive deep ReNet (N-ReNet), which achieves competitive performance on Stanford Background dataset. Furthermore, we integrate ReNet layers with FCNs, and develop a novel Hybrid deep ReNet (H-ReNet). It enjoys a few remarkable properties, including full-image receptive fields, end-to-end training, and efficient network execution. On the PASCAL VOC 2012 benchmark, the H-ReNet improves the results of state-of-the-art approaches Piecewise, CRFasRNN and DeepParsing by 3.6%, 2.3% and 0.2%, respectively, and achieves the highest IoUs for 13 out of the 20 object classes.
no_new_dataset
0.952131
1603.04918
Shahzad Bhatti
Shahzad Bhatti, Carolyn Beck, Angelia Nedic
Data Clustering and Graph Partitioning via Simulated Mixing
28 pages
null
null
null
cs.LG stat.ML
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Spectral clustering approaches have led to well-accepted algorithms for finding accurate clusters in a given dataset. However, their application to large-scale datasets has been hindered by computational complexity of eigenvalue decompositions. Several algorithms have been proposed in the recent past to accelerate spectral clustering, however they compromise on the accuracy of the spectral clustering to achieve faster speed. In this paper, we propose a novel spectral clustering algorithm based on a mixing process on a graph. Unlike the existing spectral clustering algorithms, our algorithm does not require computing eigenvectors. Specifically, it finds the equivalent of a linear combination of eigenvectors of the normalized similarity matrix weighted with corresponding eigenvalues. This linear combination is then used to partition the dataset into meaningful clusters. Simulations on real datasets show that partitioning datasets based on such linear combinations of eigenvectors achieves better accuracy than standard spectral clustering methods as the number of clusters increase. Our algorithm can easily be implemented in a distributed setting.
[ { "version": "v1", "created": "Tue, 15 Mar 2016 23:06:19 GMT" } ]
2016-03-17T00:00:00
[ [ "Bhatti", "Shahzad", "" ], [ "Beck", "Carolyn", "" ], [ "Nedic", "Angelia", "" ] ]
TITLE: Data Clustering and Graph Partitioning via Simulated Mixing ABSTRACT: Spectral clustering approaches have led to well-accepted algorithms for finding accurate clusters in a given dataset. However, their application to large-scale datasets has been hindered by computational complexity of eigenvalue decompositions. Several algorithms have been proposed in the recent past to accelerate spectral clustering, however they compromise on the accuracy of the spectral clustering to achieve faster speed. In this paper, we propose a novel spectral clustering algorithm based on a mixing process on a graph. Unlike the existing spectral clustering algorithms, our algorithm does not require computing eigenvectors. Specifically, it finds the equivalent of a linear combination of eigenvectors of the normalized similarity matrix weighted with corresponding eigenvalues. This linear combination is then used to partition the dataset into meaningful clusters. Simulations on real datasets show that partitioning datasets based on such linear combinations of eigenvectors achieves better accuracy than standard spectral clustering methods as the number of clusters increase. Our algorithm can easily be implemented in a distributed setting.
no_new_dataset
0.950549
1603.05015
Ravi Garg
Ravi Garg, Anders Eriksson and Ian Reid
Non-linear Dimensionality Regularizer for Solving Inverse Problems
null
null
null
null
cs.CV
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Consider an ill-posed inverse problem of estimating causal factors from observations, one of which is known to lie near some (un- known) low-dimensional, non-linear manifold expressed by a predefined Mercer-kernel. Solving this problem requires simultaneous estimation of these factors and learning the low-dimensional representation for them. In this work, we introduce a novel non-linear dimensionality regulariza- tion technique for solving such problems without pre-training. We re-formulate Kernel-PCA as an energy minimization problem in which low dimensionality constraints are introduced as regularization terms in the energy. To the best of our knowledge, ours is the first at- tempt to create a dimensionality regularizer in the KPCA framework. Our approach relies on robustly penalizing the rank of the recovered fac- tors directly in the implicit feature space to create their low-dimensional approximations in closed form. Our approach performs robust KPCA in the presence of missing data and noise. We demonstrate state-of-the-art results on predicting missing entries in the standard oil flow dataset. Additionally, we evaluate our method on the challenging problem of Non-Rigid Structure from Motion and our approach delivers promising results on CMU mocap dataset despite the presence of significant occlusions and noise.
[ { "version": "v1", "created": "Wed, 16 Mar 2016 10:04:38 GMT" } ]
2016-03-17T00:00:00
[ [ "Garg", "Ravi", "" ], [ "Eriksson", "Anders", "" ], [ "Reid", "Ian", "" ] ]
TITLE: Non-linear Dimensionality Regularizer for Solving Inverse Problems ABSTRACT: Consider an ill-posed inverse problem of estimating causal factors from observations, one of which is known to lie near some (un- known) low-dimensional, non-linear manifold expressed by a predefined Mercer-kernel. Solving this problem requires simultaneous estimation of these factors and learning the low-dimensional representation for them. In this work, we introduce a novel non-linear dimensionality regulariza- tion technique for solving such problems without pre-training. We re-formulate Kernel-PCA as an energy minimization problem in which low dimensionality constraints are introduced as regularization terms in the energy. To the best of our knowledge, ours is the first at- tempt to create a dimensionality regularizer in the KPCA framework. Our approach relies on robustly penalizing the rank of the recovered fac- tors directly in the implicit feature space to create their low-dimensional approximations in closed form. Our approach performs robust KPCA in the presence of missing data and noise. We demonstrate state-of-the-art results on predicting missing entries in the standard oil flow dataset. Additionally, we evaluate our method on the challenging problem of Non-Rigid Structure from Motion and our approach delivers promising results on CMU mocap dataset despite the presence of significant occlusions and noise.
no_new_dataset
0.944536
1603.05152
Kleanthis Malialis
Kleanthis Malialis and Jun Wang and Gary Brooks and George Frangou
Feature Selection as a Multiagent Coordination Problem
AAMAS-16 Workshop on Adaptive and Learning Agents (ALA-16)
null
null
null
cs.LG stat.ML
http://creativecommons.org/licenses/by/4.0/
Datasets with hundreds to tens of thousands features is the new norm. Feature selection constitutes a central problem in machine learning, where the aim is to derive a representative set of features from which to construct a classification (or prediction) model for a specific task. Our experimental study involves microarray gene expression datasets, these are high-dimensional and noisy datasets that contain genetic data typically used for distinguishing between benign or malicious tissues or classifying different types of cancer. In this paper, we formulate feature selection as a multiagent coordination problem and propose a novel feature selection method using multiagent reinforcement learning. The central idea of the proposed approach is to "assign" a reinforcement learning agent to each feature where each agent learns to control a single feature, we refer to this approach as MARL. Applying this to microarray datasets creates an enormous multiagent coordination problem between thousands of learning agents. To address the scalability challenge we apply a form of reward shaping called CLEAN rewards. We compare in total nine feature selection methods, including state-of-the-art methods, and show that the proposed method using CLEAN rewards can significantly scale-up, thus outperforming the rest of learning-based methods. We further show that a hybrid variant of MARL achieves the best overall performance.
[ { "version": "v1", "created": "Wed, 16 Mar 2016 15:49:37 GMT" } ]
2016-03-17T00:00:00
[ [ "Malialis", "Kleanthis", "" ], [ "Wang", "Jun", "" ], [ "Brooks", "Gary", "" ], [ "Frangou", "George", "" ] ]
TITLE: Feature Selection as a Multiagent Coordination Problem ABSTRACT: Datasets with hundreds to tens of thousands features is the new norm. Feature selection constitutes a central problem in machine learning, where the aim is to derive a representative set of features from which to construct a classification (or prediction) model for a specific task. Our experimental study involves microarray gene expression datasets, these are high-dimensional and noisy datasets that contain genetic data typically used for distinguishing between benign or malicious tissues or classifying different types of cancer. In this paper, we formulate feature selection as a multiagent coordination problem and propose a novel feature selection method using multiagent reinforcement learning. The central idea of the proposed approach is to "assign" a reinforcement learning agent to each feature where each agent learns to control a single feature, we refer to this approach as MARL. Applying this to microarray datasets creates an enormous multiagent coordination problem between thousands of learning agents. To address the scalability challenge we apply a form of reward shaping called CLEAN rewards. We compare in total nine feature selection methods, including state-of-the-art methods, and show that the proposed method using CLEAN rewards can significantly scale-up, thus outperforming the rest of learning-based methods. We further show that a hybrid variant of MARL achieves the best overall performance.
no_new_dataset
0.94625
1603.05191
Martin Tak\'a\v{c}
Chenxin Ma and Martin Tak\'a\v{c}
Distributed Inexact Damped Newton Method: Data Partitioning and Load-Balancing
null
null
null
null
cs.LG math.OC
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
In this paper we study inexact dumped Newton method implemented in a distributed environment. We start with an original DiSCO algorithm [Communication-Efficient Distributed Optimization of Self-Concordant Empirical Loss, Yuchen Zhang and Lin Xiao, 2015]. We will show that this algorithm may not scale well and propose an algorithmic modifications which will lead to less communications, better load-balancing and more efficient computation. We perform numerical experiments with an regularized empirical loss minimization instance described by a 273GB dataset.
[ { "version": "v1", "created": "Wed, 16 Mar 2016 17:50:33 GMT" } ]
2016-03-17T00:00:00
[ [ "Ma", "Chenxin", "" ], [ "Takáč", "Martin", "" ] ]
TITLE: Distributed Inexact Damped Newton Method: Data Partitioning and Load-Balancing ABSTRACT: In this paper we study inexact dumped Newton method implemented in a distributed environment. We start with an original DiSCO algorithm [Communication-Efficient Distributed Optimization of Self-Concordant Empirical Loss, Yuchen Zhang and Lin Xiao, 2015]. We will show that this algorithm may not scale well and propose an algorithmic modifications which will lead to less communications, better load-balancing and more efficient computation. We perform numerical experiments with an regularized empirical loss minimization instance described by a 273GB dataset.
no_new_dataset
0.555808
1511.04960
Mohammad Najafi
Mohammad Najafi, Sarah Taghavi Namin, Mathieu Salzmann, Lars Petersson
Sample and Filter: Nonparametric Scene Parsing via Efficient Filtering
Please refer to the CVPR-2016 version of this manuscript
null
null
null
cs.CV
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Scene parsing has attracted a lot of attention in computer vision. While parametric models have proven effective for this task, they cannot easily incorporate new training data. By contrast, nonparametric approaches, which bypass any learning phase and directly transfer the labels from the training data to the query images, can readily exploit new labeled samples as they become available. Unfortunately, because of the computational cost of their label transfer procedures, state-of-the-art nonparametric methods typically filter out most training images to only keep a few relevant ones to label the query. As such, these methods throw away many images that still contain valuable information and generally obtain an unbalanced set of labeled samples. In this paper, we introduce a nonparametric approach to scene parsing that follows a sample-and-filter strategy. More specifically, we propose to sample labeled superpixels according to an image similarity score, which allows us to obtain a balanced set of samples. We then formulate label transfer as an efficient filtering procedure, which lets us exploit more labeled samples than existing techniques. Our experiments evidence the benefits of our approach over state-of-the-art nonparametric methods on two benchmark datasets.
[ { "version": "v1", "created": "Mon, 16 Nov 2015 14:07:47 GMT" }, { "version": "v2", "created": "Tue, 15 Mar 2016 01:29:03 GMT" } ]
2016-03-16T00:00:00
[ [ "Najafi", "Mohammad", "" ], [ "Namin", "Sarah Taghavi", "" ], [ "Salzmann", "Mathieu", "" ], [ "Petersson", "Lars", "" ] ]
TITLE: Sample and Filter: Nonparametric Scene Parsing via Efficient Filtering ABSTRACT: Scene parsing has attracted a lot of attention in computer vision. While parametric models have proven effective for this task, they cannot easily incorporate new training data. By contrast, nonparametric approaches, which bypass any learning phase and directly transfer the labels from the training data to the query images, can readily exploit new labeled samples as they become available. Unfortunately, because of the computational cost of their label transfer procedures, state-of-the-art nonparametric methods typically filter out most training images to only keep a few relevant ones to label the query. As such, these methods throw away many images that still contain valuable information and generally obtain an unbalanced set of labeled samples. In this paper, we introduce a nonparametric approach to scene parsing that follows a sample-and-filter strategy. More specifically, we propose to sample labeled superpixels according to an image similarity score, which allows us to obtain a balanced set of samples. We then formulate label transfer as an efficient filtering procedure, which lets us exploit more labeled samples than existing techniques. Our experiments evidence the benefits of our approach over state-of-the-art nonparametric methods on two benchmark datasets.
no_new_dataset
0.948298
1601.04155
Zhangyang Wang
Zhangyang Wang, Shiyu Chang, Florin Dolcos, Diane Beck, Ding Liu, and Thomas S. Huang
Brain-Inspired Deep Networks for Image Aesthetics Assessment
null
null
null
null
cs.CV cs.LG cs.NE
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Image aesthetics assessment has been challenging due to its subjective nature. Inspired by the scientific advances in the human visual perception and neuroaesthetics, we design Brain-Inspired Deep Networks (BDN) for this task. BDN first learns attributes through the parallel supervised pathways, on a variety of selected feature dimensions. A high-level synthesis network is trained to associate and transform those attributes into the overall aesthetics rating. We then extend BDN to predicting the distribution of human ratings, since aesthetics ratings are often subjective. Another highlight is our first-of-its-kind study of label-preserving transformations in the context of aesthetics assessment, which leads to an effective data augmentation approach. Experimental results on the AVA dataset show that our biological inspired and task-specific BDN model gains significantly performance improvement, compared to other state-of-the-art models with the same or higher parameter capacity.
[ { "version": "v1", "created": "Sat, 16 Jan 2016 10:59:40 GMT" }, { "version": "v2", "created": "Tue, 15 Mar 2016 03:46:27 GMT" } ]
2016-03-16T00:00:00
[ [ "Wang", "Zhangyang", "" ], [ "Chang", "Shiyu", "" ], [ "Dolcos", "Florin", "" ], [ "Beck", "Diane", "" ], [ "Liu", "Ding", "" ], [ "Huang", "Thomas S.", "" ] ]
TITLE: Brain-Inspired Deep Networks for Image Aesthetics Assessment ABSTRACT: Image aesthetics assessment has been challenging due to its subjective nature. Inspired by the scientific advances in the human visual perception and neuroaesthetics, we design Brain-Inspired Deep Networks (BDN) for this task. BDN first learns attributes through the parallel supervised pathways, on a variety of selected feature dimensions. A high-level synthesis network is trained to associate and transform those attributes into the overall aesthetics rating. We then extend BDN to predicting the distribution of human ratings, since aesthetics ratings are often subjective. Another highlight is our first-of-its-kind study of label-preserving transformations in the context of aesthetics assessment, which leads to an effective data augmentation approach. Experimental results on the AVA dataset show that our biological inspired and task-specific BDN model gains significantly performance improvement, compared to other state-of-the-art models with the same or higher parameter capacity.
no_new_dataset
0.947962