Automatic Extraction of Polar Adjectives for the Creation of Polarity Lexicons

Vázquez, Silvia; Padró, Muntsa; Bel Rafecas, Núria; Gonzalo, Julio

Automatic Extraction of Polar Adjectives for the Creation of Polarity Lexicons

Citation

Vázquez S, Padró M, Bel N, Gonzalo J. Automatic Extraction of Polar Adjectives for the Creation of Polarity Lexicons. In: Kay M, Boitet C, editors. Proceedings of COLING 2012: Posters: 24th International Conference on Computational Linguistics COLING 2012; 2012 December 8-15; Mumbai, India. Mumbai: The COLING 2012 Organizing Committee; 2012. p. 1271-1280.

Abstract

Automatic creation of polarity lexicons is a crucial issue to be solved in order to reduce time and/nefforts in the first steps of Sentiment Analysis. In this paper we present a methodology based on/nlinguistic cues that allows us to automatically discover, extract and label subjective adjectives/nthat should be collected in a domain-based polarity lexicon. For this purpose, we designed a/nbootstrapping algorithm that, from a small set of seed polar adjectives, is capable to iteratively/nidentify, extract and annotate positive and negative adjectives. Additionally, the method/nautomatically creates lists of highly subjective elements that change their prior polarity even/nwithin the same domain. The algorithm proposed reached a precision of 97.5% for positive/nadjectives and 71.4% for negative ones in the semantic orientation identification task.