id
stringlengths
9
16
submitter
stringlengths
3
64
authors
stringlengths
5
6.63k
title
stringlengths
7
245
comments
stringlengths
1
482
journal-ref
stringlengths
4
382
doi
stringlengths
9
151
report-no
stringclasses
984 values
categories
stringlengths
5
108
license
stringclasses
9 values
abstract
stringlengths
83
3.41k
versions
listlengths
1
20
update_date
timestamp[s]date
2007-05-23 00:00:00
2025-04-11 00:00:00
authors_parsed
sequencelengths
1
427
prompt
stringlengths
166
3.49k
label
stringclasses
2 values
prob
float64
0.5
0.98
1606.09367
Sepehr Valipour
Sepehr Valipour, Mennatullah Siam, Eleni Stroulia, Martin Jagersand
Parking Stall Vacancy Indicator System Based on Deep Convolutional Neural Networks
null
null
null
null
cs.CV
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Parking management systems, and vacancy-indication services in particular, can play a valuable role in reducing traffic and energy waste in large cities. Visual detection methods represent a cost-effective option, since they can take advantage of hardware usually already available in many parking lots, namely cameras. However, visual detection methods can be fragile and not easily generalizable. In this paper, we present a robust detection algorithm based on deep convolutional neural networks. We implemented and tested our algorithm on a large baseline dataset, and also on a set of image feeds from actual cameras already installed in parking lots. We have developed a fully functional system, from server-side image analysis to front-end user interface, to demonstrate the practicality of our method.
[ { "version": "v1", "created": "Thu, 30 Jun 2016 06:57:11 GMT" } ]
2016-07-01T00:00:00
[ [ "Valipour", "Sepehr", "" ], [ "Siam", "Mennatullah", "" ], [ "Stroulia", "Eleni", "" ], [ "Jagersand", "Martin", "" ] ]
TITLE: Parking Stall Vacancy Indicator System Based on Deep Convolutional Neural Networks ABSTRACT: Parking management systems, and vacancy-indication services in particular, can play a valuable role in reducing traffic and energy waste in large cities. Visual detection methods represent a cost-effective option, since they can take advantage of hardware usually already available in many parking lots, namely cameras. However, visual detection methods can be fragile and not easily generalizable. In this paper, we present a robust detection algorithm based on deep convolutional neural networks. We implemented and tested our algorithm on a large baseline dataset, and also on a set of image feeds from actual cameras already installed in parking lots. We have developed a fully functional system, from server-side image analysis to front-end user interface, to demonstrate the practicality of our method.
no_new_dataset
0.948346
1606.09370
Sunil Sahu
Sunil Kumar Sahu, Ashish Anand, Krishnadev Oruganty, Mahanandeeshwar Gattu
Relation extraction from clinical texts using domain invariant convolutional neural network
This paper has been accepted in ACL BioNLP 2016 Workshop
null
null
null
cs.CL
http://creativecommons.org/publicdomain/zero/1.0/
In recent years extracting relevant information from biomedical and clinical texts such as research articles, discharge summaries, or electronic health records have been a subject of many research efforts and shared challenges. Relation extraction is the process of detecting and classifying the semantic relation among entities in a given piece of texts. Existing models for this task in biomedical domain use either manually engineered features or kernel methods to create feature vector. These features are then fed to classifier for the prediction of the correct class. It turns out that the results of these methods are highly dependent on quality of user designed features and also suffer from curse of dimensionality. In this work we focus on extracting relations from clinical discharge summaries. Our main objective is to exploit the power of convolution neural network (CNN) to learn features automatically and thus reduce the dependency on manual feature engineering. We evaluate performance of the proposed model on i2b2-2010 clinical relation extraction challenge dataset. Our results indicate that convolution neural network can be a good model for relation exaction in clinical text without being dependent on expert's knowledge on defining quality features.
[ { "version": "v1", "created": "Thu, 30 Jun 2016 07:10:07 GMT" } ]
2016-07-01T00:00:00
[ [ "Sahu", "Sunil Kumar", "" ], [ "Anand", "Ashish", "" ], [ "Oruganty", "Krishnadev", "" ], [ "Gattu", "Mahanandeeshwar", "" ] ]
TITLE: Relation extraction from clinical texts using domain invariant convolutional neural network ABSTRACT: In recent years extracting relevant information from biomedical and clinical texts such as research articles, discharge summaries, or electronic health records have been a subject of many research efforts and shared challenges. Relation extraction is the process of detecting and classifying the semantic relation among entities in a given piece of texts. Existing models for this task in biomedical domain use either manually engineered features or kernel methods to create feature vector. These features are then fed to classifier for the prediction of the correct class. It turns out that the results of these methods are highly dependent on quality of user designed features and also suffer from curse of dimensionality. In this work we focus on extracting relations from clinical discharge summaries. Our main objective is to exploit the power of convolution neural network (CNN) to learn features automatically and thus reduce the dependency on manual feature engineering. We evaluate performance of the proposed model on i2b2-2010 clinical relation extraction challenge dataset. Our results indicate that convolution neural network can be a good model for relation exaction in clinical text without being dependent on expert's knowledge on defining quality features.
no_new_dataset
0.949248
1606.09371
Sunil Sahu
Sunil Kumar Sahu, Ashish Anand
Recurrent neural network models for disease name recognition using domain invariant features
This work has been accepted in ACL-2016 as long paper
null
null
null
cs.CL
http://creativecommons.org/publicdomain/zero/1.0/
Hand-crafted features based on linguistic and domain-knowledge play crucial role in determining the performance of disease name recognition systems. Such methods are further limited by the scope of these features or in other words, their ability to cover the contexts or word dependencies within a sentence. In this work, we focus on reducing such dependencies and propose a domain-invariant framework for the disease name recognition task. In particular, we propose various end-to-end recurrent neural network (RNN) models for the tasks of disease name recognition and their classification into four pre-defined categories. We also utilize convolution neural network (CNN) in cascade of RNN to get character-based embedded features and employ it with word-embedded features in our model. We compare our models with the state-of-the-art results for the two tasks on NCBI disease dataset. Our results for the disease mention recognition task indicate that state-of-the-art performance can be obtained without relying on feature engineering. Further the proposed models obtained improved performance on the classification task of disease names.
[ { "version": "v1", "created": "Thu, 30 Jun 2016 07:15:56 GMT" } ]
2016-07-01T00:00:00
[ [ "Sahu", "Sunil Kumar", "" ], [ "Anand", "Ashish", "" ] ]
TITLE: Recurrent neural network models for disease name recognition using domain invariant features ABSTRACT: Hand-crafted features based on linguistic and domain-knowledge play crucial role in determining the performance of disease name recognition systems. Such methods are further limited by the scope of these features or in other words, their ability to cover the contexts or word dependencies within a sentence. In this work, we focus on reducing such dependencies and propose a domain-invariant framework for the disease name recognition task. In particular, we propose various end-to-end recurrent neural network (RNN) models for the tasks of disease name recognition and their classification into four pre-defined categories. We also utilize convolution neural network (CNN) in cascade of RNN to get character-based embedded features and employ it with word-embedded features in our model. We compare our models with the state-of-the-art results for the two tasks on NCBI disease dataset. Our results for the disease mention recognition task indicate that state-of-the-art performance can be obtained without relying on feature engineering. Further the proposed models obtained improved performance on the classification task of disease names.
no_new_dataset
0.947914
1509.04771
Moo K. Chung
Moo K. Chung, Victoria Vilalta-Gil, Paul J. Rathouz, Benjamin B. Lahey, David H. Zald
Mapping Heritability of Large-Scale Brain Networks with a Billion Connections {\em via} Persistent Homology
null
null
null
null
cs.AI q-bio.NC stat.ML
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
In many human brain network studies, we do not have sufficient number (n) of images relative to the number (p) of voxels due to the prohibitively expensive cost of scanning enough subjects. Thus, brain network models usually suffer the small-n large-p problem. Such a problem is often remedied by sparse network models, which are usually solved numerically by optimizing L1-penalties. Unfortunately, due to the computational bottleneck associated with optimizing L1-penalties, it is not practical to apply such methods to construct large-scale brain networks at the voxel-level. In this paper, we propose a new scalable sparse network model using cross-correlations that bypass the computational bottleneck. Our model can build sparse brain networks at the voxel level with p > 25000. Instead of using a single sparse parameter that may not be optimal in other studies and datasets, the computational speed gain enables us to analyze the collection of networks at every possible sparse parameter in a coherent mathematical framework via persistent homology. The method is subsequently applied in determining the extent of heritability on a functional brain network at the voxel-level for the first time using twin fMRI.
[ { "version": "v1", "created": "Tue, 15 Sep 2015 23:54:12 GMT" }, { "version": "v2", "created": "Wed, 29 Jun 2016 13:28:31 GMT" } ]
2016-06-30T00:00:00
[ [ "Chung", "Moo K.", "" ], [ "Vilalta-Gil", "Victoria", "" ], [ "Rathouz", "Paul J.", "" ], [ "Lahey", "Benjamin B.", "" ], [ "Zald", "David H.", "" ] ]
TITLE: Mapping Heritability of Large-Scale Brain Networks with a Billion Connections {\em via} Persistent Homology ABSTRACT: In many human brain network studies, we do not have sufficient number (n) of images relative to the number (p) of voxels due to the prohibitively expensive cost of scanning enough subjects. Thus, brain network models usually suffer the small-n large-p problem. Such a problem is often remedied by sparse network models, which are usually solved numerically by optimizing L1-penalties. Unfortunately, due to the computational bottleneck associated with optimizing L1-penalties, it is not practical to apply such methods to construct large-scale brain networks at the voxel-level. In this paper, we propose a new scalable sparse network model using cross-correlations that bypass the computational bottleneck. Our model can build sparse brain networks at the voxel level with p > 25000. Instead of using a single sparse parameter that may not be optimal in other studies and datasets, the computational speed gain enables us to analyze the collection of networks at every possible sparse parameter in a coherent mathematical framework via persistent homology. The method is subsequently applied in determining the extent of heritability on a functional brain network at the voxel-level for the first time using twin fMRI.
no_new_dataset
0.952882
1511.07067
Satwik Kottur
Satwik Kottur, Ramakrishna Vedantam, Jos\'e M. F. Moura, Devi Parikh
Visual Word2Vec (vis-w2v): Learning Visually Grounded Word Embeddings Using Abstract Scenes
15 pages, 11 figures
null
null
null
cs.CV cs.CL
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We propose a model to learn visually grounded word embeddings (vis-w2v) to capture visual notions of semantic relatedness. While word embeddings trained using text have been extremely successful, they cannot uncover notions of semantic relatedness implicit in our visual world. For instance, although "eats" and "stares at" seem unrelated in text, they share semantics visually. When people are eating something, they also tend to stare at the food. Grounding diverse relations like "eats" and "stares at" into vision remains challenging, despite recent progress in vision. We note that the visual grounding of words depends on semantics, and not the literal pixels. We thus use abstract scenes created from clipart to provide the visual grounding. We find that the embeddings we learn capture fine-grained, visually grounded notions of semantic relatedness. We show improvements over text-only word embeddings (word2vec) on three tasks: common-sense assertion classification, visual paraphrasing and text-based image retrieval. Our code and datasets are available online.
[ { "version": "v1", "created": "Sun, 22 Nov 2015 20:46:42 GMT" }, { "version": "v2", "created": "Wed, 29 Jun 2016 18:15:25 GMT" } ]
2016-06-30T00:00:00
[ [ "Kottur", "Satwik", "" ], [ "Vedantam", "Ramakrishna", "" ], [ "Moura", "José M. F.", "" ], [ "Parikh", "Devi", "" ] ]
TITLE: Visual Word2Vec (vis-w2v): Learning Visually Grounded Word Embeddings Using Abstract Scenes ABSTRACT: We propose a model to learn visually grounded word embeddings (vis-w2v) to capture visual notions of semantic relatedness. While word embeddings trained using text have been extremely successful, they cannot uncover notions of semantic relatedness implicit in our visual world. For instance, although "eats" and "stares at" seem unrelated in text, they share semantics visually. When people are eating something, they also tend to stare at the food. Grounding diverse relations like "eats" and "stares at" into vision remains challenging, despite recent progress in vision. We note that the visual grounding of words depends on semantics, and not the literal pixels. We thus use abstract scenes created from clipart to provide the visual grounding. We find that the embeddings we learn capture fine-grained, visually grounded notions of semantic relatedness. We show improvements over text-only word embeddings (word2vec) on three tasks: common-sense assertion classification, visual paraphrasing and text-based image retrieval. Our code and datasets are available online.
no_new_dataset
0.946498
1606.08805
Mario Valerio Giuffrida
Mario Valerio Giuffrida and Sotirios A. Tsaftaris
Theta-RBM: Unfactored Gated Restricted Boltzmann Machine for Rotation-Invariant Representations
9 pages, 2 figures, 3 tables
null
null
null
cs.CV
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Learning invariant representations is a critical task in computer vision. In this paper, we propose the Theta-Restricted Boltzmann Machine ({\theta}-RBM in short), which builds upon the original RBM formulation and injects the notion of rotation-invariance during the learning procedure. In contrast to previous approaches, we do not transform the training set with all possible rotations. Instead, we rotate the gradient filters when they are computed during the Contrastive Divergence algorithm. We formulate our model as an unfactored gated Boltzmann machine, where another input layer is used to modulate the input visible layer to drive the optimisation procedure. Among our contributions is a mathematical proof that demonstrates that {\theta}-RBM is able to learn rotation-invariant features according to a recently proposed invariance measure. Our method reaches an invariance score of ~90% on mnist-rot dataset, which is the highest result compared with the baseline methods and the current state of the art in transformation-invariant feature learning in RBM. Using an SVM classifier, we also showed that our network learns discriminative features as well, obtaining ~10% of testing error.
[ { "version": "v1", "created": "Tue, 28 Jun 2016 18:02:32 GMT" }, { "version": "v2", "created": "Wed, 29 Jun 2016 09:57:08 GMT" } ]
2016-06-30T00:00:00
[ [ "Giuffrida", "Mario Valerio", "" ], [ "Tsaftaris", "Sotirios A.", "" ] ]
TITLE: Theta-RBM: Unfactored Gated Restricted Boltzmann Machine for Rotation-Invariant Representations ABSTRACT: Learning invariant representations is a critical task in computer vision. In this paper, we propose the Theta-Restricted Boltzmann Machine ({\theta}-RBM in short), which builds upon the original RBM formulation and injects the notion of rotation-invariance during the learning procedure. In contrast to previous approaches, we do not transform the training set with all possible rotations. Instead, we rotate the gradient filters when they are computed during the Contrastive Divergence algorithm. We formulate our model as an unfactored gated Boltzmann machine, where another input layer is used to modulate the input visible layer to drive the optimisation procedure. Among our contributions is a mathematical proof that demonstrates that {\theta}-RBM is able to learn rotation-invariant features according to a recently proposed invariance measure. Our method reaches an invariance score of ~90% on mnist-rot dataset, which is the highest result compared with the baseline methods and the current state of the art in transformation-invariant feature learning in RBM. Using an SVM classifier, we also showed that our network learns discriminative features as well, obtaining ~10% of testing error.
no_new_dataset
0.953665
1606.08927
Huiyuan Zhang
Huiyuan Zhang, Dung T. Nguyen, Soham Das, Huiling Zhang and My T. Thai
Least Cost Influence Maximization Across Multiple Social Networks
21 pages, published in IEEE/ACM Transactions on Networking
IEEE/ACM Transactions on Networking, 24(2), 929-939, March 12, 2015
10.1109/TNET.2015.2394793
null
cs.SI physics.soc-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Recently in Online Social Networks (OSNs), the Least Cost Influence (LCI) problem has become one of the central research topics. It aims at identifying a minimum number of seed users who can trigger a wide cascade of information propagation. Most of existing literature investigated the LCI problem only based on an individual network. However, nowadays users often join several OSNs such that information could be spread across different networks simultaneously. Therefore, in order to obtain the best set of seed users, it is crucial to consider the role of overlapping users under this circumstances. In this article, we propose a unified framework to represent and analyze the influence diffusion in multiplex networks. More specifically, we tackle the LCI problem by mapping a set of networks into a single one via lossless and lossy coupling schemes. The lossless coupling scheme preserves all properties of original networks to achieve high quality solutions, while the lossy coupling scheme offers an attractive alternative when the running time and memory consumption are of primary concern. Various experiments conducted on both real and synthesized datasets have validated the effectiveness of the coupling schemes, which also provide some interesting insights into the process of influence propagation in multiplex networks.
[ { "version": "v1", "created": "Wed, 29 Jun 2016 01:04:29 GMT" } ]
2016-06-30T00:00:00
[ [ "Zhang", "Huiyuan", "" ], [ "Nguyen", "Dung T.", "" ], [ "Das", "Soham", "" ], [ "Zhang", "Huiling", "" ], [ "Thai", "My T.", "" ] ]
TITLE: Least Cost Influence Maximization Across Multiple Social Networks ABSTRACT: Recently in Online Social Networks (OSNs), the Least Cost Influence (LCI) problem has become one of the central research topics. It aims at identifying a minimum number of seed users who can trigger a wide cascade of information propagation. Most of existing literature investigated the LCI problem only based on an individual network. However, nowadays users often join several OSNs such that information could be spread across different networks simultaneously. Therefore, in order to obtain the best set of seed users, it is crucial to consider the role of overlapping users under this circumstances. In this article, we propose a unified framework to represent and analyze the influence diffusion in multiplex networks. More specifically, we tackle the LCI problem by mapping a set of networks into a single one via lossless and lossy coupling schemes. The lossless coupling scheme preserves all properties of original networks to achieve high quality solutions, while the lossy coupling scheme offers an attractive alternative when the running time and memory consumption are of primary concern. Various experiments conducted on both real and synthesized datasets have validated the effectiveness of the coupling schemes, which also provide some interesting insights into the process of influence propagation in multiplex networks.
no_new_dataset
0.948917
1606.08928
Annamalai Narayanan
Annamalai Narayanan, Mahinthan Chandramohan, Lihui Chen, Yang Liu and Santhoshkumar Saminathan
subgraph2vec: Learning Distributed Representations of Rooted Sub-graphs from Large Graphs
null
null
null
null
cs.LG cs.AI cs.CR cs.SE
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
In this paper, we present subgraph2vec, a novel approach for learning latent representations of rooted subgraphs from large graphs inspired by recent advancements in Deep Learning and Graph Kernels. These latent representations encode semantic substructure dependencies in a continuous vector space, which is easily exploited by statistical models for tasks such as graph classification, clustering, link prediction and community detection. subgraph2vec leverages on local information obtained from neighbourhoods of nodes to learn their latent representations in an unsupervised fashion. We demonstrate that subgraph vectors learnt by our approach could be used in conjunction with classifiers such as CNNs, SVMs and relational data clustering algorithms to achieve significantly superior accuracies. Also, we show that the subgraph vectors could be used for building a deep learning variant of Weisfeiler-Lehman graph kernel. Our experiments on several benchmark and large-scale real-world datasets reveal that subgraph2vec achieves significant improvements in accuracies over existing graph kernels on both supervised and unsupervised learning tasks. Specifically, on two realworld program analysis tasks, namely, code clone and malware detection, subgraph2vec outperforms state-of-the-art kernels by more than 17% and 4%, respectively.
[ { "version": "v1", "created": "Wed, 29 Jun 2016 01:05:36 GMT" } ]
2016-06-30T00:00:00
[ [ "Narayanan", "Annamalai", "" ], [ "Chandramohan", "Mahinthan", "" ], [ "Chen", "Lihui", "" ], [ "Liu", "Yang", "" ], [ "Saminathan", "Santhoshkumar", "" ] ]
TITLE: subgraph2vec: Learning Distributed Representations of Rooted Sub-graphs from Large Graphs ABSTRACT: In this paper, we present subgraph2vec, a novel approach for learning latent representations of rooted subgraphs from large graphs inspired by recent advancements in Deep Learning and Graph Kernels. These latent representations encode semantic substructure dependencies in a continuous vector space, which is easily exploited by statistical models for tasks such as graph classification, clustering, link prediction and community detection. subgraph2vec leverages on local information obtained from neighbourhoods of nodes to learn their latent representations in an unsupervised fashion. We demonstrate that subgraph vectors learnt by our approach could be used in conjunction with classifiers such as CNNs, SVMs and relational data clustering algorithms to achieve significantly superior accuracies. Also, we show that the subgraph vectors could be used for building a deep learning variant of Weisfeiler-Lehman graph kernel. Our experiments on several benchmark and large-scale real-world datasets reveal that subgraph2vec achieves significant improvements in accuracies over existing graph kernels on both supervised and unsupervised learning tasks. Specifically, on two realworld program analysis tasks, namely, code clone and malware detection, subgraph2vec outperforms state-of-the-art kernels by more than 17% and 4%, respectively.
no_new_dataset
0.947332
1606.08955
Vinay Bettadapura
Vinay Bettadapura, Caroline Pantofaru, Irfan Essa
Leveraging Contextual Cues for Generating Basketball Highlights
Proceedings of ACM Multimedia 2016
null
null
null
cs.MM
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The massive growth of sports videos has resulted in a need for automatic generation of sports highlights that are comparable in quality to the hand-edited highlights produced by broadcasters such as ESPN. Unlike previous works that mostly use audio-visual cues derived from the video, we propose an approach that additionally leverages contextual cues derived from the environment that the game is being played in. The contextual cues provide information about the excitement levels in the game, which can be ranked and selected to automatically produce high-quality basketball highlights. We introduce a new dataset of 25 NCAA games along with their play-by-play stats and the ground-truth excitement data for each basket. We explore the informativeness of five different cues derived from the video and from the environment through user studies. Our experiments show that for our study participants, the highlights produced by our system are comparable to the ones produced by ESPN for the same games.
[ { "version": "v1", "created": "Wed, 29 Jun 2016 05:04:27 GMT" } ]
2016-06-30T00:00:00
[ [ "Bettadapura", "Vinay", "" ], [ "Pantofaru", "Caroline", "" ], [ "Essa", "Irfan", "" ] ]
TITLE: Leveraging Contextual Cues for Generating Basketball Highlights ABSTRACT: The massive growth of sports videos has resulted in a need for automatic generation of sports highlights that are comparable in quality to the hand-edited highlights produced by broadcasters such as ESPN. Unlike previous works that mostly use audio-visual cues derived from the video, we propose an approach that additionally leverages contextual cues derived from the environment that the game is being played in. The contextual cues provide information about the excitement levels in the game, which can be ranked and selected to automatically produce high-quality basketball highlights. We introduce a new dataset of 25 NCAA games along with their play-by-play stats and the ground-truth excitement data for each basket. We explore the informativeness of five different cues derived from the video and from the environment through user studies. Our experiments show that for our study participants, the highlights produced by our system are comparable to the ones produced by ESPN for the same games.
new_dataset
0.95452
1606.09058
Dimitrios Alikaniotis
Dimitrios Alikaniotis and John N. Williams
A Distributional Semantics Approach to Implicit Language Learning
5 pages, 7 figures, NetWords 2015
null
null
null
cs.CL cs.LG
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
In the present paper we show that distributional information is particularly important when considering concept availability under implicit language learning conditions. Based on results from different behavioural experiments we argue that the implicit learnability of semantic regularities depends on the degree to which the relevant concept is reflected in language use. In our simulations, we train a Vector-Space model on either an English or a Chinese corpus and then feed the resulting representations to a feed-forward neural network. The task of the neural network was to find a mapping between the word representations and the novel words. Using datasets from four behavioural experiments, which used different semantic manipulations, we were able to obtain learning patterns very similar to those obtained by humans.
[ { "version": "v1", "created": "Wed, 29 Jun 2016 12:08:51 GMT" } ]
2016-06-30T00:00:00
[ [ "Alikaniotis", "Dimitrios", "" ], [ "Williams", "John N.", "" ] ]
TITLE: A Distributional Semantics Approach to Implicit Language Learning ABSTRACT: In the present paper we show that distributional information is particularly important when considering concept availability under implicit language learning conditions. Based on results from different behavioural experiments we argue that the implicit learnability of semantic regularities depends on the degree to which the relevant concept is reflected in language use. In our simulations, we train a Vector-Space model on either an English or a Chinese corpus and then feed the resulting representations to a feed-forward neural network. The task of the neural network was to find a mapping between the word representations and the novel words. Using datasets from four behavioural experiments, which used different semantic manipulations, we were able to obtain learning patterns very similar to those obtained by humans.
no_new_dataset
0.950411
1606.09184
Peter Schulam
Peter Schulam and Raman Arora
Disease Trajectory Maps
null
null
null
null
stat.ML cs.LG stat.AP
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Medical researchers are coming to appreciate that many diseases are in fact complex, heterogeneous syndromes composed of subpopulations that express different variants of a related complication. Time series data extracted from individual electronic health records (EHR) offer an exciting new way to study subtle differences in the way these diseases progress over time. In this paper, we focus on answering two questions that can be asked using these databases of time series. First, we want to understand whether there are individuals with similar disease trajectories and whether there are a small number of degrees of freedom that account for differences in trajectories across the population. Second, we want to understand how important clinical outcomes are associated with disease trajectories. To answer these questions, we propose the Disease Trajectory Map (DTM), a novel probabilistic model that learns low-dimensional representations of sparse and irregularly sampled time series. We propose a stochastic variational inference algorithm for learning the DTM that allows the model to scale to large modern medical datasets. To demonstrate the DTM, we analyze data collected on patients with the complex autoimmune disease, scleroderma. We find that DTM learns meaningful representations of disease trajectories and that the representations are significantly associated with important clinical outcomes.
[ { "version": "v1", "created": "Wed, 29 Jun 2016 17:06:45 GMT" } ]
2016-06-30T00:00:00
[ [ "Schulam", "Peter", "" ], [ "Arora", "Raman", "" ] ]
TITLE: Disease Trajectory Maps ABSTRACT: Medical researchers are coming to appreciate that many diseases are in fact complex, heterogeneous syndromes composed of subpopulations that express different variants of a related complication. Time series data extracted from individual electronic health records (EHR) offer an exciting new way to study subtle differences in the way these diseases progress over time. In this paper, we focus on answering two questions that can be asked using these databases of time series. First, we want to understand whether there are individuals with similar disease trajectories and whether there are a small number of degrees of freedom that account for differences in trajectories across the population. Second, we want to understand how important clinical outcomes are associated with disease trajectories. To answer these questions, we propose the Disease Trajectory Map (DTM), a novel probabilistic model that learns low-dimensional representations of sparse and irregularly sampled time series. We propose a stochastic variational inference algorithm for learning the DTM that allows the model to scale to large modern medical datasets. To demonstrate the DTM, we analyze data collected on patients with the complex autoimmune disease, scleroderma. We find that DTM learns meaningful representations of disease trajectories and that the representations are significantly associated with important clinical outcomes.
no_new_dataset
0.947039
1506.05196
Salman Khan Mr.
Salman H. Khan, Munawar Hayat, Mohammed Bennamoun, Roberto Togneri, and Ferdous Sohel
A Discriminative Representation of Convolutional Features for Indoor Scene Recognition
null
null
10.1109/TIP.2016.2567076
null
cs.CV
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Indoor scene recognition is a multi-faceted and challenging problem due to the diverse intra-class variations and the confusing inter-class similarities. This paper presents a novel approach which exploits rich mid-level convolutional features to categorize indoor scenes. Traditionally used convolutional features preserve the global spatial structure, which is a desirable property for general object recognition. However, we argue that this structuredness is not much helpful when we have large variations in scene layouts, e.g., in indoor scenes. We propose to transform the structured convolutional activations to another highly discriminative feature space. The representation in the transformed space not only incorporates the discriminative aspects of the target dataset, but it also encodes the features in terms of the general object categories that are present in indoor scenes. To this end, we introduce a new large-scale dataset of 1300 object categories which are commonly present in indoor scenes. Our proposed approach achieves a significant performance boost over previous state of the art approaches on five major scene classification datasets.
[ { "version": "v1", "created": "Wed, 17 Jun 2015 03:55:19 GMT" } ]
2016-06-29T00:00:00
[ [ "Khan", "Salman H.", "" ], [ "Hayat", "Munawar", "" ], [ "Bennamoun", "Mohammed", "" ], [ "Togneri", "Roberto", "" ], [ "Sohel", "Ferdous", "" ] ]
TITLE: A Discriminative Representation of Convolutional Features for Indoor Scene Recognition ABSTRACT: Indoor scene recognition is a multi-faceted and challenging problem due to the diverse intra-class variations and the confusing inter-class similarities. This paper presents a novel approach which exploits rich mid-level convolutional features to categorize indoor scenes. Traditionally used convolutional features preserve the global spatial structure, which is a desirable property for general object recognition. However, we argue that this structuredness is not much helpful when we have large variations in scene layouts, e.g., in indoor scenes. We propose to transform the structured convolutional activations to another highly discriminative feature space. The representation in the transformed space not only incorporates the discriminative aspects of the target dataset, but it also encodes the features in terms of the general object categories that are present in indoor scenes. To this end, we introduce a new large-scale dataset of 1300 object categories which are commonly present in indoor scenes. Our proposed approach achieves a significant performance boost over previous state of the art approaches on five major scene classification datasets.
new_dataset
0.962638
1506.09215
Simon Lacoste-Julien
Jean-Baptiste Alayrac, Piotr Bojanowski, Nishant Agrawal, Josef Sivic, Ivan Laptev, Simon Lacoste-Julien
Unsupervised Learning from Narrated Instruction Videos
Appears in: 2016 IEEE Conference on Computer Vision and Pattern Recognition (CVPR 2016). 21 pages
null
null
null
cs.CV cs.LG
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We address the problem of automatically learning the main steps to complete a certain task, such as changing a car tire, from a set of narrated instruction videos. The contributions of this paper are three-fold. First, we develop a new unsupervised learning approach that takes advantage of the complementary nature of the input video and the associated narration. The method solves two clustering problems, one in text and one in video, applied one after each other and linked by joint constraints to obtain a single coherent sequence of steps in both modalities. Second, we collect and annotate a new challenging dataset of real-world instruction videos from the Internet. The dataset contains about 800,000 frames for five different tasks that include complex interactions between people and objects, and are captured in a variety of indoor and outdoor settings. Third, we experimentally demonstrate that the proposed method can automatically discover, in an unsupervised manner, the main steps to achieve the task and locate the steps in the input videos.
[ { "version": "v1", "created": "Tue, 30 Jun 2015 19:55:37 GMT" }, { "version": "v2", "created": "Thu, 2 Jul 2015 16:43:36 GMT" }, { "version": "v3", "created": "Mon, 30 Nov 2015 18:10:53 GMT" }, { "version": "v4", "created": "Tue, 28 Jun 2016 18:43:37 GMT" } ]
2016-06-29T00:00:00
[ [ "Alayrac", "Jean-Baptiste", "" ], [ "Bojanowski", "Piotr", "" ], [ "Agrawal", "Nishant", "" ], [ "Sivic", "Josef", "" ], [ "Laptev", "Ivan", "" ], [ "Lacoste-Julien", "Simon", "" ] ]
TITLE: Unsupervised Learning from Narrated Instruction Videos ABSTRACT: We address the problem of automatically learning the main steps to complete a certain task, such as changing a car tire, from a set of narrated instruction videos. The contributions of this paper are three-fold. First, we develop a new unsupervised learning approach that takes advantage of the complementary nature of the input video and the associated narration. The method solves two clustering problems, one in text and one in video, applied one after each other and linked by joint constraints to obtain a single coherent sequence of steps in both modalities. Second, we collect and annotate a new challenging dataset of real-world instruction videos from the Internet. The dataset contains about 800,000 frames for five different tasks that include complex interactions between people and objects, and are captured in a variety of indoor and outdoor settings. Third, we experimentally demonstrate that the proposed method can automatically discover, in an unsupervised manner, the main steps to achieve the task and locate the steps in the input videos.
new_dataset
0.946448
1510.00297
Akshay Gadde
Aamir Anis, Akshay Gadde, Antonio Ortega
Efficient Sampling Set Selection for Bandlimited Graph Signals Using Graph Spectral Proxies
14 pages, 3 figures, 4 tables, Accepted for publication in IEEE Transactions on Signal Processing
null
10.1109/TSP.2016.2546233
null
cs.IT math.IT
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We study the problem of selecting the best sampling set for bandlimited reconstruction of signals on graphs. A frequency domain representation for graph signals can be defined using the eigenvectors and eigenvalues of variation operators that take into account the underlying graph connectivity. Smoothly varying signals defined on the nodes are of particular interest in various applications, and tend to be approximately bandlimited in the frequency basis. Sampling theory for graph signals deals with the problem of choosing the best subset of nodes for reconstructing a bandlimited signal from its samples. Most approaches to this problem require a computation of the frequency basis (i.e., the eigenvectors of the variation operator), followed by a search procedure using the basis elements. This can be impractical, in terms of storage and time complexity, for real datasets involving very large graphs. We circumvent this issue in our formulation by introducing quantities called graph spectral proxies, defined using the powers of the variation operator, in order to approximate the spectral content of graph signals. This allows us to formulate a direct sampling set selection approach that does not require the computation and storage of the basis elements. We show that our approach also provides stable reconstruction when the samples are noisy or when the original signal is only approximately bandlimited. Furthermore, the proposed approach is valid for any choice of the variation operator, thereby covering a wide range of graphs and applications. We demonstrate its effectiveness through various numerical experiments.
[ { "version": "v1", "created": "Thu, 1 Oct 2015 16:14:35 GMT" }, { "version": "v2", "created": "Tue, 8 Mar 2016 01:45:07 GMT" } ]
2016-06-29T00:00:00
[ [ "Anis", "Aamir", "" ], [ "Gadde", "Akshay", "" ], [ "Ortega", "Antonio", "" ] ]
TITLE: Efficient Sampling Set Selection for Bandlimited Graph Signals Using Graph Spectral Proxies ABSTRACT: We study the problem of selecting the best sampling set for bandlimited reconstruction of signals on graphs. A frequency domain representation for graph signals can be defined using the eigenvectors and eigenvalues of variation operators that take into account the underlying graph connectivity. Smoothly varying signals defined on the nodes are of particular interest in various applications, and tend to be approximately bandlimited in the frequency basis. Sampling theory for graph signals deals with the problem of choosing the best subset of nodes for reconstructing a bandlimited signal from its samples. Most approaches to this problem require a computation of the frequency basis (i.e., the eigenvectors of the variation operator), followed by a search procedure using the basis elements. This can be impractical, in terms of storage and time complexity, for real datasets involving very large graphs. We circumvent this issue in our formulation by introducing quantities called graph spectral proxies, defined using the powers of the variation operator, in order to approximate the spectral content of graph signals. This allows us to formulate a direct sampling set selection approach that does not require the computation and storage of the basis elements. We show that our approach also provides stable reconstruction when the samples are noisy or when the original signal is only approximately bandlimited. Furthermore, the proposed approach is valid for any choice of the variation operator, thereby covering a wide range of graphs and applications. We demonstrate its effectiveness through various numerical experiments.
no_new_dataset
0.951774
1603.00546
Jan Egger
Jan Egger, Philip Voglreiter, Mark Dokter, Michael Hofmann, Xiaojun Chen, Wolfram G. Zoller, Dieter Schmalstieg, Alexander Hann
US-Cut: Interactive Algorithm for rapid Detection and Segmentation of Liver Tumors in Ultrasound Acquisitions
6 pages, 6 figures, 1 table, 32 references
SPIE Medical Imaging Conference 2016, Paper 9790-47
10.1117/12.2216509
null
cs.CV cs.CE cs.CG cs.GR
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Ultrasound (US) is the most commonly used liver imaging modality worldwide. It plays an important role in follow-up of cancer patients with liver metastases. We present an interactive segmentation approach for liver tumors in US acquisitions. Due to the low image quality and the low contrast between the tumors and the surrounding tissue in US images, the segmentation is very challenging. Thus, the clinical practice still relies on manual measurement and outlining of the tumors in the US images. We target this problem by applying an interactive segmentation algorithm to the US data, allowing the user to get real-time feedback of the segmentation results. The algorithm has been developed and tested hand-in-hand by physicians and computer scientists to make sure a future practical usage in a clinical setting is feasible. To cover typical acquisitions from the clinical routine, the approach has been evaluated with dozens of datasets where the tumors are hyperechoic (brighter), hypoechoic (darker) or isoechoic (similar) in comparison to the surrounding liver tissue. Due to the interactive real-time behavior of the approach, it was possible even in difficult cases to find satisfying segmentations of the tumors within seconds and without parameter settings, and the average tumor deviation was only 1.4mm compared with manual measurements. However, the long term goal is to ease the volumetric acquisition of liver tumors in order to evaluate for treatment response. Additional aim is the registration of intraoperative US images via the interactive segmentations to the patient's pre-interventional CT acquisitions.
[ { "version": "v1", "created": "Wed, 2 Mar 2016 01:42:48 GMT" } ]
2016-06-29T00:00:00
[ [ "Egger", "Jan", "" ], [ "Voglreiter", "Philip", "" ], [ "Dokter", "Mark", "" ], [ "Hofmann", "Michael", "" ], [ "Chen", "Xiaojun", "" ], [ "Zoller", "Wolfram G.", "" ], [ "Schmalstieg", "Dieter", "" ], [ "Hann", "Alexander", "" ] ]
TITLE: US-Cut: Interactive Algorithm for rapid Detection and Segmentation of Liver Tumors in Ultrasound Acquisitions ABSTRACT: Ultrasound (US) is the most commonly used liver imaging modality worldwide. It plays an important role in follow-up of cancer patients with liver metastases. We present an interactive segmentation approach for liver tumors in US acquisitions. Due to the low image quality and the low contrast between the tumors and the surrounding tissue in US images, the segmentation is very challenging. Thus, the clinical practice still relies on manual measurement and outlining of the tumors in the US images. We target this problem by applying an interactive segmentation algorithm to the US data, allowing the user to get real-time feedback of the segmentation results. The algorithm has been developed and tested hand-in-hand by physicians and computer scientists to make sure a future practical usage in a clinical setting is feasible. To cover typical acquisitions from the clinical routine, the approach has been evaluated with dozens of datasets where the tumors are hyperechoic (brighter), hypoechoic (darker) or isoechoic (similar) in comparison to the surrounding liver tissue. Due to the interactive real-time behavior of the approach, it was possible even in difficult cases to find satisfying segmentations of the tumors within seconds and without parameter settings, and the average tumor deviation was only 1.4mm compared with manual measurements. However, the long term goal is to ease the volumetric acquisition of liver tumors in order to evaluate for treatment response. Additional aim is the registration of intraoperative US images via the interactive segmentations to the patient's pre-interventional CT acquisitions.
no_new_dataset
0.951323
1603.07302
Michelle Fritz
Michelle Fritz, Marivi Fernandez-Serra, Jose M. Soler
Optimization of an exchange-correlation density functional for water
10 pages, 10 figures
null
10.1063/1.4953081
null
physics.chem-ph cond-mat.other physics.comp-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We describe a method, that we call data projection onto parameter space (DPPS), to optimize an energy functional of the electron density, so that it reproduces a dataset of experimental magnitudes. Our scheme, based on Bayes theorem, constrains the optimized functional not to depart unphysically from existing ab initio functionals. The resulting functional maximizes the probability of being the \correct" parametrization of a given functional form, in the sense of Bayes theory. The application of DPPS to water sheds new light on why density functional theory has performed rather poorly for liquid water, on what improvements are needed, and on the intrinsic limitations of the generalized gradient approximation to electron exchange and correlation. Finally, we present tests of our water-optimized functional, that we call vdW-DF-w, showing that it performs very well for a variety of condensed water systems.
[ { "version": "v1", "created": "Wed, 23 Mar 2016 19:02:44 GMT" }, { "version": "v2", "created": "Thu, 24 Mar 2016 11:31:21 GMT" } ]
2016-06-29T00:00:00
[ [ "Fritz", "Michelle", "" ], [ "Fernandez-Serra", "Marivi", "" ], [ "Soler", "Jose M.", "" ] ]
TITLE: Optimization of an exchange-correlation density functional for water ABSTRACT: We describe a method, that we call data projection onto parameter space (DPPS), to optimize an energy functional of the electron density, so that it reproduces a dataset of experimental magnitudes. Our scheme, based on Bayes theorem, constrains the optimized functional not to depart unphysically from existing ab initio functionals. The resulting functional maximizes the probability of being the \correct" parametrization of a given functional form, in the sense of Bayes theory. The application of DPPS to water sheds new light on why density functional theory has performed rather poorly for liquid water, on what improvements are needed, and on the intrinsic limitations of the generalized gradient approximation to electron exchange and correlation. Finally, we present tests of our water-optimized functional, that we call vdW-DF-w, showing that it performs very well for a variety of condensed water systems.
no_new_dataset
0.948106
1606.08495
Mihajlo Grbovic
Erik Ordentlich, Lee Yang, Andy Feng, Peter Cnudde, Mihajlo Grbovic, Nemanja Djuric, Vladan Radosavljevic, Gavin Owens
Network-Efficient Distributed Word2vec Training System for Large Vocabularies
10 pages, 2 figures
null
null
null
cs.CL
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Word2vec is a popular family of algorithms for unsupervised training of dense vector representations of words on large text corpuses. The resulting vectors have been shown to capture semantic relationships among their corresponding words, and have shown promise in reducing a number of natural language processing (NLP) tasks to mathematical operations on these vectors. While heretofore applications of word2vec have centered around vocabularies with a few million words, wherein the vocabulary is the set of words for which vectors are simultaneously trained, novel applications are emerging in areas outside of NLP with vocabularies comprising several 100 million words. Existing word2vec training systems are impractical for training such large vocabularies as they either require that the vectors of all vocabulary words be stored in the memory of a single server or suffer unacceptable training latency due to massive network data transfer. In this paper, we present a novel distributed, parallel training system that enables unprecedented practical training of vectors for vocabularies with several 100 million words on a shared cluster of commodity servers, using far less network traffic than the existing solutions. We evaluate the proposed system on a benchmark dataset, showing that the quality of vectors does not degrade relative to non-distributed training. Finally, for several quarters, the system has been deployed for the purpose of matching queries to ads in Gemini, the sponsored search advertising platform at Yahoo, resulting in significant improvement of business metrics.
[ { "version": "v1", "created": "Mon, 27 Jun 2016 22:00:21 GMT" } ]
2016-06-29T00:00:00
[ [ "Ordentlich", "Erik", "" ], [ "Yang", "Lee", "" ], [ "Feng", "Andy", "" ], [ "Cnudde", "Peter", "" ], [ "Grbovic", "Mihajlo", "" ], [ "Djuric", "Nemanja", "" ], [ "Radosavljevic", "Vladan", "" ], [ "Owens", "Gavin", "" ] ]
TITLE: Network-Efficient Distributed Word2vec Training System for Large Vocabularies ABSTRACT: Word2vec is a popular family of algorithms for unsupervised training of dense vector representations of words on large text corpuses. The resulting vectors have been shown to capture semantic relationships among their corresponding words, and have shown promise in reducing a number of natural language processing (NLP) tasks to mathematical operations on these vectors. While heretofore applications of word2vec have centered around vocabularies with a few million words, wherein the vocabulary is the set of words for which vectors are simultaneously trained, novel applications are emerging in areas outside of NLP with vocabularies comprising several 100 million words. Existing word2vec training systems are impractical for training such large vocabularies as they either require that the vectors of all vocabulary words be stored in the memory of a single server or suffer unacceptable training latency due to massive network data transfer. In this paper, we present a novel distributed, parallel training system that enables unprecedented practical training of vectors for vocabularies with several 100 million words on a shared cluster of commodity servers, using far less network traffic than the existing solutions. We evaluate the proposed system on a benchmark dataset, showing that the quality of vectors does not degrade relative to non-distributed training. Finally, for several quarters, the system has been deployed for the purpose of matching queries to ads in Gemini, the sponsored search advertising platform at Yahoo, resulting in significant improvement of business metrics.
no_new_dataset
0.944995
1606.08534
Ian Wesley-Smith
Ian Wesley-Smith, Carl T. Bergstrom, Jevin D. West
Static Ranking of Scholarly Papers using Article-Level Eigenfactor (ALEF)
null
null
null
null
cs.DL cs.IR
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Microsoft Research hosted the 2016 WSDM Cup Challenge based on the Microsoft Academic Graph. The goal was to provide static rankings for the articles that make up the graph, with the rankings to be evaluated against those of human judges. While the Microsoft Academic Graph provided metadata about many aspects of each scholarly document, we focused more narrowly on citation data and used this contest as an opportunity to test the Article Level Eigenfactor (ALEF), a novel citation-based ranking algorithm, and evaluate its performance against competing algorithms that drew upon multiple facets of the data from a large, real world dataset (122M papers and 757M citations). Our final submission to this contest was scored at 0.676, earning second place.
[ { "version": "v1", "created": "Tue, 28 Jun 2016 01:55:56 GMT" } ]
2016-06-29T00:00:00
[ [ "Wesley-Smith", "Ian", "" ], [ "Bergstrom", "Carl T.", "" ], [ "West", "Jevin D.", "" ] ]
TITLE: Static Ranking of Scholarly Papers using Article-Level Eigenfactor (ALEF) ABSTRACT: Microsoft Research hosted the 2016 WSDM Cup Challenge based on the Microsoft Academic Graph. The goal was to provide static rankings for the articles that make up the graph, with the rankings to be evaluated against those of human judges. While the Microsoft Academic Graph provided metadata about many aspects of each scholarly document, we focused more narrowly on citation data and used this contest as an opportunity to test the Article Level Eigenfactor (ALEF), a novel citation-based ranking algorithm, and evaluate its performance against competing algorithms that drew upon multiple facets of the data from a large, real world dataset (122M papers and 757M citations). Our final submission to this contest was scored at 0.676, earning second place.
no_new_dataset
0.945601
1606.08821
Zhenhao Ge
Zhenhao Ge, Aravind Ganapathiraju, Ananth N. Iyer, Scott A. Randal and Felix I. Wyss
Generation and Pruning of Pronunciation Variants to Improve ASR Accuracy
Interspeech 2016
null
null
null
cs.CL
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Speech recognition, especially name recognition, is widely used in phone services such as company directory dialers, stock quote providers or location finders. It is usually challenging due to pronunciation variations. This paper proposes an efficient and robust data-driven technique which automatically learns acceptable word pronunciations and updates the pronunciation dictionary to build a better lexicon without affecting recognition of other words similar to the target word. It generalizes well on datasets with various sizes, and reduces the error rate on a database with 13000+ human names by 42%, compared to a baseline with regular dictionaries already covering canonical pronunciations of 97%+ words in names, plus a well-trained spelling-to-pronunciation (STP) engine.
[ { "version": "v1", "created": "Tue, 28 Jun 2016 18:44:38 GMT" } ]
2016-06-29T00:00:00
[ [ "Ge", "Zhenhao", "" ], [ "Ganapathiraju", "Aravind", "" ], [ "Iyer", "Ananth N.", "" ], [ "Randal", "Scott A.", "" ], [ "Wyss", "Felix I.", "" ] ]
TITLE: Generation and Pruning of Pronunciation Variants to Improve ASR Accuracy ABSTRACT: Speech recognition, especially name recognition, is widely used in phone services such as company directory dialers, stock quote providers or location finders. It is usually challenging due to pronunciation variations. This paper proposes an efficient and robust data-driven technique which automatically learns acceptable word pronunciations and updates the pronunciation dictionary to build a better lexicon without affecting recognition of other words similar to the target word. It generalizes well on datasets with various sizes, and reduces the error rate on a database with 13000+ human names by 42%, compared to a baseline with regular dictionaries already covering canonical pronunciations of 97%+ words in names, plus a well-trained spelling-to-pronunciation (STP) engine.
no_new_dataset
0.950778
1411.0541
Baharan Mirzasoleiman
Baharan Mirzasoleiman, Amin Karbasi, Rik Sarkar, and Andreas Krause
Distributed Submodular Maximization
null
null
null
null
cs.LG cs.AI cs.DC cs.IR
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Many large-scale machine learning problems--clustering, non-parametric learning, kernel machines, etc.--require selecting a small yet representative subset from a large dataset. Such problems can often be reduced to maximizing a submodular set function subject to various constraints. Classical approaches to submodular optimization require centralized access to the full dataset, which is impractical for truly large-scale problems. In this paper, we consider the problem of submodular function maximization in a distributed fashion. We develop a simple, two-stage protocol GreeDi, that is easily implemented using MapReduce style computations. We theoretically analyze our approach, and show that under certain natural conditions, performance close to the centralized approach can be achieved. We begin with monotone submodular maximization subject to a cardinality constraint, and then extend this approach to obtain approximation guarantees for (not necessarily monotone) submodular maximization subject to more general constraints including matroid or knapsack constraints. In our extensive experiments, we demonstrate the effectiveness of our approach on several applications, including sparse Gaussian process inference and exemplar based clustering on tens of millions of examples using Hadoop.
[ { "version": "v1", "created": "Mon, 3 Nov 2014 16:03:05 GMT" }, { "version": "v2", "created": "Mon, 27 Jun 2016 16:32:35 GMT" } ]
2016-06-28T00:00:00
[ [ "Mirzasoleiman", "Baharan", "" ], [ "Karbasi", "Amin", "" ], [ "Sarkar", "Rik", "" ], [ "Krause", "Andreas", "" ] ]
TITLE: Distributed Submodular Maximization ABSTRACT: Many large-scale machine learning problems--clustering, non-parametric learning, kernel machines, etc.--require selecting a small yet representative subset from a large dataset. Such problems can often be reduced to maximizing a submodular set function subject to various constraints. Classical approaches to submodular optimization require centralized access to the full dataset, which is impractical for truly large-scale problems. In this paper, we consider the problem of submodular function maximization in a distributed fashion. We develop a simple, two-stage protocol GreeDi, that is easily implemented using MapReduce style computations. We theoretically analyze our approach, and show that under certain natural conditions, performance close to the centralized approach can be achieved. We begin with monotone submodular maximization subject to a cardinality constraint, and then extend this approach to obtain approximation guarantees for (not necessarily monotone) submodular maximization subject to more general constraints including matroid or knapsack constraints. In our extensive experiments, we demonstrate the effectiveness of our approach on several applications, including sparse Gaussian process inference and exemplar based clustering on tens of millions of examples using Hadoop.
no_new_dataset
0.9463
1510.08160
Jianan Li
Jianan Li, Xiaodan Liang, ShengMei Shen, Tingfa Xu, Jiashi Feng, Shuicheng Yan
Scale-aware Fast R-CNN for Pedestrian Detection
null
null
null
null
cs.CV
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
In this work, we consider the problem of pedestrian detection in natural scenes. Intuitively, instances of pedestrians with different spatial scales may exhibit dramatically different features. Thus, large variance in instance scales, which results in undesirable large intra-category variance in features, may severely hurt the performance of modern object instance detection methods. We argue that this issue can be substantially alleviated by the divide-and-conquer philosophy. Taking pedestrian detection as an example, we illustrate how we can leverage this philosophy to develop a Scale-Aware Fast R-CNN (SAF R-CNN) framework. The model introduces multiple built-in sub-networks which detect pedestrians with scales from disjoint ranges. Outputs from all the sub-networks are then adaptively combined to generate the final detection results that are shown to be robust to large variance in instance scales, via a gate function defined over the sizes of object proposals. Extensive evaluations on several challenging pedestrian detection datasets well demonstrate the effectiveness of the proposed SAF R-CNN. Particularly, our method achieves state-of-the-art performance on Caltech, INRIA, and ETH, and obtains competitive results on KITTI.
[ { "version": "v1", "created": "Wed, 28 Oct 2015 01:59:14 GMT" }, { "version": "v2", "created": "Mon, 9 Nov 2015 06:08:18 GMT" }, { "version": "v3", "created": "Sat, 25 Jun 2016 09:26:07 GMT" } ]
2016-06-28T00:00:00
[ [ "Li", "Jianan", "" ], [ "Liang", "Xiaodan", "" ], [ "Shen", "ShengMei", "" ], [ "Xu", "Tingfa", "" ], [ "Feng", "Jiashi", "" ], [ "Yan", "Shuicheng", "" ] ]
TITLE: Scale-aware Fast R-CNN for Pedestrian Detection ABSTRACT: In this work, we consider the problem of pedestrian detection in natural scenes. Intuitively, instances of pedestrians with different spatial scales may exhibit dramatically different features. Thus, large variance in instance scales, which results in undesirable large intra-category variance in features, may severely hurt the performance of modern object instance detection methods. We argue that this issue can be substantially alleviated by the divide-and-conquer philosophy. Taking pedestrian detection as an example, we illustrate how we can leverage this philosophy to develop a Scale-Aware Fast R-CNN (SAF R-CNN) framework. The model introduces multiple built-in sub-networks which detect pedestrians with scales from disjoint ranges. Outputs from all the sub-networks are then adaptively combined to generate the final detection results that are shown to be robust to large variance in instance scales, via a gate function defined over the sizes of object proposals. Extensive evaluations on several challenging pedestrian detection datasets well demonstrate the effectiveness of the proposed SAF R-CNN. Particularly, our method achieves state-of-the-art performance on Caltech, INRIA, and ETH, and obtains competitive results on KITTI.
no_new_dataset
0.946646
1604.01792
Tom Sercu
Tom Sercu, Vaibhava Goel
Advances in Very Deep Convolutional Neural Networks for LVCSR
Proc. Interspeech 2016
null
null
null
cs.CL cs.LG cs.NE
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Very deep CNNs with small 3x3 kernels have recently been shown to achieve very strong performance as acoustic models in hybrid NN-HMM speech recognition systems. In this paper we investigate how to efficiently scale these models to larger datasets. Specifically, we address the design choice of pooling and padding along the time dimension which renders convolutional evaluation of sequences highly inefficient. We propose a new CNN design without timepadding and without timepooling, which is slightly suboptimal for accuracy, but has two significant advantages: it enables sequence training and deployment by allowing efficient convolutional evaluation of full utterances, and, it allows for batch normalization to be straightforwardly adopted to CNNs on sequence data. Through batch normalization, we recover the lost peformance from removing the time-pooling, while keeping the benefit of efficient convolutional evaluation. We demonstrate the performance of our models both on larger scale data than before, and after sequence training. Our very deep CNN model sequence trained on the 2000h switchboard dataset obtains 9.4 word error rate on the Hub5 test-set, matching with a single model the performance of the 2015 IBM system combination, which was the previous best published result.
[ { "version": "v1", "created": "Wed, 6 Apr 2016 20:07:52 GMT" }, { "version": "v2", "created": "Sat, 25 Jun 2016 00:27:19 GMT" } ]
2016-06-28T00:00:00
[ [ "Sercu", "Tom", "" ], [ "Goel", "Vaibhava", "" ] ]
TITLE: Advances in Very Deep Convolutional Neural Networks for LVCSR ABSTRACT: Very deep CNNs with small 3x3 kernels have recently been shown to achieve very strong performance as acoustic models in hybrid NN-HMM speech recognition systems. In this paper we investigate how to efficiently scale these models to larger datasets. Specifically, we address the design choice of pooling and padding along the time dimension which renders convolutional evaluation of sequences highly inefficient. We propose a new CNN design without timepadding and without timepooling, which is slightly suboptimal for accuracy, but has two significant advantages: it enables sequence training and deployment by allowing efficient convolutional evaluation of full utterances, and, it allows for batch normalization to be straightforwardly adopted to CNNs on sequence data. Through batch normalization, we recover the lost peformance from removing the time-pooling, while keeping the benefit of efficient convolutional evaluation. We demonstrate the performance of our models both on larger scale data than before, and after sequence training. Our very deep CNN model sequence trained on the 2000h switchboard dataset obtains 9.4 word error rate on the Hub5 test-set, matching with a single model the performance of the 2015 IBM system combination, which was the previous best published result.
no_new_dataset
0.951097
1606.07103
Sai Praneeth Suggu
Sai Praneeth Suggu, Kushwanth N. Goutham, Manoj K. Chinnakotla and Manish Shrivastava
Deep Feature Fusion Network for Answer Quality Prediction in Community Question Answering
Neu-IR '16 SIGIR Workshop on Neural Information Retrieval, July 21, 2016, Pisa, Italy
null
null
null
cs.IR cs.CL
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Community Question Answering (cQA) forums have become a popular medium for soliciting direct answers to specific questions of users from experts or other experienced users on a given topic. However, for a given question, users sometimes have to sift through a large number of low-quality or irrelevant answers to find out the answer which satisfies their information need. To alleviate this, the problem of Answer Quality Prediction (AQP) aims to predict the quality of an answer posted in response to a forum question. Current AQP systems either learn models using - a) various hand-crafted features (HCF) or b) use deep learning (DL) techniques which automatically learn the required feature representations. In this paper, we propose a novel approach for AQP known as - "Deep Feature Fusion Network (DFFN)" which leverages the advantages of both hand-crafted features and deep learning based systems. Given a question-answer pair along with its metadata, DFFN independently - a) learns deep features using a Convolutional Neural Network (CNN) and b) computes hand-crafted features using various external resources and then combines them using a deep neural network trained to predict the final answer quality. DFFN achieves state-of-the-art performance on the standard SemEval-2015 and SemEval-2016 benchmark datasets and outperforms baseline approaches which individually employ either HCF or DL based techniques alone.
[ { "version": "v1", "created": "Wed, 22 Jun 2016 20:58:08 GMT" }, { "version": "v2", "created": "Sun, 26 Jun 2016 05:54:51 GMT" } ]
2016-06-28T00:00:00
[ [ "Suggu", "Sai Praneeth", "" ], [ "Goutham", "Kushwanth N.", "" ], [ "Chinnakotla", "Manoj K.", "" ], [ "Shrivastava", "Manish", "" ] ]
TITLE: Deep Feature Fusion Network for Answer Quality Prediction in Community Question Answering ABSTRACT: Community Question Answering (cQA) forums have become a popular medium for soliciting direct answers to specific questions of users from experts or other experienced users on a given topic. However, for a given question, users sometimes have to sift through a large number of low-quality or irrelevant answers to find out the answer which satisfies their information need. To alleviate this, the problem of Answer Quality Prediction (AQP) aims to predict the quality of an answer posted in response to a forum question. Current AQP systems either learn models using - a) various hand-crafted features (HCF) or b) use deep learning (DL) techniques which automatically learn the required feature representations. In this paper, we propose a novel approach for AQP known as - "Deep Feature Fusion Network (DFFN)" which leverages the advantages of both hand-crafted features and deep learning based systems. Given a question-answer pair along with its metadata, DFFN independently - a) learns deep features using a Convolutional Neural Network (CNN) and b) computes hand-crafted features using various external resources and then combines them using a deep neural network trained to predict the final answer quality. DFFN achieves state-of-the-art performance on the standard SemEval-2015 and SemEval-2016 benchmark datasets and outperforms baseline approaches which individually employ either HCF or DL based techniques alone.
no_new_dataset
0.952397
1606.07285
Wojciech Samek
Farhad Arbabzadah and Gr\'egoire Montavon and Klaus-Robert M\"uller and Wojciech Samek
Identifying individual facial expressions by deconstructing a neural network
12 pages, 7 figures, Paper accepted for GCPR 2016
null
null
null
cs.CV cs.NE stat.ML
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
This paper focuses on the problem of explaining predictions of psychological attributes such as attractiveness, happiness, confidence and intelligence from face photographs using deep neural networks. Since psychological attribute datasets typically suffer from small sample sizes, we apply transfer learning with two base models to avoid overfitting. These models were trained on an age and gender prediction task, respectively. Using a novel explanation method we extract heatmaps that highlight the parts of the image most responsible for the prediction. We further observe that the explanation method provides important insights into the nature of features of the base model, which allow one to assess the aptitude of the base model for a given transfer learning task. Finally, we observe that the multiclass model is more feature rich than its binary counterpart. The experimental evaluation is performed on the 2222 images from the 10k US faces dataset containing psychological attribute labels as well as on a subset of KDEF images.
[ { "version": "v1", "created": "Thu, 23 Jun 2016 12:24:45 GMT" }, { "version": "v2", "created": "Sun, 26 Jun 2016 00:41:35 GMT" } ]
2016-06-28T00:00:00
[ [ "Arbabzadah", "Farhad", "" ], [ "Montavon", "Grégoire", "" ], [ "Müller", "Klaus-Robert", "" ], [ "Samek", "Wojciech", "" ] ]
TITLE: Identifying individual facial expressions by deconstructing a neural network ABSTRACT: This paper focuses on the problem of explaining predictions of psychological attributes such as attractiveness, happiness, confidence and intelligence from face photographs using deep neural networks. Since psychological attribute datasets typically suffer from small sample sizes, we apply transfer learning with two base models to avoid overfitting. These models were trained on an age and gender prediction task, respectively. Using a novel explanation method we extract heatmaps that highlight the parts of the image most responsible for the prediction. We further observe that the explanation method provides important insights into the nature of features of the base model, which allow one to assess the aptitude of the base model for a given transfer learning task. Finally, we observe that the multiclass model is more feature rich than its binary counterpart. The experimental evaluation is performed on the 2222 images from the 10k US faces dataset containing psychological attribute labels as well as on a subset of KDEF images.
no_new_dataset
0.951594
1606.07827
Dan Xie
Dan Xie and Tianmin Shu and Sinisa Todorovic and Song-Chun Zhu
Modeling and Inferring Human Intents and Latent Functional Objects for Trajectory Prediction
null
null
null
null
cs.CV
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
This paper is about detecting functional objects and inferring human intentions in surveillance videos of public spaces. People in the videos are expected to intentionally take shortest paths toward functional objects subject to obstacles, where people can satisfy certain needs (e.g., a vending machine can quench thirst), by following one of three possible intent behaviors: reach a single functional object and stop, or sequentially visit several functional objects, or initially start moving toward one goal but then change the intent to move toward another. Since detecting functional objects in low-resolution surveillance videos is typically unreliable, we call them "dark matter" characterized by the functionality to attract people. We formulate the Agent-based Lagrangian Mechanics wherein human trajectories are probabilistically modeled as motions of agents in many layers of "dark-energy" fields, where each agent can select a particular force field to affect its motions, and thus define the minimum-energy Dijkstra path toward the corresponding source "dark matter". For evaluation, we compiled and annotated a new dataset. The results demonstrate our effectiveness in predicting human intent behaviors and trajectories, and localizing functional objects, as well as discovering distinct functional classes of objects by clustering human motion behavior in the vicinity of functional objects.
[ { "version": "v1", "created": "Fri, 24 Jun 2016 20:15:12 GMT" } ]
2016-06-28T00:00:00
[ [ "Xie", "Dan", "" ], [ "Shu", "Tianmin", "" ], [ "Todorovic", "Sinisa", "" ], [ "Zhu", "Song-Chun", "" ] ]
TITLE: Modeling and Inferring Human Intents and Latent Functional Objects for Trajectory Prediction ABSTRACT: This paper is about detecting functional objects and inferring human intentions in surveillance videos of public spaces. People in the videos are expected to intentionally take shortest paths toward functional objects subject to obstacles, where people can satisfy certain needs (e.g., a vending machine can quench thirst), by following one of three possible intent behaviors: reach a single functional object and stop, or sequentially visit several functional objects, or initially start moving toward one goal but then change the intent to move toward another. Since detecting functional objects in low-resolution surveillance videos is typically unreliable, we call them "dark matter" characterized by the functionality to attract people. We formulate the Agent-based Lagrangian Mechanics wherein human trajectories are probabilistically modeled as motions of agents in many layers of "dark-energy" fields, where each agent can select a particular force field to affect its motions, and thus define the minimum-energy Dijkstra path toward the corresponding source "dark matter". For evaluation, we compiled and annotated a new dataset. The results demonstrate our effectiveness in predicting human intent behaviors and trajectories, and localizing functional objects, as well as discovering distinct functional classes of objects by clustering human motion behavior in the vicinity of functional objects.
new_dataset
0.950915
1606.07869
Dwaipayan Roy
Dwaipayan Roy, Debasis Ganguly, Mandar Mitra, Gareth J.F. Jones
Representing Documents and Queries as Sets of Word Embedded Vectors for Information Retrieval
Neu-IR '16 SIGIR Workshop on Neural Information Retrieval July 21, 2016, Pisa, Italy
null
null
null
cs.IR
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
A major difficulty in applying word vector embeddings in IR is in devising an effective and efficient strategy for obtaining representations of compound units of text, such as whole documents, (in comparison to the atomic words), for the purpose of indexing and scoring documents. Instead of striving for a suitable method for obtaining a single vector representation of a large document of text, we rather aim for developing a similarity metric that makes use of the similarities between the individual embedded word vectors in a document and a query. More specifically, we represent a document and a query as sets of word vectors, and use a standard notion of similarity measure between these sets, computed as a function of the similarities between each constituent word pair from these sets. We then make use of this similarity measure in combination with standard IR based similarities for document ranking. The results of our initial experimental investigations shows that our proposed method improves MAP by up to $5.77\%$, in comparison to standard text-based language model similarity, on the TREC ad-hoc dataset.
[ { "version": "v1", "created": "Sat, 25 Jun 2016 04:35:47 GMT" } ]
2016-06-28T00:00:00
[ [ "Roy", "Dwaipayan", "" ], [ "Ganguly", "Debasis", "" ], [ "Mitra", "Mandar", "" ], [ "Jones", "Gareth J. F.", "" ] ]
TITLE: Representing Documents and Queries as Sets of Word Embedded Vectors for Information Retrieval ABSTRACT: A major difficulty in applying word vector embeddings in IR is in devising an effective and efficient strategy for obtaining representations of compound units of text, such as whole documents, (in comparison to the atomic words), for the purpose of indexing and scoring documents. Instead of striving for a suitable method for obtaining a single vector representation of a large document of text, we rather aim for developing a similarity metric that makes use of the similarities between the individual embedded word vectors in a document and a query. More specifically, we represent a document and a query as sets of word vectors, and use a standard notion of similarity measure between these sets, computed as a function of the similarities between each constituent word pair from these sets. We then make use of this similarity measure in combination with standard IR based similarities for document ranking. The results of our initial experimental investigations shows that our proposed method improves MAP by up to $5.77\%$, in comparison to standard text-based language model similarity, on the TREC ad-hoc dataset.
no_new_dataset
0.94743
1606.07921
Gonzalo Vaca-Castano
Gonzalo Vaca-Castano
Finding the Topic of a Set of Images
null
null
null
null
cs.CV cs.MM
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
In this paper we introduce the problem of determining the topic that a set of images is describing, where every topic is represented as a set of words. Different from other problems like tag assignment or similar, a) we assume multiple images are used as input instead of single image, b) Input images are typically not visually related, c) Input images are not necessarily semantically close, and d) Output word space is unconstrained. In our proposed solution, visual information of each query image is used to retrieve similar images with text labels (tags) from an image database. We consider a scenario where the tags are very noisy and diverse, given that they were obtained by implicit crowd-sourcing in a database of 1 million images and over seventy seven thousand tags. The words or tags associated to each query are processed jointly in a word selection algorithm using random walks that allows to refine the search topic, rejecting words that are not part of the topic and produce a set of words that fairly describe the topic. Experiments on a dataset of 300 topics, with up to twenty images per topic, show that our algorithm performs better than the proposed baseline for any number of query images. We also present a new Conditional Random Field (CRF) word mapping algorithm that preserves the semantic similarity of the mapped words, increasing the performance of the results over the baseline.
[ { "version": "v1", "created": "Sat, 25 Jun 2016 15:06:27 GMT" } ]
2016-06-28T00:00:00
[ [ "Vaca-Castano", "Gonzalo", "" ] ]
TITLE: Finding the Topic of a Set of Images ABSTRACT: In this paper we introduce the problem of determining the topic that a set of images is describing, where every topic is represented as a set of words. Different from other problems like tag assignment or similar, a) we assume multiple images are used as input instead of single image, b) Input images are typically not visually related, c) Input images are not necessarily semantically close, and d) Output word space is unconstrained. In our proposed solution, visual information of each query image is used to retrieve similar images with text labels (tags) from an image database. We consider a scenario where the tags are very noisy and diverse, given that they were obtained by implicit crowd-sourcing in a database of 1 million images and over seventy seven thousand tags. The words or tags associated to each query are processed jointly in a word selection algorithm using random walks that allows to refine the search topic, rejecting words that are not part of the topic and produce a set of words that fairly describe the topic. Experiments on a dataset of 300 topics, with up to twenty images per topic, show that our algorithm performs better than the proposed baseline for any number of query images. We also present a new Conditional Random Field (CRF) word mapping algorithm that preserves the semantic similarity of the mapped words, increasing the performance of the results over the baseline.
no_new_dataset
0.724139
1606.08003
Guy Edward Toh Emerson
Guy Emerson, Ann Copestake
Functional Distributional Semantics
Published at Representation Learning for NLP workshop at ACL 2016, https://sites.google.com/site/repl4nlp2016/
null
null
null
cs.CL
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Vector space models have become popular in distributional semantics, despite the challenges they face in capturing various semantic phenomena. We propose a novel probabilistic framework which draws on both formal semantics and recent advances in machine learning. In particular, we separate predicates from the entities they refer to, allowing us to perform Bayesian inference based on logical forms. We describe an implementation of this framework using a combination of Restricted Boltzmann Machines and feedforward neural networks. Finally, we demonstrate the feasibility of this approach by training it on a parsed corpus and evaluating it on established similarity datasets.
[ { "version": "v1", "created": "Sun, 26 Jun 2016 07:44:08 GMT" } ]
2016-06-28T00:00:00
[ [ "Emerson", "Guy", "" ], [ "Copestake", "Ann", "" ] ]
TITLE: Functional Distributional Semantics ABSTRACT: Vector space models have become popular in distributional semantics, despite the challenges they face in capturing various semantic phenomena. We propose a novel probabilistic framework which draws on both formal semantics and recent advances in machine learning. In particular, we separate predicates from the entities they refer to, allowing us to perform Bayesian inference based on logical forms. We describe an implementation of this framework using a combination of Restricted Boltzmann Machines and feedforward neural networks. Finally, we demonstrate the feasibility of this approach by training it on a parsed corpus and evaluating it on established similarity datasets.
no_new_dataset
0.94625
1606.08057
Lawrence Jackel
Artem Provodin, Liila Torabi, Beat Flepp, Yann LeCun, Michael Sergio, L. D. Jackel, Urs Muller, Jure Zbontar
Fast Incremental Learning for Off-Road Robot Navigation
null
null
null
null
cs.RO
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
A promising approach to autonomous driving is machine learning. In such systems, training datasets are created that capture the sensory input to a vehicle as well as the desired response. A disadvantage of using a learned navigation system is that the learning process itself may require a huge number of training examples and a large amount of computing. To avoid the need to collect a large training set of driving examples, we describe a system that takes advantage of the huge number of training examples provided by ImageNet, but is able to adapt quickly using a small training set for the specific driving environment.
[ { "version": "v1", "created": "Sun, 26 Jun 2016 17:31:02 GMT" } ]
2016-06-28T00:00:00
[ [ "Provodin", "Artem", "" ], [ "Torabi", "Liila", "" ], [ "Flepp", "Beat", "" ], [ "LeCun", "Yann", "" ], [ "Sergio", "Michael", "" ], [ "Jackel", "L. D.", "" ], [ "Muller", "Urs", "" ], [ "Zbontar", "Jure", "" ] ]
TITLE: Fast Incremental Learning for Off-Road Robot Navigation ABSTRACT: A promising approach to autonomous driving is machine learning. In such systems, training datasets are created that capture the sensory input to a vehicle as well as the desired response. A disadvantage of using a learned navigation system is that the learning process itself may require a huge number of training examples and a large amount of computing. To avoid the need to collect a large training set of driving examples, we describe a system that takes advantage of the huge number of training examples provided by ImageNet, but is able to adapt quickly using a small training set for the specific driving environment.
no_new_dataset
0.927034
1606.08132
Iva Bojic
Iva Bojic, Alexander Belyi, Carlo Ratti, Stanislav Sobolevsky
Scaling of foreign attractiveness for countries and states
null
null
null
null
cs.SI physics.soc-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
People's behavior on online social networks, which store geo-tagged information showing where people were or are at the moment, can provide information about their offline life as well. In this paper we present one possible research direction that can be taken using Flickr dataset of publicly available geo-tagged media objects (e.g., photographs, videos). Namely, our focus is on investigating attractiveness of countries or smaller large-scale composite regions (e.g., US states) for foreign visitors where attractiveness is defined as the absolute number of media objects taken in a certain state or country by its foreign visitors compared to its population size. We also consider it together with attractiveness of the destination for the international migration, measured through publicly available dataset provided by United Nations. By having those two datasets, we are able to look at attractiveness from two different perspectives: short-term and long-term one. As our previous study showed that city attractiveness for Spanish cities follows a superlinear trend, here we want to see if the same law is also applicable to country/state (i.e., composite regions) attractiveness. Finally, we provide one possible explanation for the obtained results.
[ { "version": "v1", "created": "Mon, 27 Jun 2016 05:54:30 GMT" } ]
2016-06-28T00:00:00
[ [ "Bojic", "Iva", "" ], [ "Belyi", "Alexander", "" ], [ "Ratti", "Carlo", "" ], [ "Sobolevsky", "Stanislav", "" ] ]
TITLE: Scaling of foreign attractiveness for countries and states ABSTRACT: People's behavior on online social networks, which store geo-tagged information showing where people were or are at the moment, can provide information about their offline life as well. In this paper we present one possible research direction that can be taken using Flickr dataset of publicly available geo-tagged media objects (e.g., photographs, videos). Namely, our focus is on investigating attractiveness of countries or smaller large-scale composite regions (e.g., US states) for foreign visitors where attractiveness is defined as the absolute number of media objects taken in a certain state or country by its foreign visitors compared to its population size. We also consider it together with attractiveness of the destination for the international migration, measured through publicly available dataset provided by United Nations. By having those two datasets, we are able to look at attractiveness from two different perspectives: short-term and long-term one. As our previous study showed that city attractiveness for Spanish cities follows a superlinear trend, here we want to see if the same law is also applicable to country/state (i.e., composite regions) attractiveness. Finally, we provide one possible explanation for the obtained results.
no_new_dataset
0.937954
1606.08270
Naomi Saphra
Naomi Saphra and Adam Lopez
Evaluating Informal-Domain Word Representations With UrbanDictionary
null
null
null
null
cs.CL
http://creativecommons.org/licenses/by-sa/4.0/
Existing corpora for intrinsic evaluation are not targeted towards tasks in informal domains such as Twitter or news comment forums. We want to test whether a representation of informal words fulfills the promise of eliding explicit text normalization as a preprocessing step. One possible evaluation metric for such domains is the proximity of spelling variants. We propose how such a metric might be computed and how a spelling variant dataset can be collected using UrbanDictionary.
[ { "version": "v1", "created": "Mon, 27 Jun 2016 13:39:54 GMT" } ]
2016-06-28T00:00:00
[ [ "Saphra", "Naomi", "" ], [ "Lopez", "Adam", "" ] ]
TITLE: Evaluating Informal-Domain Word Representations With UrbanDictionary ABSTRACT: Existing corpora for intrinsic evaluation are not targeted towards tasks in informal domains such as Twitter or news comment forums. We want to test whether a representation of informal words fulfills the promise of eliding explicit text normalization as a preprocessing step. One possible evaluation metric for such domains is the proximity of spelling variants. We propose how such a metric might be computed and how a spelling variant dataset can be collected using UrbanDictionary.
new_dataset
0.754259
1601.02306
Iva Bojic
Iva Bojic, Ivana Nizetic-Kosovic, Alexander Belyi, Vedran Podobnik, Stanislav Sobolevsky, Stanislav Sobolevsky, Carlo Ratti
Sublinear scaling of country attractiveness observed from Flickr dataset
null
null
null
null
cs.SI
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The number of people who decide to share their photographs publicly increases every day, consequently making available new almost real-time insights of human behavior while traveling. Rather than having this statistic once a month or yearly, urban planners and touristic workers now can make decisions almost simultaneously with the emergence of new events. Moreover, these datasets can be used not only to compare how popular different touristic places are, but also predict how popular they should be taking into an account their characteristics. In this paper we investigate how country attractiveness scales with its population and size using number of foreign users taking photographs, which is observed from Flickr dataset, as a proxy for attractiveness. The results showed two things: to a certain extent country attractiveness scales with population, but does not with its size; and unlike in case of Spanish cities, country attractiveness scales sublinearly with population, and not superlinearly.
[ { "version": "v1", "created": "Mon, 11 Jan 2016 02:41:20 GMT" } ]
2016-06-27T00:00:00
[ [ "Bojic", "Iva", "" ], [ "Nizetic-Kosovic", "Ivana", "" ], [ "Belyi", "Alexander", "" ], [ "Podobnik", "Vedran", "" ], [ "Sobolevsky", "Stanislav", "" ], [ "Sobolevsky", "Stanislav", "" ], [ "Ratti", "Carlo", "" ] ]
TITLE: Sublinear scaling of country attractiveness observed from Flickr dataset ABSTRACT: The number of people who decide to share their photographs publicly increases every day, consequently making available new almost real-time insights of human behavior while traveling. Rather than having this statistic once a month or yearly, urban planners and touristic workers now can make decisions almost simultaneously with the emergence of new events. Moreover, these datasets can be used not only to compare how popular different touristic places are, but also predict how popular they should be taking into an account their characteristics. In this paper we investigate how country attractiveness scales with its population and size using number of foreign users taking photographs, which is observed from Flickr dataset, as a proxy for attractiveness. The results showed two things: to a certain extent country attractiveness scales with population, but does not with its size; and unlike in case of Spanish cities, country attractiveness scales sublinearly with population, and not superlinearly.
no_new_dataset
0.942718
1602.06468
Yuyu Zhang
Yuyu Zhang, Mohammad Taha Bahadori, Hang Su, Jimeng Sun
FLASH: Fast Bayesian Optimization for Data Analytic Pipelines
21 pages, KDD 2016
null
null
null
cs.LG
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Modern data science relies on data analytic pipelines to organize interdependent computational steps. Such analytic pipelines often involve different algorithms across multiple steps, each with its own hyperparameters. To achieve the best performance, it is often critical to select optimal algorithms and to set appropriate hyperparameters, which requires large computational efforts. Bayesian optimization provides a principled way for searching optimal hyperparameters for a single algorithm. However, many challenges remain in solving pipeline optimization problems with high-dimensional and highly conditional search space. In this work, we propose Fast LineAr SearcH (FLASH), an efficient method for tuning analytic pipelines. FLASH is a two-layer Bayesian optimization framework, which firstly uses a parametric model to select promising algorithms, then computes a nonparametric model to fine-tune hyperparameters of the promising algorithms. FLASH also includes an effective caching algorithm which can further accelerate the search process. Extensive experiments on a number of benchmark datasets have demonstrated that FLASH significantly outperforms previous state-of-the-art methods in both search speed and accuracy. Using 50% of the time budget, FLASH achieves up to 20% improvement on test error rate compared to the baselines. FLASH also yields state-of-the-art performance on a real-world application for healthcare predictive modeling.
[ { "version": "v1", "created": "Sat, 20 Feb 2016 21:56:49 GMT" }, { "version": "v2", "created": "Mon, 13 Jun 2016 02:06:27 GMT" }, { "version": "v3", "created": "Fri, 24 Jun 2016 01:28:23 GMT" } ]
2016-06-27T00:00:00
[ [ "Zhang", "Yuyu", "" ], [ "Bahadori", "Mohammad Taha", "" ], [ "Su", "Hang", "" ], [ "Sun", "Jimeng", "" ] ]
TITLE: FLASH: Fast Bayesian Optimization for Data Analytic Pipelines ABSTRACT: Modern data science relies on data analytic pipelines to organize interdependent computational steps. Such analytic pipelines often involve different algorithms across multiple steps, each with its own hyperparameters. To achieve the best performance, it is often critical to select optimal algorithms and to set appropriate hyperparameters, which requires large computational efforts. Bayesian optimization provides a principled way for searching optimal hyperparameters for a single algorithm. However, many challenges remain in solving pipeline optimization problems with high-dimensional and highly conditional search space. In this work, we propose Fast LineAr SearcH (FLASH), an efficient method for tuning analytic pipelines. FLASH is a two-layer Bayesian optimization framework, which firstly uses a parametric model to select promising algorithms, then computes a nonparametric model to fine-tune hyperparameters of the promising algorithms. FLASH also includes an effective caching algorithm which can further accelerate the search process. Extensive experiments on a number of benchmark datasets have demonstrated that FLASH significantly outperforms previous state-of-the-art methods in both search speed and accuracy. Using 50% of the time budget, FLASH achieves up to 20% improvement on test error rate compared to the baselines. FLASH also yields state-of-the-art performance on a real-world application for healthcare predictive modeling.
no_new_dataset
0.946349
1603.01547
Ondrej Bajgar
Rudolf Kadlec, Martin Schmid, Ondrej Bajgar and Jan Kleindienst
Text Understanding with the Attention Sum Reader Network
Presented at ACL 2016
null
null
null
cs.CL
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Several large cloze-style context-question-answer datasets have been introduced recently: the CNN and Daily Mail news data and the Children's Book Test. Thanks to the size of these datasets, the associated text comprehension task is well suited for deep-learning techniques that currently seem to outperform all alternative approaches. We present a new, simple model that uses attention to directly pick the answer from the context as opposed to computing the answer using a blended representation of words in the document as is usual in similar models. This makes the model particularly suitable for question-answering problems where the answer is a single word from the document. Ensemble of our models sets new state of the art on all evaluated datasets.
[ { "version": "v1", "created": "Fri, 4 Mar 2016 17:32:42 GMT" }, { "version": "v2", "created": "Fri, 24 Jun 2016 13:04:47 GMT" } ]
2016-06-27T00:00:00
[ [ "Kadlec", "Rudolf", "" ], [ "Schmid", "Martin", "" ], [ "Bajgar", "Ondrej", "" ], [ "Kleindienst", "Jan", "" ] ]
TITLE: Text Understanding with the Attention Sum Reader Network ABSTRACT: Several large cloze-style context-question-answer datasets have been introduced recently: the CNN and Daily Mail news data and the Children's Book Test. Thanks to the size of these datasets, the associated text comprehension task is well suited for deep-learning techniques that currently seem to outperform all alternative approaches. We present a new, simple model that uses attention to directly pick the answer from the context as opposed to computing the answer using a blended representation of words in the document as is usual in similar models. This makes the model particularly suitable for question-answering problems where the answer is a single word from the document. Ensemble of our models sets new state of the art on all evaluated datasets.
no_new_dataset
0.935817
1606.07239
Samuel St-Jean
Samuel St-Jean, Pierrick Coup\'e and Maxime Descoteaux
Non Local Spatial and Angular Matching : Enabling higher spatial resolution diffusion MRI datasets through adaptive denoising
Code available : https://github.com/samuelstjean/nlsam Datasets available : https://github.com/samuelstjean/nlsam_data, Medical Image Analysis, 2016
Medical Image Analysis , Volume 32 , 115 - 130, 2016
10.1016/j.media.2016.02.010
null
cs.CV
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Diffusion magnetic resonance imaging datasets suffer from low Signal-to-Noise Ratio, especially at high b-values. Acquiring data at high b-values contains relevant information and is now of great interest for microstructural and connectomics studies. High noise levels bias the measurements due to the non-Gaussian nature of the noise, which in turn can lead to a false and biased estimation of the diffusion parameters. Additionally, the usage of in-plane acceleration techniques during the acquisition leads to a spatially varying noise distribution, which depends on the parallel acceleration method implemented on the scanner. This paper proposes a novel diffusion MRI denoising technique that can be used on all existing data, without adding to the scanning time. We first apply a statistical framework to convert the noise to Gaussian distributed noise, effectively removing the bias. We then introduce a spatially and angular adaptive denoising technique, the Non Local Spatial and Angular Matching (NLSAM) algorithm. Each volume is first decomposed in small 4D overlapping patches to capture the structure of the diffusion data and a dictionary of atoms is learned on those patches. A local sparse decomposition is then found by bounding the reconstruction error with the local noise variance. We compare against three other state-of-the-art denoising methods and show quantitative local and connectivity results on a synthetic phantom and on an in-vivo high resolution dataset. Overall, our method restores perceptual information, removes the noise bias in common diffusion metrics, restores the extracted peaks coherence and improves reproducibility of tractography. Our work paves the way for higher spatial resolution acquisition of diffusion MRI datasets, which could in turn reveal new anatomical details that are not discernible at the spatial resolution currently used by the diffusion MRI community.
[ { "version": "v1", "created": "Thu, 23 Jun 2016 09:28:29 GMT" } ]
2016-06-27T00:00:00
[ [ "St-Jean", "Samuel", "" ], [ "Coupé", "Pierrick", "" ], [ "Descoteaux", "Maxime", "" ] ]
TITLE: Non Local Spatial and Angular Matching : Enabling higher spatial resolution diffusion MRI datasets through adaptive denoising ABSTRACT: Diffusion magnetic resonance imaging datasets suffer from low Signal-to-Noise Ratio, especially at high b-values. Acquiring data at high b-values contains relevant information and is now of great interest for microstructural and connectomics studies. High noise levels bias the measurements due to the non-Gaussian nature of the noise, which in turn can lead to a false and biased estimation of the diffusion parameters. Additionally, the usage of in-plane acceleration techniques during the acquisition leads to a spatially varying noise distribution, which depends on the parallel acceleration method implemented on the scanner. This paper proposes a novel diffusion MRI denoising technique that can be used on all existing data, without adding to the scanning time. We first apply a statistical framework to convert the noise to Gaussian distributed noise, effectively removing the bias. We then introduce a spatially and angular adaptive denoising technique, the Non Local Spatial and Angular Matching (NLSAM) algorithm. Each volume is first decomposed in small 4D overlapping patches to capture the structure of the diffusion data and a dictionary of atoms is learned on those patches. A local sparse decomposition is then found by bounding the reconstruction error with the local noise variance. We compare against three other state-of-the-art denoising methods and show quantitative local and connectivity results on a synthetic phantom and on an in-vivo high resolution dataset. Overall, our method restores perceptual information, removes the noise bias in common diffusion metrics, restores the extracted peaks coherence and improves reproducibility of tractography. Our work paves the way for higher spatial resolution acquisition of diffusion MRI datasets, which could in turn reveal new anatomical details that are not discernible at the spatial resolution currently used by the diffusion MRI community.
no_new_dataset
0.955899
1606.07496
Roberto Camacho Barranco
Roberto Camacho Barranco (1), Laura M. Rodriguez (1), Rebecca Urbina (1), and M. Shahriar Hossain (1) ((1) The University of Texas at El Paso)
Is a Picture Worth Ten Thousand Words in a Review Dataset?
10 pages, 11 figures, "for associated results, see http://http://auto-captioning.herokuapp.com/" "submitted to DLRS 2016 workshop"
null
null
null
cs.CV cs.CL cs.IR cs.LG cs.NE
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
While textual reviews have become prominent in many recommendation-based systems, automated frameworks to provide relevant visual cues against text reviews where pictures are not available is a new form of task confronted by data mining and machine learning researchers. Suggestions of pictures that are relevant to the content of a review could significantly benefit the users by increasing the effectiveness of a review. We propose a deep learning-based framework to automatically: (1) tag the images available in a review dataset, (2) generate a caption for each image that does not have one, and (3) enhance each review by recommending relevant images that might not be uploaded by the corresponding reviewer. We evaluate the proposed framework using the Yelp Challenge Dataset. While a subset of the images in this particular dataset are correctly captioned, the majority of the pictures do not have any associated text. Moreover, there is no mapping between reviews and images. Each image has a corresponding business-tag where the picture was taken, though. The overall data setting and unavailability of crucial pieces required for a mapping make the problem of recommending images for reviews a major challenge. Qualitative and quantitative evaluations indicate that our proposed framework provides high quality enhancements through automatic captioning, tagging, and recommendation for mapping reviews and images.
[ { "version": "v1", "created": "Thu, 23 Jun 2016 22:04:08 GMT" } ]
2016-06-27T00:00:00
[ [ "Barranco", "Roberto Camacho", "", "The University of Texas at El Paso" ], [ "Rodriguez", "Laura M.", "", "The University of Texas at El Paso" ], [ "Urbina", "Rebecca", "", "The University of Texas at El Paso" ], [ "Hossain", "M. Shahriar", "", "The University of Texas at El Paso" ] ]
TITLE: Is a Picture Worth Ten Thousand Words in a Review Dataset? ABSTRACT: While textual reviews have become prominent in many recommendation-based systems, automated frameworks to provide relevant visual cues against text reviews where pictures are not available is a new form of task confronted by data mining and machine learning researchers. Suggestions of pictures that are relevant to the content of a review could significantly benefit the users by increasing the effectiveness of a review. We propose a deep learning-based framework to automatically: (1) tag the images available in a review dataset, (2) generate a caption for each image that does not have one, and (3) enhance each review by recommending relevant images that might not be uploaded by the corresponding reviewer. We evaluate the proposed framework using the Yelp Challenge Dataset. While a subset of the images in this particular dataset are correctly captioned, the majority of the pictures do not have any associated text. Moreover, there is no mapping between reviews and images. Each image has a corresponding business-tag where the picture was taken, though. The overall data setting and unavailability of crucial pieces required for a mapping make the problem of recommending images for reviews a major challenge. Qualitative and quantitative evaluations indicate that our proposed framework provides high quality enhancements through automatic captioning, tagging, and recommendation for mapping reviews and images.
no_new_dataset
0.949153
1606.07550
Rok Sosic
Jure Leskovec and Rok Sosic
SNAP: A General Purpose Network Analysis and Graph Mining Library
null
null
null
null
cs.SI cs.DB physics.soc-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Large networks are becoming a widely used abstraction for studying complex systems in a broad set of disciplines, ranging from social network analysis to molecular biology and neuroscience. Despite an increasing need to analyze and manipulate large networks, only a limited number of tools are available for this task. Here, we describe Stanford Network Analysis Platform (SNAP), a general-purpose, high-performance system that provides easy to use, high-level operations for analysis and manipulation of large networks. We present SNAP functionality, describe its implementational details, and give performance benchmarks. SNAP has been developed for single big-memory machines and it balances the trade-off between maximum performance, compact in-memory graph representation, and the ability to handle dynamic graphs where nodes and edges are being added or removed over time. SNAP can process massive networks with hundreds of millions of nodes and billions of edges. SNAP offers over 140 different graph algorithms that can efficiently manipulate large graphs, calculate structural properties, generate regular and random graphs, and handle attributes and meta-data on nodes and edges. Besides being able to handle large graphs, an additional strength of SNAP is that networks and their attributes are fully dynamic, they can be modified during the computation at low cost. SNAP is provided as an open source library in C++ as well as a module in Python. We also describe the Stanford Large Network Dataset, a set of social and information real-world networks and datasets, which we make publicly available. The collection is a complementary resource to our SNAP software and is widely used for development and benchmarking of graph analytics algorithms.
[ { "version": "v1", "created": "Fri, 24 Jun 2016 03:17:12 GMT" } ]
2016-06-27T00:00:00
[ [ "Leskovec", "Jure", "" ], [ "Sosic", "Rok", "" ] ]
TITLE: SNAP: A General Purpose Network Analysis and Graph Mining Library ABSTRACT: Large networks are becoming a widely used abstraction for studying complex systems in a broad set of disciplines, ranging from social network analysis to molecular biology and neuroscience. Despite an increasing need to analyze and manipulate large networks, only a limited number of tools are available for this task. Here, we describe Stanford Network Analysis Platform (SNAP), a general-purpose, high-performance system that provides easy to use, high-level operations for analysis and manipulation of large networks. We present SNAP functionality, describe its implementational details, and give performance benchmarks. SNAP has been developed for single big-memory machines and it balances the trade-off between maximum performance, compact in-memory graph representation, and the ability to handle dynamic graphs where nodes and edges are being added or removed over time. SNAP can process massive networks with hundreds of millions of nodes and billions of edges. SNAP offers over 140 different graph algorithms that can efficiently manipulate large graphs, calculate structural properties, generate regular and random graphs, and handle attributes and meta-data on nodes and edges. Besides being able to handle large graphs, an additional strength of SNAP is that networks and their attributes are fully dynamic, they can be modified during the computation at low cost. SNAP is provided as an open source library in C++ as well as a module in Python. We also describe the Stanford Large Network Dataset, a set of social and information real-world networks and datasets, which we make publicly available. The collection is a complementary resource to our SNAP software and is widely used for development and benchmarking of graph analytics algorithms.
new_dataset
0.659707
1606.07565
Daniel Cohen
Daniel Cohen, Qingyao Ai, W. Bruce Croft
Adaptability of Neural Networks on Varying Granularity IR Tasks
4 pages, Neu-IR'16 SIGIR Workshop on Neural Information Retrieval, July 21, 2016, Pisa, Italy
null
null
null
cs.IR cs.CL
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Recent work in Information Retrieval (IR) using Deep Learning models has yielded state of the art results on a variety of IR tasks. Deep neural networks (DNN) are capable of learning ideal representations of data during the training process, removing the need for independently extracting features. However, the structures of these DNNs are often tailored to perform on specific datasets. In addition, IR tasks deal with text at varying levels of granularity from single factoids to documents containing thousands of words. In this paper, we examine the role of the granularity on the performance of common state of the art DNN structures in IR.
[ { "version": "v1", "created": "Fri, 24 Jun 2016 04:40:48 GMT" } ]
2016-06-27T00:00:00
[ [ "Cohen", "Daniel", "" ], [ "Ai", "Qingyao", "" ], [ "Croft", "W. Bruce", "" ] ]
TITLE: Adaptability of Neural Networks on Varying Granularity IR Tasks ABSTRACT: Recent work in Information Retrieval (IR) using Deep Learning models has yielded state of the art results on a variety of IR tasks. Deep neural networks (DNN) are capable of learning ideal representations of data during the training process, removing the need for independently extracting features. However, the structures of these DNNs are often tailored to perform on specific datasets. In addition, IR tasks deal with text at varying levels of granularity from single factoids to documents containing thousands of words. In this paper, we examine the role of the granularity on the performance of common state of the art DNN structures in IR.
no_new_dataset
0.953101
1606.07575
Arash Shahriari
Arash Shahriari
Multipartite Ranking-Selection of Low-Dimensional Instances by Supervised Projection to High-Dimensional Space
15 pages, 1 figure, 2 tables, 3 algorithms, 1 appendix
null
null
null
stat.ML cs.CV cs.LG
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Pruning of redundant or irrelevant instances of data is a key to every successful solution for pattern recognition. In this paper, we present a novel ranking-selection framework for low-length but highly correlated instances. Instead of working in the low-dimensional instance space, we learn a supervised projection to high-dimensional space spanned by the number of classes in the dataset under study. Imposing higher distinctions via exposing the notion of labels to the instances, lets to deploy one versus all ranking for each individual classes and selecting quality instances via adaptive thresholding of the overall scores. To prove the efficiency of our paradigm, we employ it for the purpose of texture understanding which is a hard recognition challenge due to high similarity of texture pixels and low dimensionality of their color features. Our experiments show considerable improvements in recognition performance over other local descriptors on several publicly available datasets.
[ { "version": "v1", "created": "Fri, 24 Jun 2016 06:15:45 GMT" } ]
2016-06-27T00:00:00
[ [ "Shahriari", "Arash", "" ] ]
TITLE: Multipartite Ranking-Selection of Low-Dimensional Instances by Supervised Projection to High-Dimensional Space ABSTRACT: Pruning of redundant or irrelevant instances of data is a key to every successful solution for pattern recognition. In this paper, we present a novel ranking-selection framework for low-length but highly correlated instances. Instead of working in the low-dimensional instance space, we learn a supervised projection to high-dimensional space spanned by the number of classes in the dataset under study. Imposing higher distinctions via exposing the notion of labels to the instances, lets to deploy one versus all ranking for each individual classes and selecting quality instances via adaptive thresholding of the overall scores. To prove the efficiency of our paradigm, we employ it for the purpose of texture understanding which is a hard recognition challenge due to high similarity of texture pixels and low dimensionality of their color features. Our experiments show considerable improvements in recognition performance over other local descriptors on several publicly available datasets.
no_new_dataset
0.953966
1606.07783
Ngoc Thang Vu
Ngoc Thang Vu
Sequential Convolutional Neural Networks for Slot Filling in Spoken Language Understanding
Accepted at Interspeech 2016
null
null
null
cs.CL
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We investigate the usage of convolutional neural networks (CNNs) for the slot filling task in spoken language understanding. We propose a novel CNN architecture for sequence labeling which takes into account the previous context words with preserved order information and pays special attention to the current word with its surrounding context. Moreover, it combines the information from the past and the future words for classification. Our proposed CNN architecture outperforms even the previously best ensembling recurrent neural network model and achieves state-of-the-art results with an F1-score of 95.61% on the ATIS benchmark dataset without using any additional linguistic knowledge and resources.
[ { "version": "v1", "created": "Fri, 24 Jun 2016 18:35:56 GMT" } ]
2016-06-27T00:00:00
[ [ "Vu", "Ngoc Thang", "" ] ]
TITLE: Sequential Convolutional Neural Networks for Slot Filling in Spoken Language Understanding ABSTRACT: We investigate the usage of convolutional neural networks (CNNs) for the slot filling task in spoken language understanding. We propose a novel CNN architecture for sequence labeling which takes into account the previous context words with preserved order information and pays special attention to the current word with its surrounding context. Moreover, it combines the information from the past and the future words for classification. Our proposed CNN architecture outperforms even the previously best ensembling recurrent neural network model and achieves state-of-the-art results with an F1-score of 95.61% on the ATIS benchmark dataset without using any additional linguistic knowledge and resources.
no_new_dataset
0.956186
1510.05328
Pedro Tabacof
Pedro Tabacof, Eduardo Valle
Exploring the Space of Adversarial Images
Copyright 2016 IEEE. This manuscript was accepted at the IEEE International Joint Conference on Neural Networks (IJCNN) 2016. We will link the published version as soon as the DOI is available
null
null
null
cs.NE
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Adversarial examples have raised questions regarding the robustness and security of deep neural networks. In this work we formalize the problem of adversarial images given a pretrained classifier, showing that even in the linear case the resulting optimization problem is nonconvex. We generate adversarial images using shallow and deep classifiers on the MNIST and ImageNet datasets. We probe the pixel space of adversarial images using noise of varying intensity and distribution. We bring novel visualizations that showcase the phenomenon and its high variability. We show that adversarial images appear in large regions in the pixel space, but that, for the same task, a shallow classifier seems more robust to adversarial images than a deep convolutional network.
[ { "version": "v1", "created": "Mon, 19 Oct 2015 00:54:37 GMT" }, { "version": "v2", "created": "Sun, 25 Oct 2015 17:40:25 GMT" }, { "version": "v3", "created": "Mon, 23 Nov 2015 01:14:49 GMT" }, { "version": "v4", "created": "Tue, 10 May 2016 22:36:20 GMT" }, { "version": "v5", "created": "Thu, 23 Jun 2016 04:14:32 GMT" } ]
2016-06-24T00:00:00
[ [ "Tabacof", "Pedro", "" ], [ "Valle", "Eduardo", "" ] ]
TITLE: Exploring the Space of Adversarial Images ABSTRACT: Adversarial examples have raised questions regarding the robustness and security of deep neural networks. In this work we formalize the problem of adversarial images given a pretrained classifier, showing that even in the linear case the resulting optimization problem is nonconvex. We generate adversarial images using shallow and deep classifiers on the MNIST and ImageNet datasets. We probe the pixel space of adversarial images using noise of varying intensity and distribution. We bring novel visualizations that showcase the phenomenon and its high variability. We show that adversarial images appear in large regions in the pixel space, but that, for the same task, a shallow classifier seems more robust to adversarial images than a deep convolutional network.
no_new_dataset
0.952309
1604.06433
Jing Wang
Jing Wang, Yu Cheng, Rogerio Schmidt Feris
Walk and Learn: Facial Attribute Representation Learning from Egocentric Video and Contextual Data
Paper accepted by CVPR 2016
null
null
null
cs.CV
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The way people look in terms of facial attributes (ethnicity, hair color, facial hair, etc.) and the clothes or accessories they wear (sunglasses, hat, hoodies, etc.) is highly dependent on geo-location and weather condition, respectively. This work explores, for the first time, the use of this contextual information, as people with wearable cameras walk across different neighborhoods of a city, in order to learn a rich feature representation for facial attribute classification, without the costly manual annotation required by previous methods. By tracking the faces of casual walkers on more than 40 hours of egocentric video, we are able to cover tens of thousands of different identities and automatically extract nearly 5 million pairs of images connected by or from different face tracks, along with their weather and location context, under pose and lighting variations. These image pairs are then fed into a deep network that preserves similarity of images connected by the same track, in order to capture identity-related attribute features, and optimizes for location and weather prediction to capture additional facial attribute features. Finally, the network is fine-tuned with manually annotated samples. We perform an extensive experimental analysis on wearable data and two standard benchmark datasets based on web images (LFWA and CelebA). Our method outperforms by a large margin a network trained from scratch. Moreover, even without using manually annotated identity labels for pre-training as in previous methods, our approach achieves results that are better than the state of the art.
[ { "version": "v1", "created": "Thu, 21 Apr 2016 19:21:55 GMT" }, { "version": "v2", "created": "Wed, 27 Apr 2016 17:07:33 GMT" }, { "version": "v3", "created": "Wed, 22 Jun 2016 20:51:33 GMT" } ]
2016-06-24T00:00:00
[ [ "Wang", "Jing", "" ], [ "Cheng", "Yu", "" ], [ "Feris", "Rogerio Schmidt", "" ] ]
TITLE: Walk and Learn: Facial Attribute Representation Learning from Egocentric Video and Contextual Data ABSTRACT: The way people look in terms of facial attributes (ethnicity, hair color, facial hair, etc.) and the clothes or accessories they wear (sunglasses, hat, hoodies, etc.) is highly dependent on geo-location and weather condition, respectively. This work explores, for the first time, the use of this contextual information, as people with wearable cameras walk across different neighborhoods of a city, in order to learn a rich feature representation for facial attribute classification, without the costly manual annotation required by previous methods. By tracking the faces of casual walkers on more than 40 hours of egocentric video, we are able to cover tens of thousands of different identities and automatically extract nearly 5 million pairs of images connected by or from different face tracks, along with their weather and location context, under pose and lighting variations. These image pairs are then fed into a deep network that preserves similarity of images connected by the same track, in order to capture identity-related attribute features, and optimizes for location and weather prediction to capture additional facial attribute features. Finally, the network is fine-tuned with manually annotated samples. We perform an extensive experimental analysis on wearable data and two standard benchmark datasets based on web images (LFWA and CelebA). Our method outperforms by a large margin a network trained from scratch. Moreover, even without using manually annotated identity labels for pre-training as in previous methods, our approach achieves results that are better than the state of the art.
no_new_dataset
0.943764
1605.04655
Petr Baudi\v{s}
Petr Baudis, Silvestr Stanko and Jan Sedivy
Joint Learning of Sentence Embeddings for Relevance and Entailment
repl4nlp workshop at ACL Berlin 2016
null
null
null
cs.CL cs.LG cs.NE
http://creativecommons.org/licenses/by/4.0/
We consider the problem of Recognizing Textual Entailment within an Information Retrieval context, where we must simultaneously determine the relevancy as well as degree of entailment for individual pieces of evidence to determine a yes/no answer to a binary natural language question. We compare several variants of neural networks for sentence embeddings in a setting of decision-making based on evidence of varying relevance. We propose a basic model to integrate evidence for entailment, show that joint training of the sentence embeddings to model relevance and entailment is feasible even with no explicit per-evidence supervision, and show the importance of evaluating strong baselines. We also demonstrate the benefit of carrying over text comprehension model trained on an unrelated task for our small datasets. Our research is motivated primarily by a new open dataset we introduce, consisting of binary questions and news-based evidence snippets. We also apply the proposed relevance-entailment model on a similar task of ranking multiple-choice test answers, evaluating it on a preliminary dataset of school test questions as well as the standard MCTest dataset, where we improve the neural model state-of-art.
[ { "version": "v1", "created": "Mon, 16 May 2016 05:50:54 GMT" }, { "version": "v2", "created": "Wed, 22 Jun 2016 22:41:26 GMT" } ]
2016-06-24T00:00:00
[ [ "Baudis", "Petr", "" ], [ "Stanko", "Silvestr", "" ], [ "Sedivy", "Jan", "" ] ]
TITLE: Joint Learning of Sentence Embeddings for Relevance and Entailment ABSTRACT: We consider the problem of Recognizing Textual Entailment within an Information Retrieval context, where we must simultaneously determine the relevancy as well as degree of entailment for individual pieces of evidence to determine a yes/no answer to a binary natural language question. We compare several variants of neural networks for sentence embeddings in a setting of decision-making based on evidence of varying relevance. We propose a basic model to integrate evidence for entailment, show that joint training of the sentence embeddings to model relevance and entailment is feasible even with no explicit per-evidence supervision, and show the importance of evaluating strong baselines. We also demonstrate the benefit of carrying over text comprehension model trained on an unrelated task for our small datasets. Our research is motivated primarily by a new open dataset we introduce, consisting of binary questions and news-based evidence snippets. We also apply the proposed relevance-entailment model on a similar task of ranking multiple-choice test answers, evaluating it on a preliminary dataset of school test questions as well as the standard MCTest dataset, where we improve the neural model state-of-art.
new_dataset
0.961642
1606.06368
Fereshte Khani
Fereshte Khani, Martin Rinard, Percy Liang
Unanimous Prediction for 100% Precision with Application to Learning Semantic Mappings
ACL 2016, Removed the duplicate author name of the previous version
null
null
null
cs.LG cs.AI cs.CL
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Can we train a system that, on any new input, either says "don't know" or makes a prediction that is guaranteed to be correct? We answer the question in the affirmative provided our model family is well-specified. Specifically, we introduce the unanimity principle: only predict when all models consistent with the training data predict the same output. We operationalize this principle for semantic parsing, the task of mapping utterances to logical forms. We develop a simple, efficient method that reasons over the infinite set of all consistent models by only checking two of the models. We prove that our method obtains 100% precision even with a modest amount of training data from a possibly adversarial distribution. Empirically, we demonstrate the effectiveness of our approach on the standard GeoQuery dataset.
[ { "version": "v1", "created": "Mon, 20 Jun 2016 23:59:25 GMT" }, { "version": "v2", "created": "Thu, 23 Jun 2016 07:33:01 GMT" } ]
2016-06-24T00:00:00
[ [ "Khani", "Fereshte", "" ], [ "Rinard", "Martin", "" ], [ "Liang", "Percy", "" ] ]
TITLE: Unanimous Prediction for 100% Precision with Application to Learning Semantic Mappings ABSTRACT: Can we train a system that, on any new input, either says "don't know" or makes a prediction that is guaranteed to be correct? We answer the question in the affirmative provided our model family is well-specified. Specifically, we introduce the unanimity principle: only predict when all models consistent with the training data predict the same output. We operationalize this principle for semantic parsing, the task of mapping utterances to logical forms. We develop a simple, efficient method that reasons over the infinite set of all consistent models by only checking two of the models. We prove that our method obtains 100% precision even with a modest amount of training data from a possibly adversarial distribution. Empirically, we demonstrate the effectiveness of our approach on the standard GeoQuery dataset.
no_new_dataset
0.941601
1606.07088
Carlos Kamienski
Rogerio Minhano, Stenio Fernandes, Carlos Kamienski
Revealing Hidden Connections in Recommendation Networks
null
null
null
null
cs.SI physics.soc-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Companies have been increasingly seeking new mechanisms for making their electronic marketing campaigns to become viral, thus obtaining a cascading recommendation effect similar to word-of-mouth. We analysed a dataset of a magazine publisher that uses email as the main marketing strategy and found out that networks emerging from those campaigns form a very sparse graph. We show that online social networks can be effectively used as a means to expand recommendation networks. Starting from a set of users, called seeders, we crawled Google's Orkut and collected about 20 million users and 80 million relationships. Next, we extended the original recommendation network by adding new edges using Orkut relationships that built a much denser network. Therefore, we advocate that online social networks are much more effective than email-based marketing campaigns
[ { "version": "v1", "created": "Wed, 22 Jun 2016 20:16:46 GMT" } ]
2016-06-24T00:00:00
[ [ "Minhano", "Rogerio", "" ], [ "Fernandes", "Stenio", "" ], [ "Kamienski", "Carlos", "" ] ]
TITLE: Revealing Hidden Connections in Recommendation Networks ABSTRACT: Companies have been increasingly seeking new mechanisms for making their electronic marketing campaigns to become viral, thus obtaining a cascading recommendation effect similar to word-of-mouth. We analysed a dataset of a magazine publisher that uses email as the main marketing strategy and found out that networks emerging from those campaigns form a very sparse graph. We show that online social networks can be effectively used as a means to expand recommendation networks. Starting from a set of users, called seeders, we crawled Google's Orkut and collected about 20 million users and 80 million relationships. Next, we extended the original recommendation network by adding new edges using Orkut relationships that built a much denser network. Therefore, we advocate that online social networks are much more effective than email-based marketing campaigns
no_new_dataset
0.93744
1606.07351
Caiing Dong
Cailing Dong and Arvind Agarwal
A Relevant Content Filtering Based Framework For Data Stream Summarization
8 pages, 8 figures
null
null
null
cs.IR
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Social media platforms are a rich source of information these days, however, of all the available information, only a small fraction is of users' interest. To help users catch up with the latest topics of their interests from the large amount of information available in social media, we present a relevant content filtering based framework for data stream summarization. More specifically, given the topic or event of interest, this framework can dynamically discover and filter out relevant information from irrelevant information in the stream of text provided by social media platforms. It then further captures the most representative and up-to-date information to generate a sequential summary or event story line along with the evolution of the topic or event. Our framework does not depend on any labeled data, it instead uses the weak supervision provided by the user, which matches the real scenarios of users searching for information about an ongoing event. We experimented on two real events traced by a Twitter dataset from TREC 2011. The results verified the effectiveness of relevant content filtering and sequential summary generation of the proposed framework. It also shows its robustness of using the most easy-to-obtain weak supervision, i.e., trending topic or hashtag. Thus, this framework can be easily integrated into social media platforms such as Twitter to generate sequential summaries for the events of interest. We also make the manually generated gold-standard sequential summaries of the two test events publicly available for future use in the community.
[ { "version": "v1", "created": "Thu, 23 Jun 2016 15:49:08 GMT" } ]
2016-06-24T00:00:00
[ [ "Dong", "Cailing", "" ], [ "Agarwal", "Arvind", "" ] ]
TITLE: A Relevant Content Filtering Based Framework For Data Stream Summarization ABSTRACT: Social media platforms are a rich source of information these days, however, of all the available information, only a small fraction is of users' interest. To help users catch up with the latest topics of their interests from the large amount of information available in social media, we present a relevant content filtering based framework for data stream summarization. More specifically, given the topic or event of interest, this framework can dynamically discover and filter out relevant information from irrelevant information in the stream of text provided by social media platforms. It then further captures the most representative and up-to-date information to generate a sequential summary or event story line along with the evolution of the topic or event. Our framework does not depend on any labeled data, it instead uses the weak supervision provided by the user, which matches the real scenarios of users searching for information about an ongoing event. We experimented on two real events traced by a Twitter dataset from TREC 2011. The results verified the effectiveness of relevant content filtering and sequential summary generation of the proposed framework. It also shows its robustness of using the most easy-to-obtain weak supervision, i.e., trending topic or hashtag. Thus, this framework can be easily integrated into social media platforms such as Twitter to generate sequential summaries for the events of interest. We also make the manually generated gold-standard sequential summaries of the two test events publicly available for future use in the community.
no_new_dataset
0.951908
1202.4679
Marco van Hulten MSc
Marco van Hulten, Andreas Sterl, Alessandro Tagliabue, Jean-Claude Dutay, Marion Gehlen, Hein J. W. de Baar, Rob Middag
Aluminium in an ocean general circulation model compared with the West Atlantic Geotraces cruises
J. Mar. Syst. (2012), ISSN 0924-7963. 22 pages, 30 figures, on the occasion of the May 2011 GEOTRACES colloquium
J.Mar.Syst. 126 (2013) 3-23
10.1016/j.jmarsys.2012.05.005
null
physics.ao-ph
http://creativecommons.org/licenses/by-nc-sa/3.0/
A model of aluminium has been developed and implemented in an Ocean General Circulation Model (NEMO-PISCES). In the model, aluminium enters the ocean by means of dust deposition. The internal oceanic processes are described by advection, mixing and reversible scavenging. The model has been evaluated against a number of selected high-quality datasets covering much of the world ocean, especially those from the West Atlantic Geotraces cruises of 2010 and 2011. Generally, the model results are in fair agreement with the observations. However, the model does not describe well the vertical distribution of dissolved Al in the North Atlantic Ocean. The model may require changes in the physical forcing and the vertical dependence of the sinking velocity of biogenic silica to account for other discrepancies. To explore the model behaviour, sensitivity experiments have been performed, in which we changed the key parameters of the scavenging process as well as the input of aluminium into the ocean. This resulted in a better understanding of aluminium in the ocean, and it is now clear which parameter has what effect on the dissolved aluminium distribution and which processes might be missing in the model, among which boundary scavenging and biological incorporation of aluminium into diatoms.
[ { "version": "v1", "created": "Tue, 21 Feb 2012 15:49:20 GMT" }, { "version": "v2", "created": "Fri, 18 May 2012 14:57:08 GMT" }, { "version": "v3", "created": "Wed, 26 Sep 2012 13:39:16 GMT" } ]
2016-06-23T00:00:00
[ [ "van Hulten", "Marco", "" ], [ "Sterl", "Andreas", "" ], [ "Tagliabue", "Alessandro", "" ], [ "Dutay", "Jean-Claude", "" ], [ "Gehlen", "Marion", "" ], [ "de Baar", "Hein J. W.", "" ], [ "Middag", "Rob", "" ] ]
TITLE: Aluminium in an ocean general circulation model compared with the West Atlantic Geotraces cruises ABSTRACT: A model of aluminium has been developed and implemented in an Ocean General Circulation Model (NEMO-PISCES). In the model, aluminium enters the ocean by means of dust deposition. The internal oceanic processes are described by advection, mixing and reversible scavenging. The model has been evaluated against a number of selected high-quality datasets covering much of the world ocean, especially those from the West Atlantic Geotraces cruises of 2010 and 2011. Generally, the model results are in fair agreement with the observations. However, the model does not describe well the vertical distribution of dissolved Al in the North Atlantic Ocean. The model may require changes in the physical forcing and the vertical dependence of the sinking velocity of biogenic silica to account for other discrepancies. To explore the model behaviour, sensitivity experiments have been performed, in which we changed the key parameters of the scavenging process as well as the input of aluminium into the ocean. This resulted in a better understanding of aluminium in the ocean, and it is now clear which parameter has what effect on the dissolved aluminium distribution and which processes might be missing in the model, among which boundary scavenging and biological incorporation of aluminium into diatoms.
no_new_dataset
0.946448
1605.02276
Manaal Faruqui
Manaal Faruqui, Yulia Tsvetkov, Pushpendre Rastogi, Chris Dyer
Problems With Evaluation of Word Embeddings Using Word Similarity Tasks
The First Workshop on Evaluating Vector Space Representations for NLP
null
null
null
cs.CL
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Lacking standardized extrinsic evaluation methods for vector representations of words, the NLP community has relied heavily on word similarity tasks as a proxy for intrinsic evaluation of word vectors. Word similarity evaluation, which correlates the distance between vectors and human judgments of semantic similarity is attractive, because it is computationally inexpensive and fast. In this paper we present several problems associated with the evaluation of word vectors on word similarity datasets, and summarize existing solutions. Our study suggests that the use of word similarity tasks for evaluation of word vectors is not sustainable and calls for further research on evaluation methods.
[ { "version": "v1", "created": "Sun, 8 May 2016 05:09:28 GMT" }, { "version": "v2", "created": "Tue, 21 Jun 2016 04:48:34 GMT" }, { "version": "v3", "created": "Wed, 22 Jun 2016 02:41:04 GMT" } ]
2016-06-23T00:00:00
[ [ "Faruqui", "Manaal", "" ], [ "Tsvetkov", "Yulia", "" ], [ "Rastogi", "Pushpendre", "" ], [ "Dyer", "Chris", "" ] ]
TITLE: Problems With Evaluation of Word Embeddings Using Word Similarity Tasks ABSTRACT: Lacking standardized extrinsic evaluation methods for vector representations of words, the NLP community has relied heavily on word similarity tasks as a proxy for intrinsic evaluation of word vectors. Word similarity evaluation, which correlates the distance between vectors and human judgments of semantic similarity is attractive, because it is computationally inexpensive and fast. In this paper we present several problems associated with the evaluation of word vectors on word similarity datasets, and summarize existing solutions. Our study suggests that the use of word similarity tasks for evaluation of word vectors is not sustainable and calls for further research on evaluation methods.
no_new_dataset
0.944022
1606.05409
Linfeng Song
Linfeng Song, Zhiguo Wang, Haitao Mi and Daniel Gildea
Sense Embedding Learning for Word Sense Induction
6 pages, no figures in *SEM 2016
null
null
null
cs.CL
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Conventional word sense induction (WSI) methods usually represent each instance with discrete linguistic features or cooccurrence features, and train a model for each polysemous word individually. In this work, we propose to learn sense embeddings for the WSI task. In the training stage, our method induces several sense centroids (embedding) for each polysemous word. In the testing stage, our method represents each instance as a contextual vector, and induces its sense by finding the nearest sense centroid in the embedding space. The advantages of our method are (1) distributed sense vectors are taken as the knowledge representations which are trained discriminatively, and usually have better performance than traditional count-based distributional models, and (2) a general model for the whole vocabulary is jointly trained to induce sense centroids under the mutlitask learning framework. Evaluated on SemEval-2010 WSI dataset, our method outperforms all participants and most of the recent state-of-the-art methods. We further verify the two advantages by comparing with carefully designed baselines.
[ { "version": "v1", "created": "Fri, 17 Jun 2016 02:49:52 GMT" }, { "version": "v2", "created": "Wed, 22 Jun 2016 04:59:08 GMT" } ]
2016-06-23T00:00:00
[ [ "Song", "Linfeng", "" ], [ "Wang", "Zhiguo", "" ], [ "Mi", "Haitao", "" ], [ "Gildea", "Daniel", "" ] ]
TITLE: Sense Embedding Learning for Word Sense Induction ABSTRACT: Conventional word sense induction (WSI) methods usually represent each instance with discrete linguistic features or cooccurrence features, and train a model for each polysemous word individually. In this work, we propose to learn sense embeddings for the WSI task. In the training stage, our method induces several sense centroids (embedding) for each polysemous word. In the testing stage, our method represents each instance as a contextual vector, and induces its sense by finding the nearest sense centroid in the embedding space. The advantages of our method are (1) distributed sense vectors are taken as the knowledge representations which are trained discriminatively, and usually have better performance than traditional count-based distributional models, and (2) a general model for the whole vocabulary is jointly trained to induce sense centroids under the mutlitask learning framework. Evaluated on SemEval-2010 WSI dataset, our method outperforms all participants and most of the recent state-of-the-art methods. We further verify the two advantages by comparing with carefully designed baselines.
no_new_dataset
0.947527
1606.06769
Kai Zhao
Kai Zhao
Network Analysis of Urban Traffic with Big Bus Data
This technical report won the best hack award in Big Data Science Hackathon, Helsinki,2015
null
null
null
physics.soc-ph cs.SI
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Urban traffic analysis is crucial for traffic forecasting systems, urban planning and, more recently, various mobile and network applications. In this paper, we analyse urban traffic with network and statistical methods. Our analysis is based on one big bus dataset containing 45 million bus arrival samples in Helsinki. We mainly address following questions: 1. How can we identify the areas that cause most of the traffic in the city? 2. Why there is a urban traffic? Is bus traffic a key cause of the urban traffic? 3. How can we improve the urban traffic systems? To answer these questions, first, the betweenness is used to identify the most import areas that cause most traffics. Second, we find that bus traffic is not an important cause of urban traffic using statistical methods. We differentiate the urban traffic and the bus traffic in a city. We use bus delay as an identification of the urban traffic, and the number of bus as an identification of the bus traffic. Third, we give our solutions on how to improve urban traffic by the traffic simulation on road networks. We show that adding more buses during the peak time and providing better bus schedule plan in the hot areas like railway station, metro station, shopping malls etc. will reduce the urban traffic.
[ { "version": "v1", "created": "Tue, 21 Jun 2016 21:04:06 GMT" } ]
2016-06-23T00:00:00
[ [ "Zhao", "Kai", "" ] ]
TITLE: Network Analysis of Urban Traffic with Big Bus Data ABSTRACT: Urban traffic analysis is crucial for traffic forecasting systems, urban planning and, more recently, various mobile and network applications. In this paper, we analyse urban traffic with network and statistical methods. Our analysis is based on one big bus dataset containing 45 million bus arrival samples in Helsinki. We mainly address following questions: 1. How can we identify the areas that cause most of the traffic in the city? 2. Why there is a urban traffic? Is bus traffic a key cause of the urban traffic? 3. How can we improve the urban traffic systems? To answer these questions, first, the betweenness is used to identify the most import areas that cause most traffics. Second, we find that bus traffic is not an important cause of urban traffic using statistical methods. We differentiate the urban traffic and the bus traffic in a city. We use bus delay as an identification of the urban traffic, and the number of bus as an identification of the bus traffic. Third, we give our solutions on how to improve urban traffic by the traffic simulation on road networks. We show that adding more buses during the peak time and providing better bus schedule plan in the hot areas like railway station, metro station, shopping malls etc. will reduce the urban traffic.
no_new_dataset
0.907476
1606.06854
Xingyi Zhou
Xingyi Zhou, Qingfu Wan, Wei Zhang, Xiangyang Xue, Yichen Wei
Model-based Deep Hand Pose Estimation
null
null
null
null
cs.CV
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Previous learning based hand pose estimation methods does not fully exploit the prior information in hand model geometry. Instead, they usually rely a separate model fitting step to generate valid hand poses. Such a post processing is inconvenient and sub-optimal. In this work, we propose a model based deep learning approach that adopts a forward kinematics based layer to ensure the geometric validity of estimated poses. For the first time, we show that embedding such a non-linear generative process in deep learning is feasible for hand pose estimation. Our approach is verified on challenging public datasets and achieves state-of-the-art performance.
[ { "version": "v1", "created": "Wed, 22 Jun 2016 08:47:06 GMT" } ]
2016-06-23T00:00:00
[ [ "Zhou", "Xingyi", "" ], [ "Wan", "Qingfu", "" ], [ "Zhang", "Wei", "" ], [ "Xue", "Xiangyang", "" ], [ "Wei", "Yichen", "" ] ]
TITLE: Model-based Deep Hand Pose Estimation ABSTRACT: Previous learning based hand pose estimation methods does not fully exploit the prior information in hand model geometry. Instead, they usually rely a separate model fitting step to generate valid hand poses. Such a post processing is inconvenient and sub-optimal. In this work, we propose a model based deep learning approach that adopts a forward kinematics based layer to ensure the geometric validity of estimated poses. For the first time, we show that embedding such a non-linear generative process in deep learning is feasible for hand pose estimation. Our approach is verified on challenging public datasets and achieves state-of-the-art performance.
no_new_dataset
0.952086
1606.06975
Yuehaw Khoo
Yuehaw Khoo, Amit Singer, David Cowburn
Bias Correction in Saupe Tensor Estimation
24 pages, 5 figures
null
null
null
cs.CE
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Estimation of the Saupe tensor is central to the determination of molecular structures from residual dipolar couplings (RDC) or chemical shift anisotropies. Assuming a given template structure, the singular value decomposition (SVD) method proposed in Losonczi et al. 1999 has been used traditionally to estimate the Saupe tensor. Despite its simplicity, whenever the template structure has large structural noise, the eigenvalues of the estimated tensor have a magnitude systematically smaller than their actual values. This leads to systematic error when calculating the eigenvalue dependent parameters, magnitude and rhombicity. We propose here a Monte Carlo simulation method to remove such bias. We further demonstrate the effectiveness of our method in the setting when the eigenvalue estimates from multiple template protein fragments are available and their average is used as an improved eigenvalue estimator. For both synthetic and experimental RDC datasets of ubiquitin, when using template fragments corrupted by large noise, the magnitude of our proposed bias-reduced estimator generally reaches at least 90% of the actual value, whereas the magnitude of SVD estimator can be shrunk below 80% of the true value.
[ { "version": "v1", "created": "Wed, 22 Jun 2016 15:05:23 GMT" } ]
2016-06-23T00:00:00
[ [ "Khoo", "Yuehaw", "" ], [ "Singer", "Amit", "" ], [ "Cowburn", "David", "" ] ]
TITLE: Bias Correction in Saupe Tensor Estimation ABSTRACT: Estimation of the Saupe tensor is central to the determination of molecular structures from residual dipolar couplings (RDC) or chemical shift anisotropies. Assuming a given template structure, the singular value decomposition (SVD) method proposed in Losonczi et al. 1999 has been used traditionally to estimate the Saupe tensor. Despite its simplicity, whenever the template structure has large structural noise, the eigenvalues of the estimated tensor have a magnitude systematically smaller than their actual values. This leads to systematic error when calculating the eigenvalue dependent parameters, magnitude and rhombicity. We propose here a Monte Carlo simulation method to remove such bias. We further demonstrate the effectiveness of our method in the setting when the eigenvalue estimates from multiple template protein fragments are available and their average is used as an improved eigenvalue estimator. For both synthetic and experimental RDC datasets of ubiquitin, when using template fragments corrupted by large noise, the magnitude of our proposed bias-reduced estimator generally reaches at least 90% of the actual value, whereas the magnitude of SVD estimator can be shrunk below 80% of the true value.
no_new_dataset
0.948106
1601.00881
Tomoyuki Obuchi
Tomoyuki Obuchi and Yoshiyuki Kabashima
Cross validation in LASSO and its acceleration
32 pages, 7 figures
null
10.1088/1742-5468/2016/05/053304
null
cs.IT cond-mat.dis-nn cond-mat.stat-mech math.IT
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We investigate leave-one-out cross validation (CV) as a determinator of the weight of the penalty term in the least absolute shrinkage and selection operator (LASSO). First, on the basis of the message passing algorithm and a perturbative discussion assuming that the number of observations is sufficiently large, we provide simple formulas for approximately assessing two types of CV errors, which enable us to significantly reduce the necessary cost of computation. These formulas also provide a simple connection of the CV errors to the residual sums of squares between the reconstructed and the given measurements. Second, on the basis of this finding, we analytically evaluate the CV errors when the design matrix is given as a simple random matrix in the large size limit by using the replica method. Finally, these results are compared with those of numerical simulations on finite-size systems and are confirmed to be correct. We also apply the simple formulas of the first type of CV error to an actual dataset of the supernovae.
[ { "version": "v1", "created": "Tue, 29 Dec 2015 02:50:51 GMT" }, { "version": "v2", "created": "Fri, 4 Mar 2016 09:34:44 GMT" } ]
2016-06-22T00:00:00
[ [ "Obuchi", "Tomoyuki", "" ], [ "Kabashima", "Yoshiyuki", "" ] ]
TITLE: Cross validation in LASSO and its acceleration ABSTRACT: We investigate leave-one-out cross validation (CV) as a determinator of the weight of the penalty term in the least absolute shrinkage and selection operator (LASSO). First, on the basis of the message passing algorithm and a perturbative discussion assuming that the number of observations is sufficiently large, we provide simple formulas for approximately assessing two types of CV errors, which enable us to significantly reduce the necessary cost of computation. These formulas also provide a simple connection of the CV errors to the residual sums of squares between the reconstructed and the given measurements. Second, on the basis of this finding, we analytically evaluate the CV errors when the design matrix is given as a simple random matrix in the large size limit by using the replica method. Finally, these results are compared with those of numerical simulations on finite-size systems and are confirmed to be correct. We also apply the simple formulas of the first type of CV error to an actual dataset of the supernovae.
no_new_dataset
0.941223
1601.03055
Yuqing Hou
Yuqing Hou, Zhouchen Lin, Jin-ge Yao
Subspace Clustering Based Tag Sharing for Inductive Tag Matrix Refinement with Complex Errors
4 pages
null
null
null
cs.CV
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Annotating images with tags is useful for indexing and retrieving images. However, many available annotation data include missing or inaccurate annotations. In this paper, we propose an image annotation framework which sequentially performs tag completion and refinement. We utilize the subspace property of data via sparse subspace clustering for tag completion. Then we propose a novel matrix completion model for tag refinement, integrating visual correlation, semantic correlation and the novelly studied property of complex errors. The proposed method outperforms the state-of-the-art approaches on multiple benchmark datasets even when they contain certain levels of annotation noise.
[ { "version": "v1", "created": "Tue, 12 Jan 2016 21:03:43 GMT" }, { "version": "v2", "created": "Tue, 1 Mar 2016 04:41:53 GMT" }, { "version": "v3", "created": "Tue, 21 Jun 2016 15:48:06 GMT" } ]
2016-06-22T00:00:00
[ [ "Hou", "Yuqing", "" ], [ "Lin", "Zhouchen", "" ], [ "Yao", "Jin-ge", "" ] ]
TITLE: Subspace Clustering Based Tag Sharing for Inductive Tag Matrix Refinement with Complex Errors ABSTRACT: Annotating images with tags is useful for indexing and retrieving images. However, many available annotation data include missing or inaccurate annotations. In this paper, we propose an image annotation framework which sequentially performs tag completion and refinement. We utilize the subspace property of data via sparse subspace clustering for tag completion. Then we propose a novel matrix completion model for tag refinement, integrating visual correlation, semantic correlation and the novelly studied property of complex errors. The proposed method outperforms the state-of-the-art approaches on multiple benchmark datasets even when they contain certain levels of annotation noise.
no_new_dataset
0.947914
1602.01237
Shanshan Zhang
Shanshan Zhang, Rodrigo Benenson, Mohamed Omran, Jan Hosang, and Bernt Schiele
How Far are We from Solving Pedestrian Detection?
CVPR16 camera ready
null
null
null
cs.CV
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Encouraged by the recent progress in pedestrian detection, we investigate the gap between current state-of-the-art methods and the "perfect single frame detector". We enable our analysis by creating a human baseline for pedestrian detection (over the Caltech dataset), and by manually clustering the recurrent errors of a top detector. Our results characterize both localization and background-versus-foreground errors. To address localization errors we study the impact of training annotation noise on the detector performance, and show that we can improve even with a small portion of sanitized training data. To address background/foreground discrimination, we study convnets for pedestrian detection, and discuss which factors affect their performance. Other than our in-depth analysis, we report top performance on the Caltech dataset, and provide a new sanitized set of training and test annotations.
[ { "version": "v1", "created": "Wed, 3 Feb 2016 09:45:56 GMT" }, { "version": "v2", "created": "Tue, 21 Jun 2016 11:33:13 GMT" } ]
2016-06-22T00:00:00
[ [ "Zhang", "Shanshan", "" ], [ "Benenson", "Rodrigo", "" ], [ "Omran", "Mohamed", "" ], [ "Hosang", "Jan", "" ], [ "Schiele", "Bernt", "" ] ]
TITLE: How Far are We from Solving Pedestrian Detection? ABSTRACT: Encouraged by the recent progress in pedestrian detection, we investigate the gap between current state-of-the-art methods and the "perfect single frame detector". We enable our analysis by creating a human baseline for pedestrian detection (over the Caltech dataset), and by manually clustering the recurrent errors of a top detector. Our results characterize both localization and background-versus-foreground errors. To address localization errors we study the impact of training annotation noise on the detector performance, and show that we can improve even with a small portion of sanitized training data. To address background/foreground discrimination, we study convnets for pedestrian detection, and discuss which factors affect their performance. Other than our in-depth analysis, we report top performance on the Caltech dataset, and provide a new sanitized set of training and test annotations.
no_new_dataset
0.919859
1602.01827
Yang Zhong
Yang Zhong, Josephine Sullivan, Haibo Li
Leveraging Mid-Level Deep Representations For Predicting Face Attributes in the Wild
In proceedings of 2016 International Conference on Image Processing (ICIP)
null
null
null
cs.CV
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Predicting facial attributes from faces in the wild is very challenging due to pose and lighting variations in the real world. The key to this problem is to build proper feature representations to cope with these unfavourable conditions. Given the success of Convolutional Neural Network (CNN) in image classification, the high-level CNN feature, as an intuitive and reasonable choice, has been widely utilized for this problem. In this paper, however, we consider the mid-level CNN features as an alternative to the high-level ones for attribute prediction. This is based on the observation that face attributes are different: some of them are locally oriented while others are globally defined. Our investigations reveal that the mid-level deep representations outperform the prediction accuracy achieved by the (fine-tuned) high-level abstractions. We empirically demonstrate that the midlevel representations achieve state-of-the-art prediction performance on CelebA and LFWA datasets. Our investigations also show that by utilizing the mid-level representations one can employ a single deep network to achieve both face recognition and attribute prediction.
[ { "version": "v1", "created": "Thu, 4 Feb 2016 20:58:02 GMT" }, { "version": "v2", "created": "Fri, 5 Feb 2016 07:08:05 GMT" }, { "version": "v3", "created": "Tue, 21 Jun 2016 15:52:58 GMT" } ]
2016-06-22T00:00:00
[ [ "Zhong", "Yang", "" ], [ "Sullivan", "Josephine", "" ], [ "Li", "Haibo", "" ] ]
TITLE: Leveraging Mid-Level Deep Representations For Predicting Face Attributes in the Wild ABSTRACT: Predicting facial attributes from faces in the wild is very challenging due to pose and lighting variations in the real world. The key to this problem is to build proper feature representations to cope with these unfavourable conditions. Given the success of Convolutional Neural Network (CNN) in image classification, the high-level CNN feature, as an intuitive and reasonable choice, has been widely utilized for this problem. In this paper, however, we consider the mid-level CNN features as an alternative to the high-level ones for attribute prediction. This is based on the observation that face attributes are different: some of them are locally oriented while others are globally defined. Our investigations reveal that the mid-level deep representations outperform the prediction accuracy achieved by the (fine-tuned) high-level abstractions. We empirically demonstrate that the midlevel representations achieve state-of-the-art prediction performance on CelebA and LFWA datasets. Our investigations also show that by utilizing the mid-level representations one can employ a single deep network to achieve both face recognition and attribute prediction.
no_new_dataset
0.948155
1602.03935
Yang Zhong
Yang Zhong, Josephine Sullivan, Haibo Li
Face Attribute Prediction Using Off-the-Shelf CNN Features
In proceeding of 2016 International Conference on Biometrics (ICB)
null
null
null
cs.CV
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Predicting attributes from face images in the wild is a challenging computer vision problem. To automatically describe face attributes from face containing images, traditionally one needs to cascade three technical blocks --- face localization, facial descriptor construction, and attribute classification --- in a pipeline. As a typical classification problem, face attribute prediction has been addressed using deep learning. Current state-of-the-art performance was achieved by using two cascaded Convolutional Neural Networks (CNNs), which were specifically trained to learn face localization and attribute description. In this paper, we experiment with an alternative way of employing the power of deep representations from CNNs. Combining with conventional face localization techniques, we use off-the-shelf architectures trained for face recognition to build facial descriptors. Recognizing that the describable face attributes are diverse, our face descriptors are constructed from different levels of the CNNs for different attributes to best facilitate face attribute prediction. Experiments on two large datasets, LFWA and CelebA, show that our approach is entirely comparable to the state-of-the-art. Our findings not only demonstrate an efficient face attribute prediction approach, but also raise an important question: how to leverage the power of off-the-shelf CNN representations for novel tasks.
[ { "version": "v1", "created": "Fri, 12 Feb 2016 00:44:16 GMT" }, { "version": "v2", "created": "Tue, 21 Jun 2016 14:27:33 GMT" } ]
2016-06-22T00:00:00
[ [ "Zhong", "Yang", "" ], [ "Sullivan", "Josephine", "" ], [ "Li", "Haibo", "" ] ]
TITLE: Face Attribute Prediction Using Off-the-Shelf CNN Features ABSTRACT: Predicting attributes from face images in the wild is a challenging computer vision problem. To automatically describe face attributes from face containing images, traditionally one needs to cascade three technical blocks --- face localization, facial descriptor construction, and attribute classification --- in a pipeline. As a typical classification problem, face attribute prediction has been addressed using deep learning. Current state-of-the-art performance was achieved by using two cascaded Convolutional Neural Networks (CNNs), which were specifically trained to learn face localization and attribute description. In this paper, we experiment with an alternative way of employing the power of deep representations from CNNs. Combining with conventional face localization techniques, we use off-the-shelf architectures trained for face recognition to build facial descriptors. Recognizing that the describable face attributes are diverse, our face descriptors are constructed from different levels of the CNNs for different attributes to best facilitate face attribute prediction. Experiments on two large datasets, LFWA and CelebA, show that our approach is entirely comparable to the state-of-the-art. Our findings not only demonstrate an efficient face attribute prediction approach, but also raise an important question: how to leverage the power of off-the-shelf CNN representations for novel tasks.
no_new_dataset
0.946597
1605.02699
Saikat Basu
Saikat Basu, Manohar Karki, Robert DiBiano, Supratik Mukhopadhyay, Sangram Ganguly, Ramakrishna Nemani and Shreekant Gayaka
A Theoretical Analysis of Deep Neural Networks for Texture Classification
Accepted in International Joint Conference on Neural Networks, IJCNN 2016
null
null
null
cs.CV cs.LG stat.ML
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We investigate the use of Deep Neural Networks for the classification of image datasets where texture features are important for generating class-conditional discriminative representations. To this end, we first derive the size of the feature space for some standard textural features extracted from the input dataset and then use the theory of Vapnik-Chervonenkis dimension to show that hand-crafted feature extraction creates low-dimensional representations which help in reducing the overall excess error rate. As a corollary to this analysis, we derive for the first time upper bounds on the VC dimension of Convolutional Neural Network as well as Dropout and Dropconnect networks and the relation between excess error rate of Dropout and Dropconnect networks. The concept of intrinsic dimension is used to validate the intuition that texture-based datasets are inherently higher dimensional as compared to handwritten digits or other object recognition datasets and hence more difficult to be shattered by neural networks. We then derive the mean distance from the centroid to the nearest and farthest sampling points in an n-dimensional manifold and show that the Relative Contrast of the sample data vanishes as dimensionality of the underlying vector space tends to infinity.
[ { "version": "v1", "created": "Mon, 9 May 2016 19:11:22 GMT" }, { "version": "v2", "created": "Tue, 21 Jun 2016 19:32:06 GMT" } ]
2016-06-22T00:00:00
[ [ "Basu", "Saikat", "" ], [ "Karki", "Manohar", "" ], [ "DiBiano", "Robert", "" ], [ "Mukhopadhyay", "Supratik", "" ], [ "Ganguly", "Sangram", "" ], [ "Nemani", "Ramakrishna", "" ], [ "Gayaka", "Shreekant", "" ] ]
TITLE: A Theoretical Analysis of Deep Neural Networks for Texture Classification ABSTRACT: We investigate the use of Deep Neural Networks for the classification of image datasets where texture features are important for generating class-conditional discriminative representations. To this end, we first derive the size of the feature space for some standard textural features extracted from the input dataset and then use the theory of Vapnik-Chervonenkis dimension to show that hand-crafted feature extraction creates low-dimensional representations which help in reducing the overall excess error rate. As a corollary to this analysis, we derive for the first time upper bounds on the VC dimension of Convolutional Neural Network as well as Dropout and Dropconnect networks and the relation between excess error rate of Dropout and Dropconnect networks. The concept of intrinsic dimension is used to validate the intuition that texture-based datasets are inherently higher dimensional as compared to handwritten digits or other object recognition datasets and hence more difficult to be shattered by neural networks. We then derive the mean distance from the centroid to the nearest and farthest sampling points in an n-dimensional manifold and show that the Relative Contrast of the sample data vanishes as dimensionality of the underlying vector space tends to infinity.
no_new_dataset
0.947332
1606.06357
Th\'eo Trouillon
Th\'eo Trouillon, Johannes Welbl, Sebastian Riedel, \'Eric Gaussier, Guillaume Bouchard
Complex Embeddings for Simple Link Prediction
10+2 pages, accepted at ICML 2016
null
null
null
cs.AI cs.LG stat.ML
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
In statistical relational learning, the link prediction problem is key to automatically understand the structure of large knowledge bases. As in previous studies, we propose to solve this problem through latent factorization. However, here we make use of complex valued embeddings. The composition of complex embeddings can handle a large variety of binary relations, among them symmetric and antisymmetric relations. Compared to state-of-the-art models such as Neural Tensor Network and Holographic Embeddings, our approach based on complex embeddings is arguably simpler, as it only uses the Hermitian dot product, the complex counterpart of the standard dot product between real vectors. Our approach is scalable to large datasets as it remains linear in both space and time, while consistently outperforming alternative approaches on standard link prediction benchmarks.
[ { "version": "v1", "created": "Mon, 20 Jun 2016 22:52:48 GMT" } ]
2016-06-22T00:00:00
[ [ "Trouillon", "Théo", "" ], [ "Welbl", "Johannes", "" ], [ "Riedel", "Sebastian", "" ], [ "Gaussier", "Éric", "" ], [ "Bouchard", "Guillaume", "" ] ]
TITLE: Complex Embeddings for Simple Link Prediction ABSTRACT: In statistical relational learning, the link prediction problem is key to automatically understand the structure of large knowledge bases. As in previous studies, we propose to solve this problem through latent factorization. However, here we make use of complex valued embeddings. The composition of complex embeddings can handle a large variety of binary relations, among them symmetric and antisymmetric relations. Compared to state-of-the-art models such as Neural Tensor Network and Holographic Embeddings, our approach based on complex embeddings is arguably simpler, as it only uses the Hermitian dot product, the complex counterpart of the standard dot product between real vectors. Our approach is scalable to large datasets as it remains linear in both space and time, while consistently outperforming alternative approaches on standard link prediction benchmarks.
no_new_dataset
0.944074
1606.06437
Raghudeep Gadde
Raghudeep Gadde and Varun Jampani and Renaud Marlet and Peter V. Gehler
Efficient 2D and 3D Facade Segmentation using Auto-Context
8 pages
null
null
null
cs.CV
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
This paper introduces a fast and efficient segmentation technique for 2D images and 3D point clouds of building facades. Facades of buildings are highly structured and consequently most methods that have been proposed for this problem aim to make use of this strong prior information. Contrary to most prior work, we are describing a system that is almost domain independent and consists of standard segmentation methods. We train a sequence of boosted decision trees using auto-context features. This is learned using stacked generalization. We find that this technique performs better, or comparable with all previous published methods and present empirical results on all available 2D and 3D facade benchmark datasets. The proposed method is simple to implement, easy to extend, and very efficient at test-time inference.
[ { "version": "v1", "created": "Tue, 21 Jun 2016 06:50:35 GMT" } ]
2016-06-22T00:00:00
[ [ "Gadde", "Raghudeep", "" ], [ "Jampani", "Varun", "" ], [ "Marlet", "Renaud", "" ], [ "Gehler", "Peter V.", "" ] ]
TITLE: Efficient 2D and 3D Facade Segmentation using Auto-Context ABSTRACT: This paper introduces a fast and efficient segmentation technique for 2D images and 3D point clouds of building facades. Facades of buildings are highly structured and consequently most methods that have been proposed for this problem aim to make use of this strong prior information. Contrary to most prior work, we are describing a system that is almost domain independent and consists of standard segmentation methods. We train a sequence of boosted decision trees using auto-context features. This is learned using stacked generalization. We find that this technique performs better, or comparable with all previous published methods and present empirical results on all available 2D and 3D facade benchmark datasets. The proposed method is simple to implement, easy to extend, and very efficient at test-time inference.
no_new_dataset
0.948202
1410.2386
Qibin Zhao Dr
Qibin Zhao, Guoxu Zhou, Liqing Zhang, Andrzej Cichocki, and Shun-ichi Amari
Bayesian Robust Tensor Factorization for Incomplete Multiway Data
in IEEE Transactions on Neural Networks and Learning Systems, 2015
null
10.1109/TNNLS.2015.2423694
null
cs.CV cs.LG
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We propose a generative model for robust tensor factorization in the presence of both missing data and outliers. The objective is to explicitly infer the underlying low-CP-rank tensor capturing the global information and a sparse tensor capturing the local information (also considered as outliers), thus providing the robust predictive distribution over missing entries. The low-CP-rank tensor is modeled by multilinear interactions between multiple latent factors on which the column sparsity is enforced by a hierarchical prior, while the sparse tensor is modeled by a hierarchical view of Student-$t$ distribution that associates an individual hyperparameter with each element independently. For model learning, we develop an efficient closed-form variational inference under a fully Bayesian treatment, which can effectively prevent the overfitting problem and scales linearly with data size. In contrast to existing related works, our method can perform model selection automatically and implicitly without need of tuning parameters. More specifically, it can discover the groundtruth of CP rank and automatically adapt the sparsity inducing priors to various types of outliers. In addition, the tradeoff between the low-rank approximation and the sparse representation can be optimized in the sense of maximum model evidence. The extensive experiments and comparisons with many state-of-the-art algorithms on both synthetic and real-world datasets demonstrate the superiorities of our method from several perspectives.
[ { "version": "v1", "created": "Thu, 9 Oct 2014 08:50:31 GMT" }, { "version": "v2", "created": "Thu, 16 Apr 2015 05:36:23 GMT" } ]
2016-06-21T00:00:00
[ [ "Zhao", "Qibin", "" ], [ "Zhou", "Guoxu", "" ], [ "Zhang", "Liqing", "" ], [ "Cichocki", "Andrzej", "" ], [ "Amari", "Shun-ichi", "" ] ]
TITLE: Bayesian Robust Tensor Factorization for Incomplete Multiway Data ABSTRACT: We propose a generative model for robust tensor factorization in the presence of both missing data and outliers. The objective is to explicitly infer the underlying low-CP-rank tensor capturing the global information and a sparse tensor capturing the local information (also considered as outliers), thus providing the robust predictive distribution over missing entries. The low-CP-rank tensor is modeled by multilinear interactions between multiple latent factors on which the column sparsity is enforced by a hierarchical prior, while the sparse tensor is modeled by a hierarchical view of Student-$t$ distribution that associates an individual hyperparameter with each element independently. For model learning, we develop an efficient closed-form variational inference under a fully Bayesian treatment, which can effectively prevent the overfitting problem and scales linearly with data size. In contrast to existing related works, our method can perform model selection automatically and implicitly without need of tuning parameters. More specifically, it can discover the groundtruth of CP rank and automatically adapt the sparsity inducing priors to various types of outliers. In addition, the tradeoff between the low-rank approximation and the sparse representation can be optimized in the sense of maximum model evidence. The extensive experiments and comparisons with many state-of-the-art algorithms on both synthetic and real-world datasets demonstrate the superiorities of our method from several perspectives.
no_new_dataset
0.946001
1505.05561
Devansh Arpit
Devansh Arpit, Yingbo Zhou, Hung Ngo, Venu Govindaraju
Why Regularized Auto-Encoders learn Sparse Representation?
8 pages of content, 1 page of reference, 4 pages of supplementary. ICML 2016; bug fix in lemma 1
null
null
null
stat.ML cs.CV cs.LG
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
While the authors of Batch Normalization (BN) identify and address an important problem involved in training deep networks-- \textit{Internal Covariate Shift}-- the current solution has certain drawbacks. For instance, BN depends on batch statistics for layerwise input normalization during training which makes the estimates of mean and standard deviation of input (distribution) to hidden layers inaccurate due to shifting parameter values (especially during initial training epochs). Another fundamental problem with BN is that it cannot be used with batch-size $ 1 $ during training. We address these drawbacks of BN by proposing a non-adaptive normalization technique for removing covariate shift, that we call \textit{Normalization Propagation}. Our approach does not depend on batch statistics, but rather uses a data-independent parametric estimate of mean and standard-deviation in every layer thus being computationally faster compared with BN. We exploit the observation that the pre-activation before Rectified Linear Units follow Gaussian distribution in deep networks, and that once the first and second order statistics of any given dataset are normalized, we can forward propagate this normalization without the need for recalculating the approximate statistics for hidden layers.
[ { "version": "v1", "created": "Thu, 21 May 2015 00:10:46 GMT" }, { "version": "v2", "created": "Fri, 29 May 2015 19:22:37 GMT" }, { "version": "v3", "created": "Wed, 2 Mar 2016 15:29:29 GMT" }, { "version": "v4", "created": "Mon, 23 May 2016 23:04:21 GMT" }, { "version": "v5", "created": "Fri, 17 Jun 2016 23:01:20 GMT" } ]
2016-06-21T00:00:00
[ [ "Arpit", "Devansh", "" ], [ "Zhou", "Yingbo", "" ], [ "Ngo", "Hung", "" ], [ "Govindaraju", "Venu", "" ] ]
TITLE: Why Regularized Auto-Encoders learn Sparse Representation? ABSTRACT: While the authors of Batch Normalization (BN) identify and address an important problem involved in training deep networks-- \textit{Internal Covariate Shift}-- the current solution has certain drawbacks. For instance, BN depends on batch statistics for layerwise input normalization during training which makes the estimates of mean and standard deviation of input (distribution) to hidden layers inaccurate due to shifting parameter values (especially during initial training epochs). Another fundamental problem with BN is that it cannot be used with batch-size $ 1 $ during training. We address these drawbacks of BN by proposing a non-adaptive normalization technique for removing covariate shift, that we call \textit{Normalization Propagation}. Our approach does not depend on batch statistics, but rather uses a data-independent parametric estimate of mean and standard-deviation in every layer thus being computationally faster compared with BN. We exploit the observation that the pre-activation before Rectified Linear Units follow Gaussian distribution in deep networks, and that once the first and second order statistics of any given dataset are normalized, we can forward propagate this normalization without the need for recalculating the approximate statistics for hidden layers.
no_new_dataset
0.944893
1505.07335
Guy Karlebach
Guy Karlebach
A Novel Algorithm for the Maximal Fit Problem in Boolean Networks
null
null
null
null
q-bio.MN cs.CE cs.SI
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Gene regulatory networks (GRNs) are increasingly used for explaining biological processes with complex transcriptional regulation. A GRN links the expression levels of a set of genes via regulatory controls that gene products exert on one another. Boolean networks are a common modeling choice since they balance between detail and ease of analysis. However, even for Boolean networks the problem of fitting a given network model to an expression dataset is NP-Complete. Previous methods have addressed this issue heuristically or by focusing on acyclic networks and specific classes of regulation functions. In this paper we introduce a novel algorithm for this problem that makes use of sampling in order to handle large datasets. Our algorithm can handle time series data for any network type and steady state data for acyclic networks. Using in-silico time series data we demonstrate good performance on large datasets with a significant level of noise.
[ { "version": "v1", "created": "Mon, 25 May 2015 08:12:41 GMT" }, { "version": "v2", "created": "Tue, 31 May 2016 19:32:39 GMT" }, { "version": "v3", "created": "Mon, 20 Jun 2016 02:29:12 GMT" } ]
2016-06-21T00:00:00
[ [ "Karlebach", "Guy", "" ] ]
TITLE: A Novel Algorithm for the Maximal Fit Problem in Boolean Networks ABSTRACT: Gene regulatory networks (GRNs) are increasingly used for explaining biological processes with complex transcriptional regulation. A GRN links the expression levels of a set of genes via regulatory controls that gene products exert on one another. Boolean networks are a common modeling choice since they balance between detail and ease of analysis. However, even for Boolean networks the problem of fitting a given network model to an expression dataset is NP-Complete. Previous methods have addressed this issue heuristically or by focusing on acyclic networks and specific classes of regulation functions. In this paper we introduce a novel algorithm for this problem that makes use of sampling in order to handle large datasets. Our algorithm can handle time series data for any network type and steady state data for acyclic networks. Using in-silico time series data we demonstrate good performance on large datasets with a significant level of noise.
no_new_dataset
0.949669
1508.01983
Amr Bakry
Amr Bakry, Mohamed Elhoseiny, Tarek El-Gaaly and Ahmed Elgammal
Digging Deep into the layers of CNNs: In Search of How CNNs Achieve View Invariance
This paper accepted in ICLR 2016 main conference
null
null
null
cs.CV
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
This paper is focused on studying the view-manifold structure in the feature spaces implied by the different layers of Convolutional Neural Networks (CNN). There are several questions that this paper aims to answer: Does the learned CNN representation achieve viewpoint invariance? How does it achieve viewpoint invariance? Is it achieved by collapsing the view manifolds, or separating them while preserving them? At which layer is view invariance achieved? How can the structure of the view manifold at each layer of a deep convolutional neural network be quantified experimentally? How does fine-tuning of a pre-trained CNN on a multi-view dataset affect the representation at each layer of the network? In order to answer these questions we propose a methodology to quantify the deformation and degeneracy of view manifolds in CNN layers. We apply this methodology and report interesting results in this paper that answer the aforementioned questions.
[ { "version": "v1", "created": "Sun, 9 Aug 2015 04:02:51 GMT" }, { "version": "v2", "created": "Fri, 20 Nov 2015 09:22:40 GMT" }, { "version": "v3", "created": "Fri, 8 Jan 2016 06:56:49 GMT" }, { "version": "v4", "created": "Mon, 20 Jun 2016 10:05:15 GMT" } ]
2016-06-21T00:00:00
[ [ "Bakry", "Amr", "" ], [ "Elhoseiny", "Mohamed", "" ], [ "El-Gaaly", "Tarek", "" ], [ "Elgammal", "Ahmed", "" ] ]
TITLE: Digging Deep into the layers of CNNs: In Search of How CNNs Achieve View Invariance ABSTRACT: This paper is focused on studying the view-manifold structure in the feature spaces implied by the different layers of Convolutional Neural Networks (CNN). There are several questions that this paper aims to answer: Does the learned CNN representation achieve viewpoint invariance? How does it achieve viewpoint invariance? Is it achieved by collapsing the view manifolds, or separating them while preserving them? At which layer is view invariance achieved? How can the structure of the view manifold at each layer of a deep convolutional neural network be quantified experimentally? How does fine-tuning of a pre-trained CNN on a multi-view dataset affect the representation at each layer of the network? In order to answer these questions we propose a methodology to quantify the deformation and degeneracy of view manifolds in CNN layers. We apply this methodology and report interesting results in this paper that answer the aforementioned questions.
no_new_dataset
0.946597
1601.07140
Andreas Veit
Andreas Veit and Tomas Matera and Lukas Neumann and Jiri Matas and Serge Belongie
COCO-Text: Dataset and Benchmark for Text Detection and Recognition in Natural Images
null
null
null
null
cs.CV
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
This paper describes the COCO-Text dataset. In recent years large-scale datasets like SUN and Imagenet drove the advancement of scene understanding and object recognition. The goal of COCO-Text is to advance state-of-the-art in text detection and recognition in natural images. The dataset is based on the MS COCO dataset, which contains images of complex everyday scenes. The images were not collected with text in mind and thus contain a broad variety of text instances. To reflect the diversity of text in natural scenes, we annotate text with (a) location in terms of a bounding box, (b) fine-grained classification into machine printed text and handwritten text, (c) classification into legible and illegible text, (d) script of the text and (e) transcriptions of legible text. The dataset contains over 173k text annotations in over 63k images. We provide a statistical analysis of the accuracy of our annotations. In addition, we present an analysis of three leading state-of-the-art photo Optical Character Recognition (OCR) approaches on our dataset. While scene text detection and recognition enjoys strong advances in recent years, we identify significant shortcomings motivating future work.
[ { "version": "v1", "created": "Tue, 26 Jan 2016 19:30:34 GMT" }, { "version": "v2", "created": "Sun, 19 Jun 2016 23:52:14 GMT" } ]
2016-06-21T00:00:00
[ [ "Veit", "Andreas", "" ], [ "Matera", "Tomas", "" ], [ "Neumann", "Lukas", "" ], [ "Matas", "Jiri", "" ], [ "Belongie", "Serge", "" ] ]
TITLE: COCO-Text: Dataset and Benchmark for Text Detection and Recognition in Natural Images ABSTRACT: This paper describes the COCO-Text dataset. In recent years large-scale datasets like SUN and Imagenet drove the advancement of scene understanding and object recognition. The goal of COCO-Text is to advance state-of-the-art in text detection and recognition in natural images. The dataset is based on the MS COCO dataset, which contains images of complex everyday scenes. The images were not collected with text in mind and thus contain a broad variety of text instances. To reflect the diversity of text in natural scenes, we annotate text with (a) location in terms of a bounding box, (b) fine-grained classification into machine printed text and handwritten text, (c) classification into legible and illegible text, (d) script of the text and (e) transcriptions of legible text. The dataset contains over 173k text annotations in over 63k images. We provide a statistical analysis of the accuracy of our annotations. In addition, we present an analysis of three leading state-of-the-art photo Optical Character Recognition (OCR) approaches on our dataset. While scene text detection and recognition enjoys strong advances in recent years, we identify significant shortcomings motivating future work.
new_dataset
0.953319
1601.07255
Chunhua Shen
Lin Wu, Chunhua Shen, Anton van den Hengel
PersonNet: Person Re-identification with Deep Convolutional Neural Networks
7 pages. Fixed Figure 4 (a)
null
null
null
cs.CV
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
In this paper, we propose a deep end-to-end neu- ral network to simultaneously learn high-level features and a corresponding similarity metric for person re-identification. The network takes a pair of raw RGB images as input, and outputs a similarity value indicating whether the two input images depict the same person. A layer of computing neighborhood range differences across two input images is employed to capture local relationship between patches. This operation is to seek a robust feature from input images. By increasing the depth to 10 weight layers and using very small (3$\times$3) convolution filters, our architecture achieves a remarkable improvement on the prior-art configurations. Meanwhile, an adaptive Root- Mean-Square (RMSProp) gradient decent algorithm is integrated into our architecture, which is beneficial to deep nets. Our method consistently outperforms state-of-the-art on two large datasets (CUHK03 and Market-1501), and a medium-sized data set (CUHK01).
[ { "version": "v1", "created": "Wed, 27 Jan 2016 03:49:34 GMT" }, { "version": "v2", "created": "Mon, 20 Jun 2016 06:43:54 GMT" } ]
2016-06-21T00:00:00
[ [ "Wu", "Lin", "" ], [ "Shen", "Chunhua", "" ], [ "Hengel", "Anton van den", "" ] ]
TITLE: PersonNet: Person Re-identification with Deep Convolutional Neural Networks ABSTRACT: In this paper, we propose a deep end-to-end neu- ral network to simultaneously learn high-level features and a corresponding similarity metric for person re-identification. The network takes a pair of raw RGB images as input, and outputs a similarity value indicating whether the two input images depict the same person. A layer of computing neighborhood range differences across two input images is employed to capture local relationship between patches. This operation is to seek a robust feature from input images. By increasing the depth to 10 weight layers and using very small (3$\times$3) convolution filters, our architecture achieves a remarkable improvement on the prior-art configurations. Meanwhile, an adaptive Root- Mean-Square (RMSProp) gradient decent algorithm is integrated into our architecture, which is beneficial to deep nets. Our method consistently outperforms state-of-the-art on two large datasets (CUHK03 and Market-1501), and a medium-sized data set (CUHK01).
no_new_dataset
0.946745
1602.04256
Yihan Gao
Yihan Gao, Aditya Parameswaran
Squish: Near-Optimal Compression for Archival of Relational Datasets
null
null
10.1145/2939672.2939867
null
cs.DB
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Relational datasets are being generated at an alarmingly rapid rate across organizations and industries. Compressing these datasets could significantly reduce storage and archival costs. Traditional compression algorithms, e.g., gzip, are suboptimal for compressing relational datasets since they ignore the table structure and relationships between attributes. We study compression algorithms that leverage the relational structure to compress datasets to a much greater extent. We develop Squish, a system that uses a combination of Bayesian Networks and Arithmetic Coding to capture multiple kinds of dependencies among attributes and achieve near-entropy compression rate. Squish also supports user-defined attributes: users can instantiate new data types by simply implementing five functions for a new class interface. We prove the asymptotic optimality of our compression algorithm and conduct experiments to show the effectiveness of our system: Squish achieves a reduction of over 50\% in storage size relative to systems developed in prior work on a variety of real datasets.
[ { "version": "v1", "created": "Fri, 12 Feb 2016 22:46:57 GMT" }, { "version": "v2", "created": "Sun, 19 Jun 2016 16:09:39 GMT" } ]
2016-06-21T00:00:00
[ [ "Gao", "Yihan", "" ], [ "Parameswaran", "Aditya", "" ] ]
TITLE: Squish: Near-Optimal Compression for Archival of Relational Datasets ABSTRACT: Relational datasets are being generated at an alarmingly rapid rate across organizations and industries. Compressing these datasets could significantly reduce storage and archival costs. Traditional compression algorithms, e.g., gzip, are suboptimal for compressing relational datasets since they ignore the table structure and relationships between attributes. We study compression algorithms that leverage the relational structure to compress datasets to a much greater extent. We develop Squish, a system that uses a combination of Bayesian Networks and Arithmetic Coding to capture multiple kinds of dependencies among attributes and achieve near-entropy compression rate. Squish also supports user-defined attributes: users can instantiate new data types by simply implementing five functions for a new class interface. We prove the asymptotic optimality of our compression algorithm and conduct experiments to show the effectiveness of our system: Squish achieves a reduction of over 50\% in storage size relative to systems developed in prior work on a variety of real datasets.
no_new_dataset
0.943348
1603.00223
Liang Lu
Liang Lu, Lingpeng Kong, Chris Dyer, Noah A. Smith and Steve Renals
Segmental Recurrent Neural Networks for End-to-end Speech Recognition
5 pages, 2 figures, accepted by Interspeech 2016
null
null
null
cs.CL cs.LG cs.NE
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We study the segmental recurrent neural network for end-to-end acoustic modelling. This model connects the segmental conditional random field (CRF) with a recurrent neural network (RNN) used for feature extraction. Compared to most previous CRF-based acoustic models, it does not rely on an external system to provide features or segmentation boundaries. Instead, this model marginalises out all the possible segmentations, and features are extracted from the RNN trained together with the segmental CRF. In essence, this model is self-contained and can be trained end-to-end. In this paper, we discuss practical training and decoding issues as well as the method to speed up the training in the context of speech recognition. We performed experiments on the TIMIT dataset. We achieved 17.3 phone error rate (PER) from the first-pass decoding --- the best reported result using CRFs, despite the fact that we only used a zeroth-order CRF and without using any language model.
[ { "version": "v1", "created": "Tue, 1 Mar 2016 10:43:43 GMT" }, { "version": "v2", "created": "Mon, 20 Jun 2016 10:29:23 GMT" } ]
2016-06-21T00:00:00
[ [ "Lu", "Liang", "" ], [ "Kong", "Lingpeng", "" ], [ "Dyer", "Chris", "" ], [ "Smith", "Noah A.", "" ], [ "Renals", "Steve", "" ] ]
TITLE: Segmental Recurrent Neural Networks for End-to-end Speech Recognition ABSTRACT: We study the segmental recurrent neural network for end-to-end acoustic modelling. This model connects the segmental conditional random field (CRF) with a recurrent neural network (RNN) used for feature extraction. Compared to most previous CRF-based acoustic models, it does not rely on an external system to provide features or segmentation boundaries. Instead, this model marginalises out all the possible segmentations, and features are extracted from the RNN trained together with the segmental CRF. In essence, this model is self-contained and can be trained end-to-end. In this paper, we discuss practical training and decoding issues as well as the method to speed up the training in the context of speech recognition. We performed experiments on the TIMIT dataset. We achieved 17.3 phone error rate (PER) from the first-pass decoding --- the best reported result using CRFs, despite the fact that we only used a zeroth-order CRF and without using any language model.
no_new_dataset
0.952574
1604.03628
Jianwei Yang
Jianwei Yang, Devi Parikh, Dhruv Batra
Joint Unsupervised Learning of Deep Representations and Image Clusters
19 pages, 11 figures, 14 tables, 2016 IEEE Conference on Computer Vision and Pattern Recognition (CVPR)
null
null
null
cs.CV cs.LG
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
In this paper, we propose a recurrent framework for Joint Unsupervised LEarning (JULE) of deep representations and image clusters. In our framework, successive operations in a clustering algorithm are expressed as steps in a recurrent process, stacked on top of representations output by a Convolutional Neural Network (CNN). During training, image clusters and representations are updated jointly: image clustering is conducted in the forward pass, while representation learning in the backward pass. Our key idea behind this framework is that good representations are beneficial to image clustering and clustering results provide supervisory signals to representation learning. By integrating two processes into a single model with a unified weighted triplet loss and optimizing it end-to-end, we can obtain not only more powerful representations, but also more precise image clusters. Extensive experiments show that our method outperforms the state-of-the-art on image clustering across a variety of image datasets. Moreover, the learned representations generalize well when transferred to other tasks.
[ { "version": "v1", "created": "Wed, 13 Apr 2016 01:24:59 GMT" }, { "version": "v2", "created": "Wed, 25 May 2016 19:45:59 GMT" }, { "version": "v3", "created": "Mon, 20 Jun 2016 19:56:16 GMT" } ]
2016-06-21T00:00:00
[ [ "Yang", "Jianwei", "" ], [ "Parikh", "Devi", "" ], [ "Batra", "Dhruv", "" ] ]
TITLE: Joint Unsupervised Learning of Deep Representations and Image Clusters ABSTRACT: In this paper, we propose a recurrent framework for Joint Unsupervised LEarning (JULE) of deep representations and image clusters. In our framework, successive operations in a clustering algorithm are expressed as steps in a recurrent process, stacked on top of representations output by a Convolutional Neural Network (CNN). During training, image clusters and representations are updated jointly: image clustering is conducted in the forward pass, while representation learning in the backward pass. Our key idea behind this framework is that good representations are beneficial to image clustering and clustering results provide supervisory signals to representation learning. By integrating two processes into a single model with a unified weighted triplet loss and optimizing it end-to-end, we can obtain not only more powerful representations, but also more precise image clusters. Extensive experiments show that our method outperforms the state-of-the-art on image clustering across a variety of image datasets. Moreover, the learned representations generalize well when transferred to other tasks.
no_new_dataset
0.947672
1604.05592
Angjoo Kanazawa
Angjoo Kanazawa and David W. Jacobs and Manmohan Chandraker
WarpNet: Weakly Supervised Matching for Single-view Reconstruction
to appear in IEEE Conference on Computer Vision and Pattern Recognition (CVPR) 2016
null
null
null
cs.CV
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We present an approach to matching images of objects in fine-grained datasets without using part annotations, with an application to the challenging problem of weakly supervised single-view reconstruction. This is in contrast to prior works that require part annotations, since matching objects across class and pose variations is challenging with appearance features alone. We overcome this challenge through a novel deep learning architecture, WarpNet, that aligns an object in one image with a different object in another. We exploit the structure of the fine-grained dataset to create artificial data for training this network in an unsupervised-discriminative learning approach. The output of the network acts as a spatial prior that allows generalization at test time to match real images across variations in appearance, viewpoint and articulation. On the CUB-200-2011 dataset of bird categories, we improve the AP over an appearance-only network by 13.6%. We further demonstrate that our WarpNet matches, together with the structure of fine-grained datasets, allow single-view reconstructions with quality comparable to using annotated point correspondences.
[ { "version": "v1", "created": "Tue, 19 Apr 2016 14:28:42 GMT" }, { "version": "v2", "created": "Mon, 20 Jun 2016 09:40:46 GMT" } ]
2016-06-21T00:00:00
[ [ "Kanazawa", "Angjoo", "" ], [ "Jacobs", "David W.", "" ], [ "Chandraker", "Manmohan", "" ] ]
TITLE: WarpNet: Weakly Supervised Matching for Single-view Reconstruction ABSTRACT: We present an approach to matching images of objects in fine-grained datasets without using part annotations, with an application to the challenging problem of weakly supervised single-view reconstruction. This is in contrast to prior works that require part annotations, since matching objects across class and pose variations is challenging with appearance features alone. We overcome this challenge through a novel deep learning architecture, WarpNet, that aligns an object in one image with a different object in another. We exploit the structure of the fine-grained dataset to create artificial data for training this network in an unsupervised-discriminative learning approach. The output of the network acts as a spatial prior that allows generalization at test time to match real images across variations in appearance, viewpoint and articulation. On the CUB-200-2011 dataset of bird categories, we improve the AP over an appearance-only network by 13.6%. We further demonstrate that our WarpNet matches, together with the structure of fine-grained datasets, allow single-view reconstructions with quality comparable to using annotated point correspondences.
no_new_dataset
0.951188
1606.05694
Soroush Vosoughi Dr
Prashanth Vijayaraghavan, Ivan Sysoev, Soroush Vosoughi and Deb Roy
DeepStance at SemEval-2016 Task 6: Detecting Stance in Tweets Using Character and Word-Level CNNs
SemEval 2016, San Diego, California. In Proceedings of the 10th International Workshop on Semantic Evaluation (SemEval-2016). San Diego, California
null
null
null
cs.CL cs.SI
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
This paper describes our approach for the Detecting Stance in Tweets task (SemEval-2016 Task 6). We utilized recent advances in short text categorization using deep learning to create word-level and character-level models. The choice between word-level and character-level models in each particular case was informed through validation performance. Our final system is a combination of classifiers using word-level or character-level models. We also employed novel data augmentation techniques to expand and diversify our training dataset, thus making our system more robust. Our system achieved a macro-average precision, recall and F1-scores of 0.67, 0.61 and 0.635 respectively.
[ { "version": "v1", "created": "Fri, 17 Jun 2016 22:32:50 GMT" } ]
2016-06-21T00:00:00
[ [ "Vijayaraghavan", "Prashanth", "" ], [ "Sysoev", "Ivan", "" ], [ "Vosoughi", "Soroush", "" ], [ "Roy", "Deb", "" ] ]
TITLE: DeepStance at SemEval-2016 Task 6: Detecting Stance in Tweets Using Character and Word-Level CNNs ABSTRACT: This paper describes our approach for the Detecting Stance in Tweets task (SemEval-2016 Task 6). We utilized recent advances in short text categorization using deep learning to create word-level and character-level models. The choice between word-level and character-level models in each particular case was informed through validation performance. Our final system is a combination of classifiers using word-level or character-level models. We also employed novel data augmentation techniques to expand and diversify our training dataset, thus making our system more robust. Our system achieved a macro-average precision, recall and F1-scores of 0.67, 0.61 and 0.635 respectively.
no_new_dataset
0.950457
1606.05699
Lu Wang
Lu Wang and Claire Cardie and Galen Marchetti
Socially-Informed Timeline Generation for Complex Events
NAACL 2015
null
null
null
cs.CL
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Existing timeline generation systems for complex events consider only information from traditional media, ignoring the rich social context provided by user-generated content that reveals representative public interests or insightful opinions. We instead aim to generate socially-informed timelines that contain both news article summaries and selected user comments. We present an optimization framework designed to balance topical cohesion between the article and comment summaries along with their informativeness and coverage of the event. Automatic evaluations on real-world datasets that cover four complex events show that our system produces more informative timelines than state-of-the-art systems. In human evaluation, the associated comment summaries are furthermore rated more insightful than editor's picks and comments ranked highly by users.
[ { "version": "v1", "created": "Fri, 17 Jun 2016 22:52:09 GMT" } ]
2016-06-21T00:00:00
[ [ "Wang", "Lu", "" ], [ "Cardie", "Claire", "" ], [ "Marchetti", "Galen", "" ] ]
TITLE: Socially-Informed Timeline Generation for Complex Events ABSTRACT: Existing timeline generation systems for complex events consider only information from traditional media, ignoring the rich social context provided by user-generated content that reveals representative public interests or insightful opinions. We instead aim to generate socially-informed timelines that contain both news article summaries and selected user comments. We present an optimization framework designed to balance topical cohesion between the article and comment summaries along with their informativeness and coverage of the event. Automatic evaluations on real-world datasets that cover four complex events show that our system produces more informative timelines than state-of-the-art systems. In human evaluation, the associated comment summaries are furthermore rated more insightful than editor's picks and comments ranked highly by users.
no_new_dataset
0.951414
1606.05706
Lu Wang
Lu Wang and Claire Cardie
Improving Agreement and Disagreement Identification in Online Discussions with A Socially-Tuned Sentiment Lexicon
ACL WASSA workshop 2014
null
null
null
cs.CL
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We study the problem of agreement and disagreement detection in online discussions. An isotonic Conditional Random Fields (isotonic CRF) based sequential model is proposed to make predictions on sentence- or segment-level. We automatically construct a socially-tuned lexicon that is bootstrapped from existing general-purpose sentiment lexicons to further improve the performance. We evaluate our agreement and disagreement tagging model on two disparate online discussion corpora -- Wikipedia Talk pages and online debates. Our model is shown to outperform the state-of-the-art approaches in both datasets. For example, the isotonic CRF model achieves F1 scores of 0.74 and 0.67 for agreement and disagreement detection, when a linear chain CRF obtains 0.58 and 0.56 for the discussions on Wikipedia Talk pages.
[ { "version": "v1", "created": "Fri, 17 Jun 2016 23:29:11 GMT" } ]
2016-06-21T00:00:00
[ [ "Wang", "Lu", "" ], [ "Cardie", "Claire", "" ] ]
TITLE: Improving Agreement and Disagreement Identification in Online Discussions with A Socially-Tuned Sentiment Lexicon ABSTRACT: We study the problem of agreement and disagreement detection in online discussions. An isotonic Conditional Random Fields (isotonic CRF) based sequential model is proposed to make predictions on sentence- or segment-level. We automatically construct a socially-tuned lexicon that is bootstrapped from existing general-purpose sentiment lexicons to further improve the performance. We evaluate our agreement and disagreement tagging model on two disparate online discussion corpora -- Wikipedia Talk pages and online debates. Our model is shown to outperform the state-of-the-art approaches in both datasets. For example, the isotonic CRF model achieves F1 scores of 0.74 and 0.67 for agreement and disagreement detection, when a linear chain CRF obtains 0.58 and 0.56 for the discussions on Wikipedia Talk pages.
no_new_dataset
0.948965
1606.05708
Kristi Morton
Kristi Morton, Hannaneh Hajishirzi, Magdalena Balazinska, Dan Grossman
View-Driven Deduplication with Active Learning
13 pgs
null
null
null
cs.DB
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Visual analytics systems such as Tableau are increasingly popular for interactive data exploration. These tools, however, do not currently assist users with detecting or resolving potential data quality problems including the well-known deduplication problem. Recent approaches for deduplication focus on cleaning entire datasets and commonly require hundreds to thousands of user labels. In this paper, we address the problem of deduplication in the context of visual data analytics. We present a new approach for record deduplication that strives to produce the cleanest view possible with a limited budget for data labeling. The key idea behind our approach is to consider the impact that individual tuples have on a visualization and to monitor how the view changes during cleaning. With experiments on nine different visualizations for two real-world datasets, we show that our approach produces significantly cleaner views for small labeling budgets than state-of-the-art alternatives and that it also stops the cleaning process after requesting fewer labels.
[ { "version": "v1", "created": "Fri, 17 Jun 2016 23:38:51 GMT" } ]
2016-06-21T00:00:00
[ [ "Morton", "Kristi", "" ], [ "Hajishirzi", "Hannaneh", "" ], [ "Balazinska", "Magdalena", "" ], [ "Grossman", "Dan", "" ] ]
TITLE: View-Driven Deduplication with Active Learning ABSTRACT: Visual analytics systems such as Tableau are increasingly popular for interactive data exploration. These tools, however, do not currently assist users with detecting or resolving potential data quality problems including the well-known deduplication problem. Recent approaches for deduplication focus on cleaning entire datasets and commonly require hundreds to thousands of user labels. In this paper, we address the problem of deduplication in the context of visual data analytics. We present a new approach for record deduplication that strives to produce the cleanest view possible with a limited budget for data labeling. The key idea behind our approach is to consider the impact that individual tuples have on a visualization and to monitor how the view changes during cleaning. With experiments on nine different visualizations for two real-world datasets, we show that our approach produces significantly cleaner views for small labeling budgets than state-of-the-art alternatives and that it also stops the cleaning process after requesting fewer labels.
no_new_dataset
0.951594
1606.05725
Amirhossein Akbarnejad
Amirhossein Akbarnejad, Mahdieh Soleymani Baghshah
An Efficient Large-scale Semi-supervised Multi-label Classifier Capable of Handling Missing labels
null
null
null
null
cs.LG cs.AI stat.ML
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Multi-label classification has received considerable interest in recent years. Multi-label classifiers have to address many problems including: handling large-scale datasets with many instances and a large set of labels, compensating missing label assignments in the training set, considering correlations between labels, as well as exploiting unlabeled data to improve prediction performance. To tackle datasets with a large set of labels, embedding-based methods have been proposed which seek to represent the label assignments in a low-dimensional space. Many state-of-the-art embedding-based methods use a linear dimensionality reduction to represent the label assignments in a low-dimensional space. However, by doing so, these methods actually neglect the tail labels - labels that are infrequently assigned to instances. We propose an embedding-based method that non-linearly embeds the label vectors using an stochastic approach, thereby predicting the tail labels more accurately. Moreover, the proposed method have excellent mechanisms for handling missing labels, dealing with large-scale datasets, as well as exploiting unlabeled data. With the best of our knowledge, our proposed method is the first multi-label classifier that simultaneously addresses all of the mentioned challenges. Experiments on real-world datasets show that our method outperforms stateof-the-art multi-label classifiers by a large margin, in terms of prediction performance, as well as training time.
[ { "version": "v1", "created": "Sat, 18 Jun 2016 07:49:13 GMT" } ]
2016-06-21T00:00:00
[ [ "Akbarnejad", "Amirhossein", "" ], [ "Baghshah", "Mahdieh Soleymani", "" ] ]
TITLE: An Efficient Large-scale Semi-supervised Multi-label Classifier Capable of Handling Missing labels ABSTRACT: Multi-label classification has received considerable interest in recent years. Multi-label classifiers have to address many problems including: handling large-scale datasets with many instances and a large set of labels, compensating missing label assignments in the training set, considering correlations between labels, as well as exploiting unlabeled data to improve prediction performance. To tackle datasets with a large set of labels, embedding-based methods have been proposed which seek to represent the label assignments in a low-dimensional space. Many state-of-the-art embedding-based methods use a linear dimensionality reduction to represent the label assignments in a low-dimensional space. However, by doing so, these methods actually neglect the tail labels - labels that are infrequently assigned to instances. We propose an embedding-based method that non-linearly embeds the label vectors using an stochastic approach, thereby predicting the tail labels more accurately. Moreover, the proposed method have excellent mechanisms for handling missing labels, dealing with large-scale datasets, as well as exploiting unlabeled data. With the best of our knowledge, our proposed method is the first multi-label classifier that simultaneously addresses all of the mentioned challenges. Experiments on real-world datasets show that our method outperforms stateof-the-art multi-label classifiers by a large margin, in terms of prediction performance, as well as training time.
no_new_dataset
0.948155
1606.05730
Ruocheng Guo
Ruocheng Guo, Paulo Shakarian
A Comparison of Methods for Cascade Prediction
8 pages, 29 figures, ASONAM 2016 (Industry Track)
null
null
null
cs.SI physics.soc-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Information cascades exist in a wide variety of platforms on Internet. A very important real-world problem is to identify which information cascades can go viral. A system addressing this problem can be used in a variety of applications including public health, marketing and counter-terrorism. As a cascade can be considered as compound of the social network and the time series. However, in related literature where methods for solving the cascade prediction problem were proposed, the experimental settings were often limited to only a single metric for a specific problem formulation. Moreover, little attention was paid to the run time of those methods. In this paper, we first formulate the cascade prediction problem as both classification and regression. Then we compare three categories of cascade prediction methods: centrality based, feature based and point process based. We carry out the comparison through evaluation of the methods by both accuracy metrics and run time. The results show that feature based methods can outperform others in terms of prediction accuracy but suffer from heavy overhead especially for large datasets. While point process based methods can also run into issue of long run time when the model can not well adapt to the data. This paper seeks to address issues in order to allow developers of systems for social network analysis to select the most appropriate method for predicting viral information cascades.
[ { "version": "v1", "created": "Sat, 18 Jun 2016 08:41:16 GMT" } ]
2016-06-21T00:00:00
[ [ "Guo", "Ruocheng", "" ], [ "Shakarian", "Paulo", "" ] ]
TITLE: A Comparison of Methods for Cascade Prediction ABSTRACT: Information cascades exist in a wide variety of platforms on Internet. A very important real-world problem is to identify which information cascades can go viral. A system addressing this problem can be used in a variety of applications including public health, marketing and counter-terrorism. As a cascade can be considered as compound of the social network and the time series. However, in related literature where methods for solving the cascade prediction problem were proposed, the experimental settings were often limited to only a single metric for a specific problem formulation. Moreover, little attention was paid to the run time of those methods. In this paper, we first formulate the cascade prediction problem as both classification and regression. Then we compare three categories of cascade prediction methods: centrality based, feature based and point process based. We carry out the comparison through evaluation of the methods by both accuracy metrics and run time. The results show that feature based methods can outperform others in terms of prediction accuracy but suffer from heavy overhead especially for large datasets. While point process based methods can also run into issue of long run time when the model can not well adapt to the data. This paper seeks to address issues in order to allow developers of systems for social network analysis to select the most appropriate method for predicting viral information cascades.
no_new_dataset
0.94743
1606.05752
Chuxu Zhang
Chuxu Zhang, Chuang Liu, Lu Yu, Zi-Ke Zhang and Tao Zhou
Identifying the Academic Rising Stars
12 pages
null
null
null
cs.DL
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Predicting the fast-rising young researchers (Academic Rising Stars) in the future provides useful guidance to the research community, e.g., offering competitive candidates to university for young faculty hiring as they are expected to have success academic careers. In this work, given a set of young researchers who have published the first first-author paper recently, we solve the problem of how to effectively predict the top k% researchers who achieve the highest citation increment in \Delta t years. We explore a series of factors that can drive an author to be fast-rising and design a novel impact increment ranking learning (IIRL) algorithm that leverages those factors to predict the academic rising stars. Experimental results on the large ArnetMiner dataset with over 1.7 million authors demonstrate the effectiveness of IIRL. Specifically, it outperforms all given benchmark methods, with over 8% average improvement. Further analysis demonstrates that the prediction models for different research topics follow the similar pattern. We also find that temporal features are the best indicators for rising stars prediction, while venue features are less relevant.
[ { "version": "v1", "created": "Sat, 18 Jun 2016 14:01:55 GMT" } ]
2016-06-21T00:00:00
[ [ "Zhang", "Chuxu", "" ], [ "Liu", "Chuang", "" ], [ "Yu", "Lu", "" ], [ "Zhang", "Zi-Ke", "" ], [ "Zhou", "Tao", "" ] ]
TITLE: Identifying the Academic Rising Stars ABSTRACT: Predicting the fast-rising young researchers (Academic Rising Stars) in the future provides useful guidance to the research community, e.g., offering competitive candidates to university for young faculty hiring as they are expected to have success academic careers. In this work, given a set of young researchers who have published the first first-author paper recently, we solve the problem of how to effectively predict the top k% researchers who achieve the highest citation increment in \Delta t years. We explore a series of factors that can drive an author to be fast-rising and design a novel impact increment ranking learning (IIRL) algorithm that leverages those factors to predict the academic rising stars. Experimental results on the large ArnetMiner dataset with over 1.7 million authors demonstrate the effectiveness of IIRL. Specifically, it outperforms all given benchmark methods, with over 8% average improvement. Further analysis demonstrates that the prediction models for different research topics follow the similar pattern. We also find that temporal features are the best indicators for rising stars prediction, while venue features are less relevant.
no_new_dataset
0.946597
1606.05814
Kyle Krafka
Kyle Krafka and Aditya Khosla and Petr Kellnhofer and Harini Kannan and Suchendra Bhandarkar and Wojciech Matusik and Antonio Torralba
Eye Tracking for Everyone
The IEEE Conference on Computer Vision and Pattern Recognition (CVPR), 2016
null
null
null
cs.CV
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
From scientific research to commercial applications, eye tracking is an important tool across many domains. Despite its range of applications, eye tracking has yet to become a pervasive technology. We believe that we can put the power of eye tracking in everyone's palm by building eye tracking software that works on commodity hardware such as mobile phones and tablets, without the need for additional sensors or devices. We tackle this problem by introducing GazeCapture, the first large-scale dataset for eye tracking, containing data from over 1450 people consisting of almost 2.5M frames. Using GazeCapture, we train iTracker, a convolutional neural network for eye tracking, which achieves a significant reduction in error over previous approaches while running in real time (10-15fps) on a modern mobile device. Our model achieves a prediction error of 1.71cm and 2.53cm without calibration on mobile phones and tablets respectively. With calibration, this is reduced to 1.34cm and 2.12cm. Further, we demonstrate that the features learned by iTracker generalize well to other datasets, achieving state-of-the-art results. The code, data, and models are available at http://gazecapture.csail.mit.edu.
[ { "version": "v1", "created": "Sat, 18 Jun 2016 23:53:54 GMT" } ]
2016-06-21T00:00:00
[ [ "Krafka", "Kyle", "" ], [ "Khosla", "Aditya", "" ], [ "Kellnhofer", "Petr", "" ], [ "Kannan", "Harini", "" ], [ "Bhandarkar", "Suchendra", "" ], [ "Matusik", "Wojciech", "" ], [ "Torralba", "Antonio", "" ] ]
TITLE: Eye Tracking for Everyone ABSTRACT: From scientific research to commercial applications, eye tracking is an important tool across many domains. Despite its range of applications, eye tracking has yet to become a pervasive technology. We believe that we can put the power of eye tracking in everyone's palm by building eye tracking software that works on commodity hardware such as mobile phones and tablets, without the need for additional sensors or devices. We tackle this problem by introducing GazeCapture, the first large-scale dataset for eye tracking, containing data from over 1450 people consisting of almost 2.5M frames. Using GazeCapture, we train iTracker, a convolutional neural network for eye tracking, which achieves a significant reduction in error over previous approaches while running in real time (10-15fps) on a modern mobile device. Our model achieves a prediction error of 1.71cm and 2.53cm without calibration on mobile phones and tablets respectively. With calibration, this is reduced to 1.34cm and 2.12cm. Further, we demonstrate that the features learned by iTracker generalize well to other datasets, achieving state-of-the-art results. The code, data, and models are available at http://gazecapture.csail.mit.edu.
new_dataset
0.957118
1606.05893
Neil Zhenqiang Gong
Neil Zhenqiang Gong and Bin Liu
You are Who You Know and How You Behave: Attribute Inference Attacks via Users' Social Friends and Behaviors
Usenix Security Symposium 2016
null
null
null
cs.SI physics.soc-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We propose new privacy attacks to infer attributes (e.g., locations, occupations, and interests) of online social network users. Our attacks leverage seemingly innocent user information that is publicly available in online social networks to infer missing attributes of targeted users. Given the increasing availability of (seemingly innocent) user information online, our results have serious implications for Internet privacy -- private attributes can be inferred from users' publicly available data unless we take steps to protect users from such inference attacks. To infer attributes of a targeted user, existing inference attacks leverage either the user's publicly available social friends or the user's behavioral records (e.g., the webpages that the user has liked on Facebook, the apps that the user has reviewed on Google Play), but not both. As we will show, such inference attacks achieve limited success rates. However, the problem becomes qualitatively different if we consider both social friends and behavioral records. To address this challenge, we develop a novel model to integrate social friends and behavioral records and design new attacks based on our model. We theoretically and experimentally demonstrate the effectiveness of our attacks. For instance, we observe that, in a real-world large-scale dataset with 1.1 million users, our attack can correctly infer the cities a user lived in for 57% of the users, via confidence estimation, we are able to increase the attack success rate to over 90% if the attacker selectively attacks a half of the users. Moreover, we show that our attack can correctly infer attributes for significantly more users than previous attacks.
[ { "version": "v1", "created": "Sun, 19 Jun 2016 17:34:50 GMT" } ]
2016-06-21T00:00:00
[ [ "Gong", "Neil Zhenqiang", "" ], [ "Liu", "Bin", "" ] ]
TITLE: You are Who You Know and How You Behave: Attribute Inference Attacks via Users' Social Friends and Behaviors ABSTRACT: We propose new privacy attacks to infer attributes (e.g., locations, occupations, and interests) of online social network users. Our attacks leverage seemingly innocent user information that is publicly available in online social networks to infer missing attributes of targeted users. Given the increasing availability of (seemingly innocent) user information online, our results have serious implications for Internet privacy -- private attributes can be inferred from users' publicly available data unless we take steps to protect users from such inference attacks. To infer attributes of a targeted user, existing inference attacks leverage either the user's publicly available social friends or the user's behavioral records (e.g., the webpages that the user has liked on Facebook, the apps that the user has reviewed on Google Play), but not both. As we will show, such inference attacks achieve limited success rates. However, the problem becomes qualitatively different if we consider both social friends and behavioral records. To address this challenge, we develop a novel model to integrate social friends and behavioral records and design new attacks based on our model. We theoretically and experimentally demonstrate the effectiveness of our attacks. For instance, we observe that, in a real-world large-scale dataset with 1.1 million users, our attack can correctly infer the cities a user lived in for 57% of the users, via confidence estimation, we are able to increase the attack success rate to over 90% if the attacker selectively attacks a half of the users. Moreover, we show that our attack can correctly infer attributes for significantly more users than previous attacks.
no_new_dataset
0.942929
1606.05967
Amir Hossein Harati Nejad Torbati
Amir Hossein Harati Nejad Torbati, Joseph Picone
A Nonparametric Bayesian Approach for Spoken Term detection by Example Query
interspeech 2016
null
null
null
cs.CL
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
State of the art speech recognition systems use data-intensive context-dependent phonemes as acoustic units. However, these approaches do not translate well to low resourced languages where large amounts of training data is not available. For such languages, automatic discovery of acoustic units is critical. In this paper, we demonstrate the application of nonparametric Bayesian models to acoustic unit discovery. We show that the discovered units are correlated with phonemes and therefore are linguistically meaningful. We also present a spoken term detection (STD) by example query algorithm based on these automatically learned units. We show that our proposed system produces a P@N of 61.2% and an EER of 13.95% on the TIMIT dataset. The improvement in the EER is 5% while P@N is only slightly lower than the best reported system in the literature.
[ { "version": "v1", "created": "Mon, 20 Jun 2016 04:06:23 GMT" } ]
2016-06-21T00:00:00
[ [ "Torbati", "Amir Hossein Harati Nejad", "" ], [ "Picone", "Joseph", "" ] ]
TITLE: A Nonparametric Bayesian Approach for Spoken Term detection by Example Query ABSTRACT: State of the art speech recognition systems use data-intensive context-dependent phonemes as acoustic units. However, these approaches do not translate well to low resourced languages where large amounts of training data is not available. For such languages, automatic discovery of acoustic units is critical. In this paper, we demonstrate the application of nonparametric Bayesian models to acoustic unit discovery. We show that the discovered units are correlated with phonemes and therefore are linguistically meaningful. We also present a spoken term detection (STD) by example query algorithm based on these automatically learned units. We show that our proposed system produces a P@N of 61.2% and an EER of 13.95% on the TIMIT dataset. The improvement in the EER is 5% while P@N is only slightly lower than the best reported system in the literature.
no_new_dataset
0.953665
1606.06031
Sandro Pezzelle
Denis Paperno (1), Germ\'an Kruszewski (1), Angeliki Lazaridou (1), Quan Ngoc Pham (1), Raffaella Bernardi (1), Sandro Pezzelle (1), Marco Baroni (1), Gemma Boleda (1), Raquel Fern\'andez (2) ((1) CIMeC - Center for Mind/Brain Sciences, University of Trento, (2) Institute for Logic, Language & Computation, University of Amsterdam)
The LAMBADA dataset: Word prediction requiring a broad discourse context
10 pages, Accepted as a long paper for ACL 2016
null
null
null
cs.CL cs.AI cs.LG
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We introduce LAMBADA, a dataset to evaluate the capabilities of computational models for text understanding by means of a word prediction task. LAMBADA is a collection of narrative passages sharing the characteristic that human subjects are able to guess their last word if they are exposed to the whole passage, but not if they only see the last sentence preceding the target word. To succeed on LAMBADA, computational models cannot simply rely on local context, but must be able to keep track of information in the broader discourse. We show that LAMBADA exemplifies a wide range of linguistic phenomena, and that none of several state-of-the-art language models reaches accuracy above 1% on this novel benchmark. We thus propose LAMBADA as a challenging test set, meant to encourage the development of new models capable of genuine understanding of broad context in natural language text.
[ { "version": "v1", "created": "Mon, 20 Jun 2016 09:37:17 GMT" } ]
2016-06-21T00:00:00
[ [ "Paperno", "Denis", "" ], [ "Kruszewski", "Germán", "" ], [ "Lazaridou", "Angeliki", "" ], [ "Pham", "Quan Ngoc", "" ], [ "Bernardi", "Raffaella", "" ], [ "Pezzelle", "Sandro", "" ], [ "Baroni", "Marco", "" ], [ "Boleda", "Gemma", "" ], [ "Fernández", "Raquel", "" ] ]
TITLE: The LAMBADA dataset: Word prediction requiring a broad discourse context ABSTRACT: We introduce LAMBADA, a dataset to evaluate the capabilities of computational models for text understanding by means of a word prediction task. LAMBADA is a collection of narrative passages sharing the characteristic that human subjects are able to guess their last word if they are exposed to the whole passage, but not if they only see the last sentence preceding the target word. To succeed on LAMBADA, computational models cannot simply rely on local context, but must be able to keep track of information in the broader discourse. We show that LAMBADA exemplifies a wide range of linguistic phenomena, and that none of several state-of-the-art language models reaches accuracy above 1% on this novel benchmark. We thus propose LAMBADA as a challenging test set, meant to encourage the development of new models capable of genuine understanding of broad context in natural language text.
new_dataset
0.959383
1606.06121
Tolga Bolukbasi
Tolga Bolukbasi, Kai-Wei Chang, James Zou, Venkatesh Saligrama, Adam Kalai
Quantifying and Reducing Stereotypes in Word Embeddings
presented at 2016 ICML Workshop on #Data4Good: Machine Learning in Social Good Applications, New York, NY
null
null
null
cs.CL cs.LG stat.ML
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Machine learning algorithms are optimized to model statistical properties of the training data. If the input data reflects stereotypes and biases of the broader society, then the output of the learning algorithm also captures these stereotypes. In this paper, we initiate the study of gender stereotypes in {\em word embedding}, a popular framework to represent text data. As their use becomes increasingly common, applications can inadvertently amplify unwanted stereotypes. We show across multiple datasets that the embeddings contain significant gender stereotypes, especially with regard to professions. We created a novel gender analogy task and combined it with crowdsourcing to systematically quantify the gender bias in a given embedding. We developed an efficient algorithm that reduces gender stereotype using just a handful of training examples while preserving the useful geometric properties of the embedding. We evaluated our algorithm on several metrics. While we focus on male/female stereotypes, our framework may be applicable to other types of embedding biases.
[ { "version": "v1", "created": "Mon, 20 Jun 2016 13:58:45 GMT" } ]
2016-06-21T00:00:00
[ [ "Bolukbasi", "Tolga", "" ], [ "Chang", "Kai-Wei", "" ], [ "Zou", "James", "" ], [ "Saligrama", "Venkatesh", "" ], [ "Kalai", "Adam", "" ] ]
TITLE: Quantifying and Reducing Stereotypes in Word Embeddings ABSTRACT: Machine learning algorithms are optimized to model statistical properties of the training data. If the input data reflects stereotypes and biases of the broader society, then the output of the learning algorithm also captures these stereotypes. In this paper, we initiate the study of gender stereotypes in {\em word embedding}, a popular framework to represent text data. As their use becomes increasingly common, applications can inadvertently amplify unwanted stereotypes. We show across multiple datasets that the embeddings contain significant gender stereotypes, especially with regard to professions. We created a novel gender analogy task and combined it with crowdsourcing to systematically quantify the gender bias in a given embedding. We developed an efficient algorithm that reduces gender stereotype using just a handful of training examples while preserving the useful geometric properties of the embedding. We evaluated our algorithm on several metrics. While we focus on male/female stereotypes, our framework may be applicable to other types of embedding biases.
no_new_dataset
0.950088
1606.06258
Marco Crocco
Marco Crocco, Andrea Trucco, Alessio Del Bue
Uncalibrated 3D Room Reconstruction from Sound
The present work has been submitted to IEEE/ACM Transactions on Audio Speech and Language Processing
null
null
null
cs.SD
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
This paper presents a method to reconstruct the 3D structure of generic convex rooms from sound signals. Differently from most of the previous approaches, the method is fully uncalibrated in the sense that no knowledge about the microphones and sources position is needed. Moreover, we demonstrate that it is possible to bypass the well known echo labeling problem, allowing to reconstruct the room shape in a reasonable computation time without the need of additional hypotheses on the echoes order of arrival. Finally, the method is intrinsically robust to outliers and missing data in the echoes detection, allowing to work also in low SNR conditions. The proposed pipeline formalises the problem in different steps such as time of arrival estimation, microphones and sources localization and walls estimation. After providing a solution to these different problems we present a global optimization approach that links together all the problems in a single optimization function. The accuracy and robustness of the method is assessed on a wide set of simulated setups and in a challenging real scenario. Moreover we make freely available for a challenging dataset for 3D room reconstruction with accurate ground truth in a real scenario.
[ { "version": "v1", "created": "Mon, 20 Jun 2016 19:21:46 GMT" } ]
2016-06-21T00:00:00
[ [ "Crocco", "Marco", "" ], [ "Trucco", "Andrea", "" ], [ "Del Bue", "Alessio", "" ] ]
TITLE: Uncalibrated 3D Room Reconstruction from Sound ABSTRACT: This paper presents a method to reconstruct the 3D structure of generic convex rooms from sound signals. Differently from most of the previous approaches, the method is fully uncalibrated in the sense that no knowledge about the microphones and sources position is needed. Moreover, we demonstrate that it is possible to bypass the well known echo labeling problem, allowing to reconstruct the room shape in a reasonable computation time without the need of additional hypotheses on the echoes order of arrival. Finally, the method is intrinsically robust to outliers and missing data in the echoes detection, allowing to work also in low SNR conditions. The proposed pipeline formalises the problem in different steps such as time of arrival estimation, microphones and sources localization and walls estimation. After providing a solution to these different problems we present a global optimization approach that links together all the problems in a single optimization function. The accuracy and robustness of the method is assessed on a wide set of simulated setups and in a challenging real scenario. Moreover we make freely available for a challenging dataset for 3D room reconstruction with accurate ground truth in a real scenario.
no_new_dataset
0.949763
1512.06790
Siddharth Mahendran
Siddharth Mahendran and Ren\'e Vidal
Car Segmentation and Pose Estimation using 3D Object Models
null
null
null
null
cs.CV
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Image segmentation and 3D pose estimation are two key cogs in any algorithm for scene understanding. However, state-of-the-art CRF-based models for image segmentation rely mostly on 2D object models to construct top-down high-order potentials. In this paper, we propose new top-down potentials for image segmentation and pose estimation based on the shape and volume of a 3D object model. We show that these complex top-down potentials can be easily decomposed into standard forms for efficient inference in both the segmentation and pose estimation tasks. Experiments on a car dataset show that knowledge of segmentation helps perform pose estimation better and vice versa.
[ { "version": "v1", "created": "Mon, 21 Dec 2015 20:01:53 GMT" }, { "version": "v2", "created": "Fri, 17 Jun 2016 11:58:47 GMT" } ]
2016-06-20T00:00:00
[ [ "Mahendran", "Siddharth", "" ], [ "Vidal", "René", "" ] ]
TITLE: Car Segmentation and Pose Estimation using 3D Object Models ABSTRACT: Image segmentation and 3D pose estimation are two key cogs in any algorithm for scene understanding. However, state-of-the-art CRF-based models for image segmentation rely mostly on 2D object models to construct top-down high-order potentials. In this paper, we propose new top-down potentials for image segmentation and pose estimation based on the shape and volume of a 3D object model. We show that these complex top-down potentials can be easily decomposed into standard forms for efficient inference in both the segmentation and pose estimation tasks. Experiments on a car dataset show that knowledge of segmentation helps perform pose estimation better and vice versa.
no_new_dataset
0.949201
1605.04553
Dmitrijs Milajevs
Dmitrijs Milajevs and Sascha Griffiths
A Proposal for Linguistic Similarity Datasets Based on Commonality Lists
null
null
null
null
cs.CL
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Similarity is a core notion that is used in psychology and two branches of linguistics: theoretical and computational. The similarity datasets that come from the two fields differ in design: psychological datasets are focused around a certain topic such as fruit names, while linguistic datasets contain words from various categories. The later makes humans assign low similarity scores to the words that have nothing in common and to the words that have contrast in meaning, making similarity scores ambiguous. In this work we discuss the similarity collection procedure for a multi-category dataset that avoids score ambiguity and suggest changes to the evaluation procedure to reflect the insights of psychological literature for word, phrase and sentence similarity. We suggest to ask humans to provide a list of commonalities and differences instead of numerical similarity scores and employ the structure of human judgements beyond pairwise similarity for model evaluation. We believe that the proposed approach will give rise to datasets that test meaning representation models more thoroughly with respect to the human treatment of similarity.
[ { "version": "v1", "created": "Sun, 15 May 2016 14:00:06 GMT" }, { "version": "v2", "created": "Fri, 17 Jun 2016 16:55:20 GMT" } ]
2016-06-20T00:00:00
[ [ "Milajevs", "Dmitrijs", "" ], [ "Griffiths", "Sascha", "" ] ]
TITLE: A Proposal for Linguistic Similarity Datasets Based on Commonality Lists ABSTRACT: Similarity is a core notion that is used in psychology and two branches of linguistics: theoretical and computational. The similarity datasets that come from the two fields differ in design: psychological datasets are focused around a certain topic such as fruit names, while linguistic datasets contain words from various categories. The later makes humans assign low similarity scores to the words that have nothing in common and to the words that have contrast in meaning, making similarity scores ambiguous. In this work we discuss the similarity collection procedure for a multi-category dataset that avoids score ambiguity and suggest changes to the evaluation procedure to reflect the insights of psychological literature for word, phrase and sentence similarity. We suggest to ask humans to provide a list of commonalities and differences instead of numerical similarity scores and employ the structure of human judgements beyond pairwise similarity for model evaluation. We believe that the proposed approach will give rise to datasets that test meaning representation models more thoroughly with respect to the human treatment of similarity.
new_dataset
0.959345
1606.03556
Abhishek Das
Abhishek Das, Harsh Agrawal, C. Lawrence Zitnick, Devi Parikh, Dhruv Batra
Human Attention in Visual Question Answering: Do Humans and Deep Networks Look at the Same Regions?
9 pages, 6 figures, 3 tables; Under review at EMNLP 2016
null
null
null
cs.CV cs.CL
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We conduct large-scale studies on `human attention' in Visual Question Answering (VQA) to understand where humans choose to look to answer questions about images. We design and test multiple game-inspired novel attention-annotation interfaces that require the subject to sharpen regions of a blurred image to answer a question. Thus, we introduce the VQA-HAT (Human ATtention) dataset. We evaluate attention maps generated by state-of-the-art VQA models against human attention both qualitatively (via visualizations) and quantitatively (via rank-order correlation). Overall, our experiments show that current attention models in VQA do not seem to be looking at the same regions as humans.
[ { "version": "v1", "created": "Sat, 11 Jun 2016 05:41:10 GMT" }, { "version": "v2", "created": "Fri, 17 Jun 2016 04:39:01 GMT" } ]
2016-06-20T00:00:00
[ [ "Das", "Abhishek", "" ], [ "Agrawal", "Harsh", "" ], [ "Zitnick", "C. Lawrence", "" ], [ "Parikh", "Devi", "" ], [ "Batra", "Dhruv", "" ] ]
TITLE: Human Attention in Visual Question Answering: Do Humans and Deep Networks Look at the Same Regions? ABSTRACT: We conduct large-scale studies on `human attention' in Visual Question Answering (VQA) to understand where humans choose to look to answer questions about images. We design and test multiple game-inspired novel attention-annotation interfaces that require the subject to sharpen regions of a blurred image to answer a question. Thus, we introduce the VQA-HAT (Human ATtention) dataset. We evaluate attention maps generated by state-of-the-art VQA models against human attention both qualitatively (via visualizations) and quantitatively (via rank-order correlation). Overall, our experiments show that current attention models in VQA do not seem to be looking at the same regions as humans.
new_dataset
0.953708
1606.05374
Jacob Steinhardt
Jacob Steinhardt and Gregory Valiant and Moses Charikar
Avoiding Imposters and Delinquents: Adversarial Crowdsourcing and Peer Prediction
18 pages
null
null
null
cs.HC cs.CR cs.DS cs.GT cs.LG
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We consider a crowdsourcing model in which $n$ workers are asked to rate the quality of $n$ items previously generated by other workers. An unknown set of $\alpha n$ workers generate reliable ratings, while the remaining workers may behave arbitrarily and possibly adversarially. The manager of the experiment can also manually evaluate the quality of a small number of items, and wishes to curate together almost all of the high-quality items with at most an $\epsilon$ fraction of low-quality items. Perhaps surprisingly, we show that this is possible with an amount of work required of the manager, and each worker, that does not scale with $n$: the dataset can be curated with $\tilde{O}\Big(\frac{1}{\beta\alpha^3\epsilon^4}\Big)$ ratings per worker, and $\tilde{O}\Big(\frac{1}{\beta\epsilon^2}\Big)$ ratings by the manager, where $\beta$ is the fraction of high-quality items. Our results extend to the more general setting of peer prediction, including peer grading in online classrooms.
[ { "version": "v1", "created": "Thu, 16 Jun 2016 21:45:14 GMT" } ]
2016-06-20T00:00:00
[ [ "Steinhardt", "Jacob", "" ], [ "Valiant", "Gregory", "" ], [ "Charikar", "Moses", "" ] ]
TITLE: Avoiding Imposters and Delinquents: Adversarial Crowdsourcing and Peer Prediction ABSTRACT: We consider a crowdsourcing model in which $n$ workers are asked to rate the quality of $n$ items previously generated by other workers. An unknown set of $\alpha n$ workers generate reliable ratings, while the remaining workers may behave arbitrarily and possibly adversarially. The manager of the experiment can also manually evaluate the quality of a small number of items, and wishes to curate together almost all of the high-quality items with at most an $\epsilon$ fraction of low-quality items. Perhaps surprisingly, we show that this is possible with an amount of work required of the manager, and each worker, that does not scale with $n$: the dataset can be curated with $\tilde{O}\Big(\frac{1}{\beta\alpha^3\epsilon^4}\Big)$ ratings per worker, and $\tilde{O}\Big(\frac{1}{\beta\epsilon^2}\Big)$ ratings by the manager, where $\beta$ is the fraction of high-quality items. Our results extend to the more general setting of peer prediction, including peer grading in online classrooms.
no_new_dataset
0.940298
1606.05378
Reginald Long
Reginald Long, Panupong Pasupat, Percy Liang
Simpler Context-Dependent Logical Forms via Model Projections
10 pages, ACL 2016
null
null
null
cs.CL
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We consider the task of learning a context-dependent mapping from utterances to denotations. With only denotations at training time, we must search over a combinatorially large space of logical forms, which is even larger with context-dependent utterances. To cope with this challenge, we perform successive projections of the full model onto simpler models that operate over equivalence classes of logical forms. Though less expressive, we find that these simpler models are much faster and can be surprisingly effective. Moreover, they can be used to bootstrap the full model. Finally, we collected three new context-dependent semantic parsing datasets, and develop a new left-to-right parser.
[ { "version": "v1", "created": "Thu, 16 Jun 2016 21:57:11 GMT" } ]
2016-06-20T00:00:00
[ [ "Long", "Reginald", "" ], [ "Pasupat", "Panupong", "" ], [ "Liang", "Percy", "" ] ]
TITLE: Simpler Context-Dependent Logical Forms via Model Projections ABSTRACT: We consider the task of learning a context-dependent mapping from utterances to denotations. With only denotations at training time, we must search over a combinatorially large space of logical forms, which is even larger with context-dependent utterances. To cope with this challenge, we perform successive projections of the full model onto simpler models that operate over equivalence classes of logical forms. Though less expressive, we find that these simpler models are much faster and can be surprisingly effective. Moreover, they can be used to bootstrap the full model. Finally, we collected three new context-dependent semantic parsing datasets, and develop a new left-to-right parser.
new_dataset
0.952662
1606.05413
Chenchen Zhu
Chenchen Zhu, Yutong Zheng, Khoa Luu, Marios Savvides
CMS-RCNN: Contextual Multi-Scale Region-based CNN for Unconstrained Face Detection
null
null
null
null
cs.CV
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Robust face detection in the wild is one of the ultimate components to support various facial related problems, i.e. unconstrained face recognition, facial periocular recognition, facial landmarking and pose estimation, facial expression recognition, 3D facial model construction, etc. Although the face detection problem has been intensely studied for decades with various commercial applications, it still meets problems in some real-world scenarios due to numerous challenges, e.g. heavy facial occlusions, extremely low resolutions, strong illumination, exceptionally pose variations, image or video compression artifacts, etc. In this paper, we present a face detection approach named Contextual Multi-Scale Region-based Convolution Neural Network (CMS-RCNN) to robustly solve the problems mentioned above. Similar to the region-based CNNs, our proposed network consists of the region proposal component and the region-of-interest (RoI) detection component. However, far apart of that network, there are two main contributions in our proposed network that play a significant role to achieve the state-of-the-art performance in face detection. Firstly, the multi-scale information is grouped both in region proposal and RoI detection to deal with tiny face regions. Secondly, our proposed network allows explicit body contextual reasoning in the network inspired from the intuition of human vision system. The proposed approach is benchmarked on two recent challenging face detection databases, i.e. the WIDER FACE Dataset which contains high degree of variability, as well as the Face Detection Dataset and Benchmark (FDDB). The experimental results show that our proposed approach trained on WIDER FACE Dataset outperforms strong baselines on WIDER FACE Dataset by a large margin, and consistently achieves competitive results on FDDB against the recent state-of-the-art face detection methods.
[ { "version": "v1", "created": "Fri, 17 Jun 2016 03:19:09 GMT" } ]
2016-06-20T00:00:00
[ [ "Zhu", "Chenchen", "" ], [ "Zheng", "Yutong", "" ], [ "Luu", "Khoa", "" ], [ "Savvides", "Marios", "" ] ]
TITLE: CMS-RCNN: Contextual Multi-Scale Region-based CNN for Unconstrained Face Detection ABSTRACT: Robust face detection in the wild is one of the ultimate components to support various facial related problems, i.e. unconstrained face recognition, facial periocular recognition, facial landmarking and pose estimation, facial expression recognition, 3D facial model construction, etc. Although the face detection problem has been intensely studied for decades with various commercial applications, it still meets problems in some real-world scenarios due to numerous challenges, e.g. heavy facial occlusions, extremely low resolutions, strong illumination, exceptionally pose variations, image or video compression artifacts, etc. In this paper, we present a face detection approach named Contextual Multi-Scale Region-based Convolution Neural Network (CMS-RCNN) to robustly solve the problems mentioned above. Similar to the region-based CNNs, our proposed network consists of the region proposal component and the region-of-interest (RoI) detection component. However, far apart of that network, there are two main contributions in our proposed network that play a significant role to achieve the state-of-the-art performance in face detection. Firstly, the multi-scale information is grouped both in region proposal and RoI detection to deal with tiny face regions. Secondly, our proposed network allows explicit body contextual reasoning in the network inspired from the intuition of human vision system. The proposed approach is benchmarked on two recent challenging face detection databases, i.e. the WIDER FACE Dataset which contains high degree of variability, as well as the Face Detection Dataset and Benchmark (FDDB). The experimental results show that our proposed approach trained on WIDER FACE Dataset outperforms strong baselines on WIDER FACE Dataset by a large margin, and consistently achieves competitive results on FDDB against the recent state-of-the-art face detection methods.
no_new_dataset
0.945045
1606.05535
Qibin Zhao Dr
Qibin Zhao, Guoxu Zhou, Shengli Xie, Liqing Zhang, and Andrzej Cichocki
Tensor Ring Decomposition
null
null
null
null
cs.NA cs.CV cs.DS
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Tensor networks have in recent years emerged as the powerful tools for solving the large-scale optimization problems. One of the most popular tensor network is tensor train (TT) decomposition that acts as the building blocks for the complicated tensor networks. However, the TT decomposition highly depends on permutations of tensor dimensions, due to its strictly sequential multilinear products over latent cores, which leads to difficulties in finding the optimal TT representation. In this paper, we introduce a fundamental tensor decomposition model to represent a large dimensional tensor by a circular multilinear products over a sequence of low dimensional cores, which can be graphically interpreted as a cyclic interconnection of 3rd-order tensors, and thus termed as tensor ring (TR) decomposition. The key advantage of TR model is the circular dimensional permutation invariance which is gained by employing the trace operation and treating the latent cores equivalently. TR model can be viewed as a linear combination of TT decompositions, thus obtaining the powerful and generalized representation abilities. For optimization of latent cores, we present four different algorithms based on the sequential SVDs, ALS scheme, and block-wise ALS techniques. Furthermore, the mathematical properties of TR model are investigated, which shows that the basic multilinear algebra can be performed efficiently by using TR representaions and the classical tensor decompositions can be conveniently transformed into the TR representation. Finally, the experiments on both synthetic signals and real-world datasets were conducted to evaluate the performance of different algorithms.
[ { "version": "v1", "created": "Fri, 17 Jun 2016 14:40:18 GMT" } ]
2016-06-20T00:00:00
[ [ "Zhao", "Qibin", "" ], [ "Zhou", "Guoxu", "" ], [ "Xie", "Shengli", "" ], [ "Zhang", "Liqing", "" ], [ "Cichocki", "Andrzej", "" ] ]
TITLE: Tensor Ring Decomposition ABSTRACT: Tensor networks have in recent years emerged as the powerful tools for solving the large-scale optimization problems. One of the most popular tensor network is tensor train (TT) decomposition that acts as the building blocks for the complicated tensor networks. However, the TT decomposition highly depends on permutations of tensor dimensions, due to its strictly sequential multilinear products over latent cores, which leads to difficulties in finding the optimal TT representation. In this paper, we introduce a fundamental tensor decomposition model to represent a large dimensional tensor by a circular multilinear products over a sequence of low dimensional cores, which can be graphically interpreted as a cyclic interconnection of 3rd-order tensors, and thus termed as tensor ring (TR) decomposition. The key advantage of TR model is the circular dimensional permutation invariance which is gained by employing the trace operation and treating the latent cores equivalently. TR model can be viewed as a linear combination of TT decompositions, thus obtaining the powerful and generalized representation abilities. For optimization of latent cores, we present four different algorithms based on the sequential SVDs, ALS scheme, and block-wise ALS techniques. Furthermore, the mathematical properties of TR model are investigated, which shows that the basic multilinear algebra can be performed efficiently by using TR representaions and the classical tensor decompositions can be conveniently transformed into the TR representation. Finally, the experiments on both synthetic signals and real-world datasets were conducted to evaluate the performance of different algorithms.
no_new_dataset
0.949106
1606.05589
Abhishek Das
Abhishek Das, Harsh Agrawal, C. Lawrence Zitnick, Devi Parikh, Dhruv Batra
Human Attention in Visual Question Answering: Do Humans and Deep Networks Look at the Same Regions?
5 pages, 4 figures, 3 tables, presented at 2016 ICML Workshop on Human Interpretability in Machine Learning (WHI 2016), New York, NY. arXiv admin note: substantial text overlap with arXiv:1606.03556
null
null
null
stat.ML cs.CV
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We conduct large-scale studies on `human attention' in Visual Question Answering (VQA) to understand where humans choose to look to answer questions about images. We design and test multiple game-inspired novel attention-annotation interfaces that require the subject to sharpen regions of a blurred image to answer a question. Thus, we introduce the VQA-HAT (Human ATtention) dataset. We evaluate attention maps generated by state-of-the-art VQA models against human attention both qualitatively (via visualizations) and quantitatively (via rank-order correlation). Overall, our experiments show that current attention models in VQA do not seem to be looking at the same regions as humans.
[ { "version": "v1", "created": "Fri, 17 Jun 2016 17:00:02 GMT" } ]
2016-06-20T00:00:00
[ [ "Das", "Abhishek", "" ], [ "Agrawal", "Harsh", "" ], [ "Zitnick", "C. Lawrence", "" ], [ "Parikh", "Devi", "" ], [ "Batra", "Dhruv", "" ] ]
TITLE: Human Attention in Visual Question Answering: Do Humans and Deep Networks Look at the Same Regions? ABSTRACT: We conduct large-scale studies on `human attention' in Visual Question Answering (VQA) to understand where humans choose to look to answer questions about images. We design and test multiple game-inspired novel attention-annotation interfaces that require the subject to sharpen regions of a blurred image to answer a question. Thus, we introduce the VQA-HAT (Human ATtention) dataset. We evaluate attention maps generated by state-of-the-art VQA models against human attention both qualitatively (via visualizations) and quantitatively (via rank-order correlation). Overall, our experiments show that current attention models in VQA do not seem to be looking at the same regions as humans.
new_dataset
0.953708
1512.01655
Nicola Pezzotti
Nicola Pezzotti, Boudewijn P.F. Lelieveldt, Laurens van der Maaten, Thomas H\"ollt, Elmar Eisemann, and Anna Vilanova
Approximated and User Steerable tSNE for Progressive Visual Analytics
null
null
null
null
cs.CV cs.LG
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Progressive Visual Analytics aims at improving the interactivity in existing analytics techniques by means of visualization as well as interaction with intermediate results. One key method for data analysis is dimensionality reduction, for example, to produce 2D embeddings that can be visualized and analyzed efficiently. t-Distributed Stochastic Neighbor Embedding (tSNE) is a well-suited technique for the visualization of several high-dimensional data. tSNE can create meaningful intermediate results but suffers from a slow initialization that constrains its application in Progressive Visual Analytics. We introduce a controllable tSNE approximation (A-tSNE), which trades off speed and accuracy, to enable interactive data exploration. We offer real-time visualization techniques, including a density-based solution and a Magic Lens to inspect the degree of approximation. With this feedback, the user can decide on local refinements and steer the approximation level during the analysis. We demonstrate our technique with several datasets, in a real-world research scenario and for the real-time analysis of high-dimensional streams to illustrate its effectiveness for interactive data analysis.
[ { "version": "v1", "created": "Sat, 5 Dec 2015 12:05:52 GMT" }, { "version": "v2", "created": "Tue, 8 Dec 2015 14:56:25 GMT" }, { "version": "v3", "created": "Thu, 16 Jun 2016 09:36:40 GMT" } ]
2016-06-17T00:00:00
[ [ "Pezzotti", "Nicola", "" ], [ "Lelieveldt", "Boudewijn P. F.", "" ], [ "van der Maaten", "Laurens", "" ], [ "Höllt", "Thomas", "" ], [ "Eisemann", "Elmar", "" ], [ "Vilanova", "Anna", "" ] ]
TITLE: Approximated and User Steerable tSNE for Progressive Visual Analytics ABSTRACT: Progressive Visual Analytics aims at improving the interactivity in existing analytics techniques by means of visualization as well as interaction with intermediate results. One key method for data analysis is dimensionality reduction, for example, to produce 2D embeddings that can be visualized and analyzed efficiently. t-Distributed Stochastic Neighbor Embedding (tSNE) is a well-suited technique for the visualization of several high-dimensional data. tSNE can create meaningful intermediate results but suffers from a slow initialization that constrains its application in Progressive Visual Analytics. We introduce a controllable tSNE approximation (A-tSNE), which trades off speed and accuracy, to enable interactive data exploration. We offer real-time visualization techniques, including a density-based solution and a Magic Lens to inspect the degree of approximation. With this feedback, the user can decide on local refinements and steer the approximation level during the analysis. We demonstrate our technique with several datasets, in a real-world research scenario and for the real-time analysis of high-dimensional streams to illustrate its effectiveness for interactive data analysis.
no_new_dataset
0.944842
1602.05473
Lars Maal{\o}e
Lars Maal{\o}e, Casper Kaae S{\o}nderby, S{\o}ren Kaae S{\o}nderby, Ole Winther
Auxiliary Deep Generative Models
Proceedings of the 33rd International Conference on Machine Learning, New York, NY, USA, 2016, JMLR: Workshop and Conference Proceedings volume 48, Proceedings of the 33rd International Conference on Machine Learning, New York, NY, USA, 2016
null
null
null
stat.ML cs.AI cs.LG
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Deep generative models parameterized by neural networks have recently achieved state-of-the-art performance in unsupervised and semi-supervised learning. We extend deep generative models with auxiliary variables which improves the variational approximation. The auxiliary variables leave the generative model unchanged but make the variational distribution more expressive. Inspired by the structure of the auxiliary variable we also propose a model with two stochastic layers and skip connections. Our findings suggest that more expressive and properly specified deep generative models converge faster with better results. We show state-of-the-art performance within semi-supervised learning on MNIST, SVHN and NORB datasets.
[ { "version": "v1", "created": "Wed, 17 Feb 2016 16:24:50 GMT" }, { "version": "v2", "created": "Thu, 26 May 2016 10:21:34 GMT" }, { "version": "v3", "created": "Fri, 3 Jun 2016 09:19:21 GMT" }, { "version": "v4", "created": "Thu, 16 Jun 2016 06:39:08 GMT" } ]
2016-06-17T00:00:00
[ [ "Maaløe", "Lars", "" ], [ "Sønderby", "Casper Kaae", "" ], [ "Sønderby", "Søren Kaae", "" ], [ "Winther", "Ole", "" ] ]
TITLE: Auxiliary Deep Generative Models ABSTRACT: Deep generative models parameterized by neural networks have recently achieved state-of-the-art performance in unsupervised and semi-supervised learning. We extend deep generative models with auxiliary variables which improves the variational approximation. The auxiliary variables leave the generative model unchanged but make the variational distribution more expressive. Inspired by the structure of the auxiliary variable we also propose a model with two stochastic layers and skip connections. Our findings suggest that more expressive and properly specified deep generative models converge faster with better results. We show state-of-the-art performance within semi-supervised learning on MNIST, SVHN and NORB datasets.
no_new_dataset
0.947235
1606.04956
Ashton Anderson
Ashton Anderson, Jon Kleinberg and Sendhil Mullainathan
Assessing Human Error Against a Benchmark of Perfection
KDD 2016; 10 pages
null
10.1145/2939672.2939803
null
cs.AI cs.GT cs.SI
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
An increasing number of domains are providing us with detailed trace data on human decisions in settings where we can evaluate the quality of these decisions via an algorithm. Motivated by this development, an emerging line of work has begun to consider whether we can characterize and predict the kinds of decisions where people are likely to make errors. To investigate what a general framework for human error prediction might look like, we focus on a model system with a rich history in the behavioral sciences: the decisions made by chess players as they select moves in a game. We carry out our analysis at a large scale, employing datasets with several million recorded games, and using chess tablebases to acquire a form of ground truth for a subset of chess positions that have been completely solved by computers but remain challenging even for the best players in the world. We organize our analysis around three categories of features that we argue are present in most settings where the analysis of human error is applicable: the skill of the decision-maker, the time available to make the decision, and the inherent difficulty of the decision. We identify rich structure in all three of these categories of features, and find strong evidence that in our domain, features describing the inherent difficulty of an instance are significantly more powerful than features based on skill or time.
[ { "version": "v1", "created": "Wed, 15 Jun 2016 20:00:32 GMT" } ]
2016-06-17T00:00:00
[ [ "Anderson", "Ashton", "" ], [ "Kleinberg", "Jon", "" ], [ "Mullainathan", "Sendhil", "" ] ]
TITLE: Assessing Human Error Against a Benchmark of Perfection ABSTRACT: An increasing number of domains are providing us with detailed trace data on human decisions in settings where we can evaluate the quality of these decisions via an algorithm. Motivated by this development, an emerging line of work has begun to consider whether we can characterize and predict the kinds of decisions where people are likely to make errors. To investigate what a general framework for human error prediction might look like, we focus on a model system with a rich history in the behavioral sciences: the decisions made by chess players as they select moves in a game. We carry out our analysis at a large scale, employing datasets with several million recorded games, and using chess tablebases to acquire a form of ground truth for a subset of chess positions that have been completely solved by computers but remain challenging even for the best players in the world. We organize our analysis around three categories of features that we argue are present in most settings where the analysis of human error is applicable: the skill of the decision-maker, the time available to make the decision, and the inherent difficulty of the decision. We identify rich structure in all three of these categories of features, and find strong evidence that in our domain, features describing the inherent difficulty of an instance are significantly more powerful than features based on skill or time.
no_new_dataset
0.942612
1606.04985
Yanwei Cui
Yanwei Cui, Laetitia Chapel, S\'ebastien Lef\`evre
Combining multiscale features for classification of hyperspectral images: a sequence based kernel approach
8th IEEE GRSS Workshop on Hyperspectral Image and Signal Processing: Evolution in Remote Sensing (WHISPERS 2016), UCLA in Los Angeles, California, U.S
null
null
null
cs.CV cs.LG stat.ML
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Nowadays, hyperspectral image classification widely copes with spatial information to improve accuracy. One of the most popular way to integrate such information is to extract hierarchical features from a multiscale segmentation. In the classification context, the extracted features are commonly concatenated into a long vector (also called stacked vector), on which is applied a conventional vector-based machine learning technique (e.g. SVM with Gaussian kernel). In this paper, we rather propose to use a sequence structured kernel: the spectrum kernel. We show that the conventional stacked vector-based kernel is actually a special case of this kernel. Experiments conducted on various publicly available hyperspectral datasets illustrate the improvement of the proposed kernel w.r.t. conventional ones using the same hierarchical spatial features.
[ { "version": "v1", "created": "Wed, 15 Jun 2016 21:19:54 GMT" } ]
2016-06-17T00:00:00
[ [ "Cui", "Yanwei", "" ], [ "Chapel", "Laetitia", "" ], [ "Lefèvre", "Sébastien", "" ] ]
TITLE: Combining multiscale features for classification of hyperspectral images: a sequence based kernel approach ABSTRACT: Nowadays, hyperspectral image classification widely copes with spatial information to improve accuracy. One of the most popular way to integrate such information is to extract hierarchical features from a multiscale segmentation. In the classification context, the extracted features are commonly concatenated into a long vector (also called stacked vector), on which is applied a conventional vector-based machine learning technique (e.g. SVM with Gaussian kernel). In this paper, we rather propose to use a sequence structured kernel: the spectrum kernel. We show that the conventional stacked vector-based kernel is actually a special case of this kernel. Experiments conducted on various publicly available hyperspectral datasets illustrate the improvement of the proposed kernel w.r.t. conventional ones using the same hierarchical spatial features.
no_new_dataset
0.954009
1606.04991
Aryan Mokhtari
Aryan Mokhtari and Alec Koppel and Alejandro Ribeiro
A Class of Parallel Doubly Stochastic Algorithms for Large-Scale Learning
arXiv admin note: substantial text overlap with arXiv:1603.06782
null
null
null
cs.LG math.OC stat.ML
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We consider learning problems over training sets in which both, the number of training examples and the dimension of the feature vectors, are large. To solve these problems we propose the random parallel stochastic algorithm (RAPSA). We call the algorithm random parallel because it utilizes multiple parallel processors to operate on a randomly chosen subset of blocks of the feature vector. We call the algorithm stochastic because processors choose training subsets uniformly at random. Algorithms that are parallel in either of these dimensions exist, but RAPSA is the first attempt at a methodology that is parallel in both the selection of blocks and the selection of elements of the training set. In RAPSA, processors utilize the randomly chosen functions to compute the stochastic gradient component associated with a randomly chosen block. The technical contribution of this paper is to show that this minimally coordinated algorithm converges to the optimal classifier when the training objective is convex. Moreover, we present an accelerated version of RAPSA (ARAPSA) that incorporates the objective function curvature information by premultiplying the descent direction by a Hessian approximation matrix. We further extend the results for asynchronous settings and show that if the processors perform their updates without any coordination the algorithms are still convergent to the optimal argument. RAPSA and its extensions are then numerically evaluated on a linear estimation problem and a binary image classification task using the MNIST handwritten digit dataset.
[ { "version": "v1", "created": "Wed, 15 Jun 2016 21:34:46 GMT" } ]
2016-06-17T00:00:00
[ [ "Mokhtari", "Aryan", "" ], [ "Koppel", "Alec", "" ], [ "Ribeiro", "Alejandro", "" ] ]
TITLE: A Class of Parallel Doubly Stochastic Algorithms for Large-Scale Learning ABSTRACT: We consider learning problems over training sets in which both, the number of training examples and the dimension of the feature vectors, are large. To solve these problems we propose the random parallel stochastic algorithm (RAPSA). We call the algorithm random parallel because it utilizes multiple parallel processors to operate on a randomly chosen subset of blocks of the feature vector. We call the algorithm stochastic because processors choose training subsets uniformly at random. Algorithms that are parallel in either of these dimensions exist, but RAPSA is the first attempt at a methodology that is parallel in both the selection of blocks and the selection of elements of the training set. In RAPSA, processors utilize the randomly chosen functions to compute the stochastic gradient component associated with a randomly chosen block. The technical contribution of this paper is to show that this minimally coordinated algorithm converges to the optimal classifier when the training objective is convex. Moreover, we present an accelerated version of RAPSA (ARAPSA) that incorporates the objective function curvature information by premultiplying the descent direction by a Hessian approximation matrix. We further extend the results for asynchronous settings and show that if the processors perform their updates without any coordination the algorithms are still convergent to the optimal argument. RAPSA and its extensions are then numerically evaluated on a linear estimation problem and a binary image classification task using the MNIST handwritten digit dataset.
no_new_dataset
0.944995
1606.05007
Naoya Takahashi
Naoya Takahashi, Tofigh Naghibi, Beat Pfister
Automatic Pronunciation Generation by Utilizing a Semi-supervised Deep Neural Networks
Proc. of 17th Interspeech (2016), San Francisco, California, USA
null
null
null
cs.CL cs.LG cs.SD
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Phonemic or phonetic sub-word units are the most commonly used atomic elements to represent speech signals in modern ASRs. However they are not the optimal choice due to several reasons such as: large amount of effort required to handcraft a pronunciation dictionary, pronunciation variations, human mistakes and under-resourced dialects and languages. Here, we propose a data-driven pronunciation estimation and acoustic modeling method which only takes the orthographic transcription to jointly estimate a set of sub-word units and a reliable dictionary. Experimental results show that the proposed method which is based on semi-supervised training of a deep neural network largely outperforms phoneme based continuous speech recognition on the TIMIT dataset.
[ { "version": "v1", "created": "Wed, 15 Jun 2016 23:45:33 GMT" } ]
2016-06-17T00:00:00
[ [ "Takahashi", "Naoya", "" ], [ "Naghibi", "Tofigh", "" ], [ "Pfister", "Beat", "" ] ]
TITLE: Automatic Pronunciation Generation by Utilizing a Semi-supervised Deep Neural Networks ABSTRACT: Phonemic or phonetic sub-word units are the most commonly used atomic elements to represent speech signals in modern ASRs. However they are not the optimal choice due to several reasons such as: large amount of effort required to handcraft a pronunciation dictionary, pronunciation variations, human mistakes and under-resourced dialects and languages. Here, we propose a data-driven pronunciation estimation and acoustic modeling method which only takes the orthographic transcription to jointly estimate a set of sub-word units and a reliable dictionary. Experimental results show that the proposed method which is based on semi-supervised training of a deep neural network largely outperforms phoneme based continuous speech recognition on the TIMIT dataset.
no_new_dataset
0.950778
1606.05032
Yang Yang
Yang Yang, Weilun Chen, Yadan Luo, Fumin Shen, Jie Shao and Heng Tao Shen
Zero-Shot Hashing via Transferring Supervised Knowledge
11 pages
null
null
null
cs.CV
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Hashing has shown its efficiency and effectiveness in facilitating large-scale multimedia applications. Supervised knowledge e.g. semantic labels or pair-wise relationship) associated to data is capable of significantly improving the quality of hash codes and hash functions. However, confronted with the rapid growth of newly-emerging concepts and multimedia data on the Web, existing supervised hashing approaches may easily suffer from the scarcity and validity of supervised information due to the expensive cost of manual labelling. In this paper, we propose a novel hashing scheme, termed \emph{zero-shot hashing} (ZSH), which compresses images of "unseen" categories to binary codes with hash functions learned from limited training data of "seen" categories. Specifically, we project independent data labels i.e. 0/1-form label vectors) into semantic embedding space, where semantic relationships among all the labels can be precisely characterized and thus seen supervised knowledge can be transferred to unseen classes. Moreover, in order to cope with the semantic shift problem, we rotate the embedded space to more suitably align the embedded semantics with the low-level visual feature space, thereby alleviating the influence of semantic gap. In the meantime, to exert positive effects on learning high-quality hash functions, we further propose to preserve local structural property and discrete nature in binary codes. Besides, we develop an efficient alternating algorithm to solve the ZSH model. Extensive experiments conducted on various real-life datasets show the superior zero-shot image retrieval performance of ZSH as compared to several state-of-the-art hashing methods.
[ { "version": "v1", "created": "Thu, 16 Jun 2016 02:56:39 GMT" } ]
2016-06-17T00:00:00
[ [ "Yang", "Yang", "" ], [ "Chen", "Weilun", "" ], [ "Luo", "Yadan", "" ], [ "Shen", "Fumin", "" ], [ "Shao", "Jie", "" ], [ "Shen", "Heng Tao", "" ] ]
TITLE: Zero-Shot Hashing via Transferring Supervised Knowledge ABSTRACT: Hashing has shown its efficiency and effectiveness in facilitating large-scale multimedia applications. Supervised knowledge e.g. semantic labels or pair-wise relationship) associated to data is capable of significantly improving the quality of hash codes and hash functions. However, confronted with the rapid growth of newly-emerging concepts and multimedia data on the Web, existing supervised hashing approaches may easily suffer from the scarcity and validity of supervised information due to the expensive cost of manual labelling. In this paper, we propose a novel hashing scheme, termed \emph{zero-shot hashing} (ZSH), which compresses images of "unseen" categories to binary codes with hash functions learned from limited training data of "seen" categories. Specifically, we project independent data labels i.e. 0/1-form label vectors) into semantic embedding space, where semantic relationships among all the labels can be precisely characterized and thus seen supervised knowledge can be transferred to unseen classes. Moreover, in order to cope with the semantic shift problem, we rotate the embedded space to more suitably align the embedded semantics with the low-level visual feature space, thereby alleviating the influence of semantic gap. In the meantime, to exert positive effects on learning high-quality hash functions, we further propose to preserve local structural property and discrete nature in binary codes. Besides, we develop an efficient alternating algorithm to solve the ZSH model. Extensive experiments conducted on various real-life datasets show the superior zero-shot image retrieval performance of ZSH as compared to several state-of-the-art hashing methods.
no_new_dataset
0.948775
1606.05060
Feng Nan
Feng Nan, Joseph Wang, Venkatesh Saligrama
Pruning Random Forests for Prediction on a Budget
null
null
null
null
stat.ML cs.LG
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We propose to prune a random forest (RF) for resource-constrained prediction. We first construct a RF and then prune it to optimize expected feature cost & accuracy. We pose pruning RFs as a novel 0-1 integer program with linear constraints that encourages feature re-use. We establish total unimodularity of the constraint set to prove that the corresponding LP relaxation solves the original integer program. We then exploit connections to combinatorial optimization and develop an efficient primal-dual algorithm, scalable to large datasets. In contrast to our bottom-up approach, which benefits from good RF initialization, conventional methods are top-down acquiring features based on their utility value and is generally intractable, requiring heuristics. Empirically, our pruning algorithm outperforms existing state-of-the-art resource-constrained algorithms.
[ { "version": "v1", "created": "Thu, 16 Jun 2016 05:56:36 GMT" } ]
2016-06-17T00:00:00
[ [ "Nan", "Feng", "" ], [ "Wang", "Joseph", "" ], [ "Saligrama", "Venkatesh", "" ] ]
TITLE: Pruning Random Forests for Prediction on a Budget ABSTRACT: We propose to prune a random forest (RF) for resource-constrained prediction. We first construct a RF and then prune it to optimize expected feature cost & accuracy. We pose pruning RFs as a novel 0-1 integer program with linear constraints that encourages feature re-use. We establish total unimodularity of the constraint set to prove that the corresponding LP relaxation solves the original integer program. We then exploit connections to combinatorial optimization and develop an efficient primal-dual algorithm, scalable to large datasets. In contrast to our bottom-up approach, which benefits from good RF initialization, conventional methods are top-down acquiring features based on their utility value and is generally intractable, requiring heuristics. Empirically, our pruning algorithm outperforms existing state-of-the-art resource-constrained algorithms.
no_new_dataset
0.948822
1606.05242
Pedro Saleiro
Pedro Saleiro, Lu\'is Gomes, Carlos Soares
Sentiment Aggregate Functions for Political Opinion Polling using Microblog Streams
null
null
null
null
cs.SI
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The automatic content analysis of mass media in the social sciences has become necessary and possible with the raise of social media and computational power. One particularly promising avenue of research concerns the use of sentiment analysis in microblog streams. However, one of the main challenges consists in aggregating sentiment polarity in a timely fashion that can be fed to the prediction method. We investigated a large set of sentiment aggregate functions and performed a regression analysis using political opinion polls as gold standard. Our dataset contains nearly 233 000 tweets, classified according to their polarity (positive, negative or neutral), regarding the five main Portuguese political leaders during the Portuguese bailout (2011-2014). Results show that different sentiment aggregate functions exhibit different feature importance over time while the error keeps almost unchanged.
[ { "version": "v1", "created": "Thu, 16 Jun 2016 16:14:58 GMT" } ]
2016-06-17T00:00:00
[ [ "Saleiro", "Pedro", "" ], [ "Gomes", "Luís", "" ], [ "Soares", "Carlos", "" ] ]
TITLE: Sentiment Aggregate Functions for Political Opinion Polling using Microblog Streams ABSTRACT: The automatic content analysis of mass media in the social sciences has become necessary and possible with the raise of social media and computational power. One particularly promising avenue of research concerns the use of sentiment analysis in microblog streams. However, one of the main challenges consists in aggregating sentiment polarity in a timely fashion that can be fed to the prediction method. We investigated a large set of sentiment aggregate functions and performed a regression analysis using political opinion polls as gold standard. Our dataset contains nearly 233 000 tweets, classified according to their polarity (positive, negative or neutral), regarding the five main Portuguese political leaders during the Portuguese bailout (2011-2014). Results show that different sentiment aggregate functions exhibit different feature importance over time while the error keeps almost unchanged.
new_dataset
0.959837