22,752 research outputs found
Unsupervised User Stance Detection on Twitter
We present a highly effective unsupervised framework for detecting the stance
of prolific Twitter users with respect to controversial topics. In particular,
we use dimensionality reduction to project users onto a low-dimensional space,
followed by clustering, which allows us to find core users that are
representative of the different stances. Our framework has three major
advantages over pre-existing methods, which are based on supervised or
semi-supervised classification. First, we do not require any prior labeling of
users: instead, we create clusters, which are much easier to label manually
afterwards, e.g., in a matter of seconds or minutes instead of hours. Second,
there is no need for domain- or topic-level knowledge either to specify the
relevant stances (labels) or to conduct the actual labeling. Third, our
framework is robust in the face of data skewness, e.g., when some users or some
stances have greater representation in the data. We experiment with different
combinations of user similarity features, dataset sizes, dimensionality
reduction methods, and clustering algorithms to ascertain the most effective
and most computationally efficient combinations across three different datasets
(in English and Turkish). We further verified our results on additional tweet
sets covering six different controversial topics. Our best combination in terms
of effectiveness and efficiency uses retweeted accounts as features, UMAP for
dimensionality reduction, and Mean Shift for clustering, and yields a small
number of high-quality user clusters, typically just 2--3, with more than 98\%
purity. The resulting user clusters can be used to train downstream
classifiers. Moreover, our framework is robust to variations in the
hyper-parameter values and also with respect to random initialization
Semantic Sentiment Analysis of Twitter Data
Internet and the proliferation of smart mobile devices have changed the way
information is created, shared, and spreads, e.g., microblogs such as Twitter,
weblogs such as LiveJournal, social networks such as Facebook, and instant
messengers such as Skype and WhatsApp are now commonly used to share thoughts
and opinions about anything in the surrounding world. This has resulted in the
proliferation of social media content, thus creating new opportunities to study
public opinion at a scale that was never possible before. Naturally, this
abundance of data has quickly attracted business and research interest from
various fields including marketing, political science, and social studies,
among many others, which are interested in questions like these: Do people like
the new Apple Watch? Do Americans support ObamaCare? How do Scottish feel about
the Brexit? Answering these questions requires studying the sentiment of
opinions people express in social media, which has given rise to the fast
growth of the field of sentiment analysis in social media, with Twitter being
especially popular for research due to its scale, representativeness, variety
of topics discussed, as well as ease of public access to its messages. Here we
present an overview of work on sentiment analysis on Twitter.Comment: Microblog sentiment analysis; Twitter opinion mining; In the
Encyclopedia on Social Network Analysis and Mining (ESNAM), Second edition.
201
Issue Framing in Online Discussion Fora
In online discussion fora, speakers often make arguments for or against
something, say birth control, by highlighting certain aspects of the topic. In
social science, this is referred to as issue framing. In this paper, we
introduce a new issue frame annotated corpus of online discussions. We explore
to what extent models trained to detect issue frames in newswire and social
media can be transferred to the domain of discussion fora, using a combination
of multi-task and adversarial training, assuming only unlabeled training data
in the target domain.Comment: To appear in NAACL-HLT 201
Spanish Corpora of tweets about COVID-19 vaccination for automatic stance detection
The paper presents new annotated corpora for performing stance detection on Spanish Twitter data, most notably Health-related tweets. The objectives of this research are threefold: (1) to develop a manually annotated benchmark corpus for emotion recognition taking into account different variants of Spanish in social posts; (2) to evaluate the efficiency of semi-supervised models for extending such corpus with unlabelled posts; and (3) to describe such short text corpora via specialised topic modelling. A corpus of 2,801 tweets about COVID-19 vaccination was annotated by three native speakers to be in favour (904), against (674) or neither (1,223) with a 0.725 Fleiss’ kappa score. Results show that the self-training method with SVM base estimator can alleviate annotation work while ensuring high model performance. The self-training model outperformed the other approaches and produced a corpus of 11,204 tweets with a macro averaged f1 score of 0.94. The combination of sentence-level deep learning embeddings and density-based clustering was applied to explore the contents of both corpora. Topic quality was measured in terms of the trustworthiness and the validation index.Agencia Estatal de Investigación | Ref. PID2020–113673RB-I00Xunta de Galicia | Ref. ED431C2018/55Fundação para a Ciência e a Tecnologia | Ref. UIDB/04469/2020Financiado para publicación en acceso aberto: Universidade de Vigo/CISU
Argumentation Mining in User-Generated Web Discourse
The goal of argumentation mining, an evolving research field in computational
linguistics, is to design methods capable of analyzing people's argumentation.
In this article, we go beyond the state of the art in several ways. (i) We deal
with actual Web data and take up the challenges given by the variety of
registers, multiple domains, and unrestricted noisy user-generated Web
discourse. (ii) We bridge the gap between normative argumentation theories and
argumentation phenomena encountered in actual data by adapting an argumentation
model tested in an extensive annotation study. (iii) We create a new gold
standard corpus (90k tokens in 340 documents) and experiment with several
machine learning methods to identify argument components. We offer the data,
source codes, and annotation guidelines to the community under free licenses.
Our findings show that argumentation mining in user-generated Web discourse is
a feasible but challenging task.Comment: Cite as: Habernal, I. & Gurevych, I. (2017). Argumentation Mining in
User-Generated Web Discourse. Computational Linguistics 43(1), pp. 125-17
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