Computational Linguistics & Phonetics Computational Linguistics & Phonetics Fachrichtung 4.7 Universität des Saarlandes

Computational Linguistics Colloquium

Wednesday, 9 June 2010, 16:15
Seminar Room, Building C7 2

A lexicon-based approach to sentiment analysis

Maite Taboda
Department of Linguistics
Simon Fraser University, Burnaby, Canada

Sentiment analysis is the automatic extraction of information about opinion and subjectivity from text and speech. In this talk, I describe our current research in sentiment analysis. The Semantic Orientation CALculator (SO-CAL) uses dictionaries of words annotated with their semantic orientation (polarity and strength), and incorporates intensification and negation. I describe the process of dictionary creation, and our use of Mechanical Turk to check dictionaries for consistency and reliability. SO-CAL is applied to the polarity classification task, the process of assigning a positive or negative label to a text that captures the text’s opinion towards its main subject matter. I show that SO-CAL’s performance is consistent across domains and in completely unseen data. I also describe current research on using discourse information to improve performance.

If you would like to meet with the speaker, please contact Caroline Sporleder.