Ivan Habernal


2021

pdf bib
Proceedings of the 16th Conference of the European Chapter of the Association for Computational Linguistics: Tutorial Abstracts
Isabelle Augenstein | Ivan Habernal
Proceedings of the 16th Conference of the European Chapter of the Association for Computational Linguistics: Tutorial Abstracts

pdf bib
When differential privacy meets NLP: The devil is in the detail
Ivan Habernal
Proceedings of the 2021 Conference on Empirical Methods in Natural Language Processing

Differential privacy provides a formal approach to privacy of individuals. Applications of differential privacy in various scenarios, such as protecting users’ original utterances, must satisfy certain mathematical properties. Our contribution is a formal analysis of ADePT, a differentially private auto-encoder for text rewriting (Krishna et al, 2021). ADePT achieves promising results on downstream tasks while providing tight privacy guarantees. Our proof reveals that ADePT is not differentially private, thus rendering the experimental results unsubstantiated. We also quantify the impact of the error in its private mechanism, showing that the true sensitivity is higher by at least factor 6 in an optimistic case of a very small encoder’s dimension and that the amount of utterances that are not privatized could easily reach 100% of the entire dataset. Our intention is neither to criticize the authors, nor the peer-reviewing process, but rather point out that if differential privacy applications in NLP rely on formal guarantees, these should be outlined in full and put under detailed scrutiny.

2020

pdf bib
Why do you think that? Exploring Faithful Sentence-Level Rationales Without Supervision
Max Glockner | Ivan Habernal | Iryna Gurevych
Findings of the Association for Computational Linguistics: EMNLP 2020

Evaluating the trustworthiness of a model’s prediction is essential for differentiating between ‘right for the right reasons’ and ‘right for the wrong reasons’. Identifying textual spans that determine the target label, known as faithful rationales, usually relies on pipeline approaches or reinforcement learning. However, such methods either require supervision and thus costly annotation of the rationales or employ non-differentiable models. We propose a differentiable training–framework to create models which output faithful rationales on a sentence level, by solely applying supervision on the target task. To achieve this, our model solves the task based on each rationale individually and learns to assign high scores to those which solved the task best. Our evaluation on three different datasets shows competitive results compared to a standard BERT blackbox while exceeding a pipeline counterpart’s performance in two cases. We further exploit the transparent decision–making process of these models to prefer selecting the correct rationales by applying direct supervision, thereby boosting the performance on the rationale–level.

2018

pdf bib
SemEval-2018 Task 12: The Argument Reasoning Comprehension Task
Ivan Habernal | Henning Wachsmuth | Iryna Gurevych | Benno Stein
Proceedings of The 12th International Workshop on Semantic Evaluation

A natural language argument is composed of a claim as well as reasons given as premises for the claim. The warrant explaining the reasoning is usually left implicit, as it is clear from the context and common sense. This makes a comprehension of arguments easy for humans but hard for machines. This paper summarizes the first shared task on argument reasoning comprehension. Given a premise and a claim along with some topic information, the goal was to automatically identify the correct warrant among two candidates that are plausible and lexically close, but in fact imply opposite claims. We describe the dataset with 1970 instances that we built for the task, and we outline the 21 computational approaches that participated, most of which used neural networks. The results reveal the complexity of the task, with many approaches hardly improving over the random accuracy of about 0.5. Still, the best observed accuracy (0.712) underlines the principle feasibility of identifying warrants. Our analysis indicates that an inclusion of external knowledge is key to reasoning comprehension.

pdf bib
Before Name-Calling: Dynamics and Triggers of Ad Hominem Fallacies in Web Argumentation
Ivan Habernal | Henning Wachsmuth | Iryna Gurevych | Benno Stein
Proceedings of the 2018 Conference of the North American Chapter of the Association for Computational Linguistics: Human Language Technologies, Volume 1 (Long Papers)

Arguing without committing a fallacy is one of the main requirements of an ideal debate. But even when debating rules are strictly enforced and fallacious arguments punished, arguers often lapse into attacking the opponent by an ad hominem argument. As existing research lacks solid empirical investigation of the typology of ad hominem arguments as well as their potential causes, this paper fills this gap by (1) performing several large-scale annotation studies, (2) experimenting with various neural architectures and validating our working hypotheses, such as controversy or reasonableness, and (3) providing linguistic insights into triggers of ad hominem using explainable neural network architectures.

pdf bib
The Argument Reasoning Comprehension Task: Identification and Reconstruction of Implicit Warrants
Ivan Habernal | Henning Wachsmuth | Iryna Gurevych | Benno Stein
Proceedings of the 2018 Conference of the North American Chapter of the Association for Computational Linguistics: Human Language Technologies, Volume 1 (Long Papers)

Reasoning is a crucial part of natural language argumentation. To comprehend an argument, one must analyze its warrant, which explains why its claim follows from its premises. As arguments are highly contextualized, warrants are usually presupposed and left implicit. Thus, the comprehension does not only require language understanding and logic skills, but also depends on common sense. In this paper we develop a methodology for reconstructing warrants systematically. We operationalize it in a scalable crowdsourcing process, resulting in a freely licensed dataset with warrants for 2k authentic arguments from news comments. On this basis, we present a new challenging task, the argument reasoning comprehension task. Given an argument with a claim and a premise, the goal is to choose the correct implicit warrant from two options. Both warrants are plausible and lexically close, but lead to contradicting claims. A solution to this task will define a substantial step towards automatic warrant reconstruction. However, experiments with several neural attention and language models reveal that current approaches do not suffice.

pdf bib
Computational Argumentation: A Journey Beyond Semantics, Logic, Opinions, and Easy Tasks
Ivan Habernal
Proceedings of the Workshop on Computational Semantics beyond Events and Roles

The classical view on argumentation, such that arguments are logical structures consisting of different distinguishable parts and that parties exchange arguments in a rational way, is prevalent in textbooks but nonexistent in the real world. Instead, argumentation is a multifaceted communication tool built upon humans’ capabilities to easily use common sense, emotions, and social context. As humans, we are pretty good at it. Computational Argumentation tries to tackle these phenomena but has a long and not so easy way to go. In this talk, I would like to shed a light on several recent attempts to deal with argumentation computationally, such as addressing argument quality, understanding argument reasoning, dealing with fallacies, and how should we never ever argue online.

pdf bib
Adapting Serious Game for Fallacious Argumentation to German: Pitfalls, Insights, and Best Practices
Ivan Habernal | Patrick Pauli | Iryna Gurevych
Proceedings of the Eleventh International Conference on Language Resources and Evaluation (LREC 2018)

2017

pdf bib
Argumentation Mining in User-Generated Web Discourse
Ivan Habernal | Iryna Gurevych
Computational Linguistics, Volume 43, Issue 1 - April 2017

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.

pdf bib
What is the Essence of a Claim? Cross-Domain Claim Identification
Johannes Daxenberger | Steffen Eger | Ivan Habernal | Christian Stab | Iryna Gurevych
Proceedings of the 2017 Conference on Empirical Methods in Natural Language Processing

Argument mining has become a popular research area in NLP. It typically includes the identification of argumentative components, e.g. claims, as the central component of an argument. We perform a qualitative analysis across six different datasets and show that these appear to conceptualize claims quite differently. To learn about the consequences of such different conceptualizations of claim for practical applications, we carried out extensive experiments using state-of-the-art feature-rich and deep learning systems, to identify claims in a cross-domain fashion. While the divergent conceptualization of claims in different datasets is indeed harmful to cross-domain classification, we show that there are shared properties on the lexical level as well as system configurations that can help to overcome these gaps.

pdf bib
Argotario: Computational Argumentation Meets Serious Games
Ivan Habernal | Raffael Hannemann | Christian Pollak | Christopher Klamm | Patrick Pauli | Iryna Gurevych
Proceedings of the 2017 Conference on Empirical Methods in Natural Language Processing: System Demonstrations

An important skill in critical thinking and argumentation is the ability to spot and recognize fallacies. Fallacious arguments, omnipresent in argumentative discourse, can be deceptive, manipulative, or simply leading to ‘wrong moves’ in a discussion. Despite their importance, argumentation scholars and NLP researchers with focus on argumentation quality have not yet investigated fallacies empirically. The nonexistence of resources dealing with fallacious argumentation calls for scalable approaches to data acquisition and annotation, for which the serious games methodology offers an appealing, yet unexplored, alternative. We present Argotario, a serious game that deals with fallacies in everyday argumentation. Argotario is a multilingual, open-source, platform-independent application with strong educational aspects, accessible at www.argotario.net.

pdf bib
Argumentation Quality Assessment: Theory vs. Practice
Henning Wachsmuth | Nona Naderi | Ivan Habernal | Yufang Hou | Graeme Hirst | Iryna Gurevych | Benno Stein
Proceedings of the 55th Annual Meeting of the Association for Computational Linguistics (Volume 2: Short Papers)

Argumentation quality is viewed differently in argumentation theory and in practical assessment approaches. This paper studies to what extent the views match empirically. We find that most observations on quality phrased spontaneously are in fact adequately represented by theory. Even more, relative comparisons of arguments in practice correlate with absolute quality ratings based on theory. Our results clarify how the two views can learn from each other.

pdf bib
Proceedings of the 4th Workshop on Argument Mining
Ivan Habernal | Iryna Gurevych | Kevin Ashley | Claire Cardie | Nancy Green | Diane Litman | Georgios Petasis | Chris Reed | Noam Slonim | Vern Walker
Proceedings of the 4th Workshop on Argument Mining

2016

pdf bib
What makes a convincing argument? Empirical analysis and detecting attributes of convincingness in Web argumentation
Ivan Habernal | Iryna Gurevych
Proceedings of the 2016 Conference on Empirical Methods in Natural Language Processing

pdf bib
Which argument is more convincing? Analyzing and predicting convincingness of Web arguments using bidirectional LSTM
Ivan Habernal | Iryna Gurevych
Proceedings of the 54th Annual Meeting of the Association for Computational Linguistics (Volume 1: Long Papers)

pdf bib
C4Corpus: Multilingual Web-size Corpus with Free License
Ivan Habernal | Omnia Zayed | Iryna Gurevych
Proceedings of the Tenth International Conference on Language Resources and Evaluation (LREC'16)

Large Web corpora containing full documents with permissive licenses are crucial for many NLP tasks. In this article we present the construction of 12 million-pages Web corpus (over 10 billion tokens) licensed under CreativeCommons license family in 50+ languages that has been extracted from CommonCrawl, the largest publicly available general Web crawl to date with about 2 billion crawled URLs. Our highly-scalable Hadoop-based framework is able to process the full CommonCrawl corpus on 2000+ CPU cluster on the Amazon Elastic Map/Reduce infrastructure. The processing pipeline includes license identification, state-of-the-art boilerplate removal, exact duplicate and near-duplicate document removal, and language detection. The construction of the corpus is highly configurable and fully reproducible, and we provide both the framework (DKPro C4CorpusTools) and the resulting data (C4Corpus) to the research community.

pdf bib
Crowdsourcing a Large Dataset of Domain-Specific Context-Sensitive Semantic Verb Relations
Maria Sukhareva | Judith Eckle-Kohler | Ivan Habernal | Iryna Gurevych
Proceedings of the Tenth International Conference on Language Resources and Evaluation (LREC'16)

We present a new large dataset of 12403 context-sensitive verb relations manually annotated via crowdsourcing. These relations capture fine-grained semantic information between verb-centric propositions, such as temporal or entailment relations. We propose a novel semantic verb relation scheme and design a multi-step annotation approach for scaling-up the annotations using crowdsourcing. We employ several quality measures and report on agreement scores. The resulting dataset is available under a permissive CreativeCommons license at www.ukp.tu-darmstadt.de/data/verb-relations/. It represents a valuable resource for various applications, such as automatic information consolidation or automatic summarization.

2015

pdf bib
Exploiting Debate Portals for Semi-Supervised Argumentation Mining in User-Generated Web Discourse
Ivan Habernal | Iryna Gurevych
Proceedings of the 2015 Conference on Empirical Methods in Natural Language Processing

2014

pdf bib
Sarcasm Detection on Czech and English Twitter
Tomáš Ptáček | Ivan Habernal | Jun Hong
Proceedings of COLING 2014, the 25th International Conference on Computational Linguistics: Technical Papers

2013

pdf bib
Unsupervised Improving of Sentiment Analysis Using Global Target Context
Tomáš Brychcín | Ivan Habernal
Proceedings of the International Conference Recent Advances in Natural Language Processing RANLP 2013

pdf bib
Sentiment Analysis in Czech Social Media Using Supervised Machine Learning
Ivan Habernal | Tomáš Ptáček | Josef Steinberger
Proceedings of the 4th Workshop on Computational Approaches to Subjectivity, Sentiment and Social Media Analysis