January 24, 2020

2724 words 13 mins read

Paper Group NANR 230

Paper Group NANR 230

Differentially Private Bagging: Improved utility and cheaper privacy than subsample-and-aggregate. Identification of Adverse Drug Reaction Mentions in Tweets – SMM4H Shared Task 2019. ltl.uni-due at SemEval-2019 Task 5: Simple but Effective Lexico-Semantic Features for Detecting Hate Speech in Twitter. A Personalized Sentiment Model with Textual a …

Differentially Private Bagging: Improved utility and cheaper privacy than subsample-and-aggregate

Title Differentially Private Bagging: Improved utility and cheaper privacy than subsample-and-aggregate
Authors James Jordon, Jinsung Yoon, Mihaela Van Der Schaar
Abstract Differential Privacy is a popular and well-studied notion of privacy. In the era ofbig data that we are in, privacy concerns are becoming ever more prevalent and thusdifferential privacy is being turned to as one such solution. A popular method forensuring differential privacy of a classifier is known as subsample-and-aggregate,in which the dataset is divided into distinct chunks and a model is learned on eachchunk, after which it is aggregated. This approach allows for easy analysis of themodel on the data and thus differential privacy can be easily applied. In this paper,we extend this approach by dividing the data several times (rather than just once)and learning models on each chunk within each division. The first benefit of thisapproach is the natural improvement of utility by aggregating models trained ona more diverse range of subsets of the data (as demonstrated by the well-knownbagging technique). The second benefit is that, through analysis that we provide inthe paper, we can derive tighter differential privacy guarantees when several queriesare made to this mechanism. In order to derive these guarantees, we introducethe upwards and downwards moments accountants and derive bounds for thesemoments accountants in a data-driven fashion. We demonstrate the improvementsour model makes over standard subsample-and-aggregate in two datasets (HeartFailure (private) and UCI Adult (public)).
Tasks
Published 2019-12-01
URL http://papers.nips.cc/paper/8684-differentially-private-bagging-improved-utility-and-cheaper-privacy-than-subsample-and-aggregate
PDF http://papers.nips.cc/paper/8684-differentially-private-bagging-improved-utility-and-cheaper-privacy-than-subsample-and-aggregate.pdf
PWC https://paperswithcode.com/paper/differentially-private-bagging-improved
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Identification of Adverse Drug Reaction Mentions in Tweets – SMM4H Shared Task 2019

Title Identification of Adverse Drug Reaction Mentions in Tweets – SMM4H Shared Task 2019
Authors Samarth Rawal, Siddharth Rawal, Saadat Anwar, Chitta Baral
Abstract Analyzing social media posts can offer insights into a wide range of topics that are commonly discussed online, providing valuable information for studying various health-related phenomena reported online. The outcome of this work can offer insights into pharmacovigilance research to monitor the adverse effects of medications. This research specifically looks into mentions of adverse drug reactions (ADRs) in Twitter data through the Social Media Mining for Health Applications (SMM4H) Shared Task 2019. Adverse drug reactions are undesired harmful effects which can arise from medication or other methods of treatment. The goal of this research is to build accurate models using natural language processing techniques to detect reports of adverse drug reactions in Twitter data and extract these words or phrases.
Tasks
Published 2019-08-01
URL https://www.aclweb.org/anthology/W19-3225/
PDF https://www.aclweb.org/anthology/W19-3225
PWC https://paperswithcode.com/paper/identification-of-adverse-drug-reaction
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ltl.uni-due at SemEval-2019 Task 5: Simple but Effective Lexico-Semantic Features for Detecting Hate Speech in Twitter

Title ltl.uni-due at SemEval-2019 Task 5: Simple but Effective Lexico-Semantic Features for Detecting Hate Speech in Twitter
Authors Huangpan Zhang, Michael Wojatzki, Tobias Horsmann, Torsten Zesch
Abstract In this paper, we present our contribution to SemEval 2019 Task 5 Multilingual Detection of Hate, specifically in the Subtask A (English and Spanish). We compare different configurations of shallow and deep learning approaches on the English data and use the system that performs best in both sub-tasks. The resulting SVM-based system with lexicosemantic features (n-grams and embeddings) is ranked 23rd out of 69 on the English data and beats the baseline system. On the Spanish data our system is ranked 25th out of 39.
Tasks
Published 2019-06-01
URL https://www.aclweb.org/anthology/S19-2078/
PDF https://www.aclweb.org/anthology/S19-2078
PWC https://paperswithcode.com/paper/ltluni-due-at-semeval-2019-task-5-simple-but
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A Personalized Sentiment Model with Textual and Contextual Information

Title A Personalized Sentiment Model with Textual and Contextual Information
Authors Siwen Guo, Sviatlana H{"o}hn, Christoph Schommer
Abstract In this paper, we look beyond the traditional population-level sentiment modeling and consider the individuality in a person{'}s expressions by discovering both textual and contextual information. In particular, we construct a hierarchical neural network that leverages valuable information from a person{'}s past expressions, and offer a better understanding of the sentiment from the expresser{'}s perspective. Additionally, we investigate how a person{'}s sentiment changes over time so that recent incidents or opinions may have more effect on the person{'}s current sentiment than the old ones. Psychological studies have also shown that individual variation exists in how easily people change their sentiments. In order to model such traits, we develop a modified attention mechanism with Hawkes process applied on top of a recurrent network for a user-specific design. Implemented with automatically labeled Twitter data, the proposed model has shown positive results employing different input formulations for representing the concerned information.
Tasks
Published 2019-11-01
URL https://www.aclweb.org/anthology/K19-1093/
PDF https://www.aclweb.org/anthology/K19-1093
PWC https://paperswithcode.com/paper/a-personalized-sentiment-model-with-textual
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Spelling-Aware Construction of Macaronic Texts for Teaching Foreign-Language Vocabulary

Title Spelling-Aware Construction of Macaronic Texts for Teaching Foreign-Language Vocabulary
Authors Adithya Renduchintala, Philipp Koehn, Jason Eisner
Abstract We present a machine foreign-language teacher that modifies text in a student{'}s native language (L1) by replacing some word tokens with glosses in a foreign language (L2), in such a way that the student can acquire L2 vocabulary simply by reading the resulting macaronic text. The machine teacher uses no supervised data from human students. Instead, to guide the machine teacher{'}s choice of which words to replace, we equip a cloze language model with a training procedure that can incrementally learn representations for novel words, and use this model as a proxy for the word guessing and learning ability of real human students. We use Mechanical Turk to evaluate two variants of the student model: (i) one that generates a representation for a novel word using only surrounding context and (ii) an extension that also uses the spelling of the novel word.
Tasks Language Modelling
Published 2019-11-01
URL https://www.aclweb.org/anthology/D19-1679/
PDF https://www.aclweb.org/anthology/D19-1679
PWC https://paperswithcode.com/paper/spelling-aware-construction-of-macaronic
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Almost Horizon-Free Structure-Aware Best Policy Identification with a Generative Model

Title Almost Horizon-Free Structure-Aware Best Policy Identification with a Generative Model
Authors Andrea Zanette, Mykel J. Kochenderfer, Emma Brunskill
Abstract This paper focuses on the problem of computing an $\epsilon$-optimal policy in a discounted Markov Decision Process (MDP) provided that we can access the reward and transition function through a generative model. We propose an algorithm that is initially agnostic to the MDP but that can leverage the specific MDP structure, expressed in terms of variances of the rewards and next-state value function, and gaps in the optimal action-value function to reduce the sample complexity needed to find a good policy, precisely highlighting the contribution of each state-action pair to the final sample complexity. A key feature of our analysis is that it removes all horizon dependencies in the sample complexity of suboptimal actions except for the intrinsic scaling of the value function and a constant additive term.
Tasks
Published 2019-12-01
URL http://papers.nips.cc/paper/8800-almost-horizon-free-structure-aware-best-policy-identification-with-a-generative-model
PDF http://papers.nips.cc/paper/8800-almost-horizon-free-structure-aware-best-policy-identification-with-a-generative-model.pdf
PWC https://paperswithcode.com/paper/almost-horizon-free-structure-aware-best
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YNU NLP at SemEval-2019 Task 5: Attention and Capsule Ensemble for Identifying Hate Speech

Title YNU NLP at SemEval-2019 Task 5: Attention and Capsule Ensemble for Identifying Hate Speech
Authors Bin Wang, Haiyan Ding
Abstract This paper describes the system submitted to SemEval 2019 Task 5: Multilingual detection of hate speech against immigrants and women in Twitter (hatEval). Its main purpose is to conduct hate speech detection on Twitter, which mainly includes two specific different targets, immigrants and women. We participate in both subtask A and subtask B for English. In order to address this task, we develope an ensemble of an attention-LSTM model based on HAN and an BiGRU-capsule model. Both models use fastText pre-trained embeddings, and we use this model in both subtasks. In comparison to other participating teams, our system is ranked 16th in the Sub-task A for English, and 12th in the Sub-task B for English.
Tasks Hate Speech Detection
Published 2019-06-01
URL https://www.aclweb.org/anthology/S19-2095/
PDF https://www.aclweb.org/anthology/S19-2095
PWC https://paperswithcode.com/paper/ynu-nlp-at-semeval-2019-task-5-attention-and
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Controlling the Specificity of Clarification Question Generation

Title Controlling the Specificity of Clarification Question Generation
Authors Yang Trista Cao, Sudha Rao, Hal Daum{'e} III
Abstract Unlike comprehension-style questions, clarification questions look for some missing information in a given context. However, without guidance, neural models for question generation, similar to dialog generation models, lead to generic and bland questions that cannot elicit useful information. We argue that controlling the level of specificity of the generated questions can have useful applications and propose a neural clarification question generation model for the same. We first train a classifier that annotates a clarification question with its level of specificity (generic or specific) to the given context. Our results on the Amazon questions dataset demonstrate that training a clarification question generation model on specificity annotated data can generate questions with varied levels of specificity to the given context.
Tasks Question Generation
Published 2019-08-01
URL https://www.aclweb.org/anthology/papers/W/W19/W19-3619/
PDF https://www.aclweb.org/anthology/W19-3619
PWC https://paperswithcode.com/paper/controlling-the-specificity-of-clarification
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SILCO: Show a Few Images, Localize the Common Object

Title SILCO: Show a Few Images, Localize the Common Object
Authors Tao Hu, Pascal Mettes, Jia-Hong Huang, Cees G. M. Snoek
Abstract Few-shot learning is a nascent research topic, motivated by the fact that traditional deep learning requires tremendous amounts of data. In this work, we propose a new task along this research direction, we call few-shot common-localization. Given a few weakly-supervised support images, we aim to localize the common object in the query image without any box annotation. This task differs from standard few-shot settings, since we aim to address the localization problem, rather than the global classification problem. To tackle this new problem, we propose a network that aims to get the most out of the support and query images. To that end, we introduce a spatial similarity module that searches the spatial commonality among the given images. We furthermore introduce a feature reweighting module to balance the influence of different support images through graph convolutional networks. To evaluate few-shot common-localization, we repurpose and reorganize the well-known Pascal VOC and MS-COCO datasets, as well as a video dataset from ImageNet VID. Experiments on the new settings for few-shot common-localization shows the importance of searching for spatial similarity and feature reweighting, outperforming baselines from related tasks.
Tasks Few-Shot Learning
Published 2019-10-01
URL http://openaccess.thecvf.com/content_ICCV_2019/html/Hu_SILCO_Show_a_Few_Images_Localize_the_Common_Object_ICCV_2019_paper.html
PDF http://openaccess.thecvf.com/content_ICCV_2019/papers/Hu_SILCO_Show_a_Few_Images_Localize_the_Common_Object_ICCV_2019_paper.pdf
PWC https://paperswithcode.com/paper/silco-show-a-few-images-localize-the-common
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The ERG at MRP 2019: Radically Compositional Semantic Dependencies

Title The ERG at MRP 2019: Radically Compositional Semantic Dependencies
Authors Stephan Oepen, Dan Flickinger
Abstract The English Resource Grammar (ERG) is a broad-coverage computational grammar of English that outputs underspecified logical-form representations of meaning in a framework dubbed English Resource Semantics (ERS). Two of the target representations in the the 2019 Shared Task on Cross-Framework Meaning Representation Parsing (MRP 2019) derive graph-based simplifications of ERS, viz. Elementary Dependency Structures (EDS) and DELPH-IN MRS Bi-Lexical Dependencies (DM). As a point of reference outside the official MRP competition, we parsed the evaluation strings using the ERG and converted the resulting meaning representations to EDS and DM. These graphs yield higher evaluation scores than the purely data-driven parsers in the actual shared task, suggesting that the general-purpose linguistic knowledge about English grammar encoded in the ERG can add value when parsing into these meaning representations.
Tasks
Published 2019-11-01
URL https://www.aclweb.org/anthology/K19-2003/
PDF https://www.aclweb.org/anthology/K19-2003
PWC https://paperswithcode.com/paper/the-erg-at-mrp-2019-radically-compositional
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ShanghaiTech at MRP 2019: Sequence-to-Graph Transduction with Second-Order Edge Inference for Cross-Framework Meaning Representation Parsing

Title ShanghaiTech at MRP 2019: Sequence-to-Graph Transduction with Second-Order Edge Inference for Cross-Framework Meaning Representation Parsing
Authors Xinyu Wang, Yixian Liu, Zixia Jia, Chengyue Jiang, Kewei Tu
Abstract This paper presents the system used in our submission to the CoNLL 2019 shared task: Cross-Framework Meaning Representation Parsing. Our system is a graph-based parser which combines an extended pointer-generator network that generates nodes and a second-order mean field variational inference module that predicts edges. Our system achieved 1st and 2nd place for the DM and PSD frameworks respectively on the in-framework ranks and achieved 3rd place for the DM framework on the cross-framework ranks.
Tasks
Published 2019-11-01
URL https://www.aclweb.org/anthology/K19-2005/
PDF https://www.aclweb.org/anthology/K19-2005
PWC https://paperswithcode.com/paper/shanghaitech-at-mrp-2019-sequence-to-graph
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Title A Primal-Dual link between GANs and Autoencoders
Authors Hisham Husain, Richard Nock, Robert C. Williamson
Abstract Since the introduction of Generative Adversarial Networks (GANs) and Variational Autoencoders (VAE), the literature on generative modelling has witnessed an overwhelming resurgence. The impressive, yet elusive empirical performance of GANs has lead to the rise of many GAN-VAE hybrids, with the hopes of GAN level performance and additional benefits of VAE, such as an encoder for feature reduction, which is not offered by GANs. Recently, the Wasserstein Autoencoder (WAE) was proposed, achieving performance similar to that of GANs, yet it is still unclear whether the two are fundamentally different or can be further improved into a unified model. In this work, we study the $f$-GAN and WAE models and make two main discoveries. First, we find that the $f$-GAN and WAE objectives partake in a primal-dual relationship and are equivalent under some assumptions, which then allows us to explicate the success of WAE. Second, the equivalence result allows us to, for the first time, prove generalization bounds for Autoencoder models, which is a pertinent problem when it comes to theoretical analyses of generative models. Furthermore, we show that the WAE objective is related to other statistical quantities such as the $f$-divergence and in particular, upper bounded by the Wasserstein distance, which then allows us to tap into existing efficient (regularized) optimal transport solvers. Our findings thus present the first primal-dual relationship between GANs and Autoencoder models, comment on generalization abilities and make a step towards unifying these models.
Tasks
Published 2019-12-01
URL http://papers.nips.cc/paper/8333-a-primal-dual-link-between-gans-and-autoencoders
PDF http://papers.nips.cc/paper/8333-a-primal-dual-link-between-gans-and-autoencoders.pdf
PWC https://paperswithcode.com/paper/a-primal-dual-link-between-gans-and
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Learning to Ask for Conversational Machine Learning

Title Learning to Ask for Conversational Machine Learning
Authors Shashank Srivastava, Igor Labutov, Tom Mitchell
Abstract Natural language has recently been explored as a new medium of supervision for training machine learning models. Here, we explore learning classification tasks using language in a conversational setting {–} where the automated learner does not simply receive language input from a teacher, but can proactively engage the teacher by asking questions. We present a reinforcement learning framework, where the learner{'}s actions correspond to question types and the reward for asking a question is based on how the teacher{'}s response changes performance of the resulting machine learning model on the learning task. In this framework, learning good question-asking strategies corresponds to asking sequences of questions that maximize the cumulative (discounted) reward, and hence quickly lead to effective classifiers. Empirical analysis across three domains shows that learned question-asking strategies expedite classifier training by asking appropriate questions at different points in the learning process. The approach allows learning classifiers from a blend of strategies, including learning from observations, explanations and clarifications.
Tasks
Published 2019-11-01
URL https://www.aclweb.org/anthology/D19-1426/
PDF https://www.aclweb.org/anthology/D19-1426
PWC https://paperswithcode.com/paper/learning-to-ask-for-conversational-machine
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Low-Rank Approximations of Second-Order Document Representations

Title Low-Rank Approximations of Second-Order Document Representations
Authors Jarkko Lagus, Janne Sinkkonen, Arto Klami
Abstract Document embeddings, created with methods ranging from simple heuristics to statistical and deep models, are widely applicable. Bag-of-vectors models for documents include the mean and quadratic approaches (Torki, 2018). We present evidence that quadratic statistics alone, without the mean information, can offer superior accuracy, fast document comparison, and compact document representations. In matching news articles to their comment threads, low-rank representations of only 3-4 times the size of the mean vector give most accurate matching, and in standard sentence comparison tasks, results are state of the art despite faster computation. Similarity measures are discussed, and the Frobenius product implicit in the proposed method is contrasted to Wasserstein or Bures metric from the transportation theory. We also shortly demonstrate matching of unordered word lists to documents, to measure topicality or sentiment of documents.
Tasks
Published 2019-11-01
URL https://www.aclweb.org/anthology/K19-1059/
PDF https://www.aclweb.org/anthology/K19-1059
PWC https://paperswithcode.com/paper/low-rank-approximations-of-second-order
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GenSMT at SemEval-2019 Task 3: Contextual Emotion Detection in tweets using multi task generic approach

Title GenSMT at SemEval-2019 Task 3: Contextual Emotion Detection in tweets using multi task generic approach
Authors Dumitru Bogdan
Abstract In this paper, we describe our participation in SemEval-2019 Task 3: EmoContext - A Shared Task on Contextual Emotion Detection in Text. We propose a three layer model with a generic, multi-purpose approach that without any task specific optimizations achieve competitive results (f1 score of 0.7096) in the EmoContext task. We describe our development strategy in detail along with an exposition of our results.
Tasks
Published 2019-06-01
URL https://www.aclweb.org/anthology/S19-2037/
PDF https://www.aclweb.org/anthology/S19-2037
PWC https://paperswithcode.com/paper/gensmt-at-semeval-2019-task-3-contextual
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