1,929 research outputs found
Analysis on the TGA Model for Stance Detection
Stance detection, a problem concerned with finding the stance that an author takes on a specific issue, is a large subset of NLP and A.I, and its uses can already be seen in a multitude of applications. The majority of stance detection machine learning models are tested against a popular dataset called SemEval2016, which is a collection of tweets, authors, topics and stances that were derived from Twitter data and the Twitter API. Many researchers across the globe have created machine learning models to accurately predict the stance of authors based on their tweets regarding a certain topic. However, recently, researchers at Columbia university have created a new dataset called VAST along with a model called Topic-Grouped Attention (TGA), or better known as the TGANet, that claims to perform well on zero-shot and few-shot stance detection, which is a subset of stance detection that focuses on determining the stance of authors on new, never seen topics. Their VAST dataset focuses on this zero-shot and few-shot sub-problem by including a large variety of topics. This VAST dataset has many more topics than traditional stance detection datasets, which often focus on a particular subject to focus their topics around. In this thesis paper, we analyze how the TGA model performs on the SemEval2016 dataset and determine whether the TGA model improves on the current existing zero shot and few-shot stance detection models
Deep Neural Attention for Misinformation and Deception Detection
PhD thesis in Information technologyAt present the influence of social media on society is so much that without it life seems to have no meaning for many. This kind of over-reliance on social media gives an opportunity to the anarchic elements to take undue advantage. Online misinformation and deception are vivid examples of such phenomenon. The misinformation or fake news spreads faster and wider than the true news [32]. The need of the hour is to identify and curb the spread of misinformation and misleading content automatically at the earliest.
Several machine learning models have been proposed by the researchers to detect and prevent misinformation and deceptive content. However, these prior works suffer from some limitations: First, they either use feature engineering heavy methods or use intricate deep neural architectures, which are not so transparent in terms of their internal working and decision making. Second, they do not incorporate and learn the available auxiliary and latent cues and patterns, which can be very useful in forming the adequate context for the misinformation. Third, Most of the former methods perform poorly in early detection accuracy measures because of their reliance on features that are usually absent at the initial stage of news or social media posts on social networks.
In this dissertation, we propose suitable deep neural attention based solutions to overcome these limitations. For instance, we propose a claim verification model, which learns embddings for the latent aspects such as author and subject of the claim and domain of the external evidence document. This enables the model to learn important additional context other than the textual content. In addition, we also propose an algorithm to extract evidential snippets out of external evidence documents, which serves as explanation of the model’s decisions. Next, we improve this model by using improved claim driven attention mechanism and also generate a topically diverse and non-redundant multi-document fact-checking summary for the claims, which helps to further interpret the model’s decision making. Subsequently, we introduce a novel method to learn influence and affinity relationships among the social media users present on the propagation paths of the news items. By modeling the complex influence relationship among the users, in addition to textual content, we learn the significant patterns pertaining to the diffusion of the news item on social network. The evaluation shows that the proposed model outperforms the other related methods in early detection performance with significant gains.
Next, we propose a synthetic headline generation based headline incongruence detection model. Which uses a word-to-word mutual attention based deep semantic matching between original and synthetic news headline to detect incongruence. Further, we investigate and define a new task of incongruence detection in presence of important cardinal values in headline. For this new task, we propose a part-of-speech pattern driven attention based method, which learns requisite context for cardinal values
Stance detection on social media: State of the art and trends
Stance detection on social media is an emerging opinion mining paradigm for
various social and political applications in which sentiment analysis may be
sub-optimal. There has been a growing research interest for developing
effective methods for stance detection methods varying among multiple
communities including natural language processing, web science, and social
computing. This paper surveys the work on stance detection within those
communities and situates its usage within current opinion mining techniques in
social media. It presents an exhaustive review of stance detection techniques
on social media, including the task definition, different types of targets in
stance detection, features set used, and various machine learning approaches
applied. The survey reports state-of-the-art results on the existing benchmark
datasets on stance detection, and discusses the most effective approaches. In
addition, this study explores the emerging trends and different applications of
stance detection on social media. The study concludes by discussing the gaps in
the current existing research and highlights the possible future directions for
stance detection on social media.Comment: We request withdrawal of this article sincerely. We will re-edit this
paper. Please withdraw this article before we finish the new versio
KCD: Knowledge Walks and Textual Cues Enhanced Political Perspective Detection in News Media
Political perspective detection has become an increasingly important task
that can help combat echo chambers and political polarization. Previous
approaches generally focus on leveraging textual content to identify stances,
while they fail to reason with background knowledge or leverage the rich
semantic and syntactic textual labels in news articles. In light of these
limitations, we propose KCD, a political perspective detection approach to
enable multi-hop knowledge reasoning and incorporate textual cues as
paragraph-level labels. Specifically, we firstly generate random walks on
external knowledge graphs and infuse them with news text representations. We
then construct a heterogeneous information network to jointly model news
content as well as semantic, syntactic and entity cues in news articles.
Finally, we adopt relational graph neural networks for graph-level
representation learning and conduct political perspective detection. Extensive
experiments demonstrate that our approach outperforms state-of-the-art methods
on two benchmark datasets. We further examine the effect of knowledge walks and
textual cues and how they contribute to our approach's data efficiency.Comment: accepted at NAACL 2022 main conferenc
Multi-Task Learning of Keyphrase Boundary Classification
Keyphrase boundary classification (KBC) is the task of detecting keyphrases
in scientific articles and labelling them with respect to predefined types.
Although important in practice, this task is so far underexplored, partly due
to the lack of labelled data. To overcome this, we explore several auxiliary
tasks, including semantic super-sense tagging and identification of multi-word
expressions, and cast the task as a multi-task learning problem with deep
recurrent neural networks. Our multi-task models perform significantly better
than previous state of the art approaches on two scientific KBC datasets,
particularly for long keyphrases.Comment: ACL 201
A Weakly Supervised Propagation Model for Rumor Verification and Stance Detection with Multiple Instance Learning
The diffusion of rumors on microblogs generally follows a propagation tree
structure, that provides valuable clues on how an original message is
transmitted and responded by users over time. Recent studies reveal that rumor
detection and stance detection are two different but relevant tasks which can
jointly enhance each other, e.g., rumors can be debunked by cross-checking the
stances conveyed by their relevant microblog posts, and stances are also
conditioned on the nature of the rumor. However, most stance detection methods
require enormous post-level stance labels for training, which are
labor-intensive given a large number of posts. Enlightened by Multiple Instance
Learning (MIL) scheme, we first represent the diffusion of claims with
bottom-up and top-down trees, then propose two tree-structured weakly
supervised frameworks to jointly classify rumors and stances, where only the
bag-level labels concerning claim's veracity are needed. Specifically, we
convert the multi-class problem into a multiple MIL-based binary classification
problem where each binary model focuses on differentiating a target stance or
rumor type and other types. Finally, we propose a hierarchical attention
mechanism to aggregate the binary predictions, including (1) a bottom-up or
top-down tree attention layer to aggregate binary stances into binary veracity;
and (2) a discriminative attention layer to aggregate the binary class into
finer-grained classes. Extensive experiments conducted on three Twitter-based
datasets demonstrate promising performance of our model on both claim-level
rumor detection and post-level stance classification compared with
state-of-the-art methods.Comment: Accepted by SIGIR 202
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