Benjamin Sznajder


2019

pdf bib
Financial Event Extraction Using Wikipedia-Based Weak Supervision
Liat Ein-Dor | Ariel Gera | Orith Toledo-Ronen | Alon Halfon | Benjamin Sznajder | Lena Dankin | Yonatan Bilu | Yoav Katz | Noam Slonim
Proceedings of the Second Workshop on Economics and Natural Language Processing

Extraction of financial and economic events from text has previously been done mostly using rule-based methods, with more recent works employing machine learning techniques. This work is in line with this latter approach, leveraging relevant Wikipedia sections to extract weak labels for sentences describing economic events. Whereas previous weakly supervised approaches required a knowledge-base of such events, or corresponding financial figures, our approach requires no such additional data, and can be employed to extract economic events related to companies which are not even mentioned in the training data.

pdf bib
Argument Invention from First Principles
Yonatan Bilu | Ariel Gera | Daniel Hershcovich | Benjamin Sznajder | Dan Lahav | Guy Moshkowich | Anael Malet | Assaf Gavron | Noam Slonim
Proceedings of the 57th Annual Meeting of the Association for Computational Linguistics

Competitive debaters often find themselves facing a challenging task – how to debate a topic they know very little about, with only minutes to prepare, and without access to books or the Internet? What they often do is rely on ”first principles”, commonplace arguments which are relevant to many topics, and which they have refined in past debates. In this work we aim to explicitly define a taxonomy of such principled recurring arguments, and, given a controversial topic, to automatically identify which of these arguments are relevant to the topic. As far as we know, this is the first time that this approach to argument invention is formalized and made explicit in the context of NLP. The main goal of this work is to show that it is possible to define such a taxonomy. While the taxonomy suggested here should be thought of as a ”first attempt” it is nonetheless coherent, covers well the relevant topics and coincides with what professional debaters actually argue in their speeches, and facilitates automatic argument invention for new topics.

2018

pdf bib
Learning Concept Abstractness Using Weak Supervision
Ella Rabinovich | Benjamin Sznajder | Artem Spector | Ilya Shnayderman | Ranit Aharonov | David Konopnicki | Noam Slonim
Proceedings of the 2018 Conference on Empirical Methods in Natural Language Processing

We introduce a weakly supervised approach for inferring the property of abstractness of words and expressions in the complete absence of labeled data. Exploiting only minimal linguistic clues and the contextual usage of a concept as manifested in textual data, we train sufficiently powerful classifiers, obtaining high correlation with human labels. The results imply the applicability of this approach to additional properties of concepts, additional languages, and resource-scarce scenarios.

2017

pdf bib
Unsupervised corpus–wide claim detection
Ran Levy | Shai Gretz | Benjamin Sznajder | Shay Hummel | Ranit Aharonov | Noam Slonim
Proceedings of the 4th Workshop on Argument Mining

Automatic claim detection is a fundamental argument mining task that aims to automatically mine claims regarding a topic of consideration. Previous works on mining argumentative content have assumed that a set of relevant documents is given in advance. Here, we present a first corpus– wide claim detection framework, that can be directly applied to massive corpora. Using simple and intuitive empirical observations, we derive a claim sentence query by which we are able to directly retrieve sentences in which the prior probability to include topic-relevant claims is greatly enhanced. Next, we employ simple heuristics to rank the sentences, leading to an unsupervised corpus–wide claim detection system, with precision that outperforms previously reported results on the task of claim detection given relevant documents and labeled data.