tailieunhanh - Báo cáo khoa học: "Generating Focused Topic-specific Sentiment Lexicons"

We present a method for automatically generating focused and accurate topicspecific subjectivity lexicons from a general purpose polarity lexicon that allow users to pin-point subjective on-topic information in a set of relevant documents. We motivate the need for such lexicons in the field of media analysis, describe a bootstrapping method for generating a topic-specific lexicon from a general purpose polarity lexicon, and evaluate the quality of the generated lexicons both manually and using a TREC Blog track test set for opinionated blog post retrieval. . | Generating Focused Topic-specific Sentiment Lexicons Valentin Jijkoun Maarten de Rijke Wouter Weerkamp ISLA University of Amsterdam The Netherlands jijkoun derijke Abstract We present a method for automatically generating focused and accurate topicspecific subjectivity lexicons from a general purpose polarity lexicon that allow users to pin-point subjective on-topic information in a set of relevant documents. We motivate the need for such lexicons in the field of media analysis describe a bootstrapping method for generating a topic-specific lexicon from a general purpose polarity lexicon and evaluate the quality of the generated lexicons both manually and using a TREC Blog track test set for opinionated blog post retrieval. Although the generated lexicons can be an order of magnitude more selective than the general purpose lexicon they maintain or even improve the performance of an opinion retrieval system. 1 Introduction In the area of media analysis one of the key tasks is collecting detailed information about opinions and attitudes toward specific topics from various sources both offline traditional newspapers archives and online news sites blogs forums . Specifically media analysis concerns the following system task given a topic and list of documents discussing the topic find all instances of attitudes toward the topic . positive negative sentiments or if the topic is an organization or person support criticism of this entity . For every such instance one should identify the source of the sentiment the polarity and possibly subtopics that this attitude relates to . specific targets of criticism or support . Subsequently a human media analyst must be able to aggregate the extracted information by source polarity or subtopics allowing him to build support criticism networks etc. Altheide 1996 . Recent advances in language technology especially in sentiment analysis promise to partially automate this task. Sentiment analysis is often .