Selection of Effective Contextual Information for Automatic Synonym Acquisition

Various methods have been proposed for automatic synonym acquisition, as synonyms are one of the most fundamental lexical knowledge. Whereas many methods are based on contextual clues of words, little attention has been paid to what kind of categories of contextual information are useful for the purpose. This study has experimentally investigated the impact of contextual information selection, by extracting three kinds of word relationships from corpora: dependency, sentence co-occurrence, and proximity. The evaluation result shows that while dependency and proximity perform relatively well by themselves, combination of two or more kinds of contextual information gives more stable performance. We've further investigated useful selection of dependency relations and modification categories, and it is found that modification has the greatest contribution, even greater than the widely adopted subjectobject combination.

• Type: Conference
• Year: 2006
• Where: ACL
• Authors: Masato Hagiwara, Yasuhiro Ogawa, Katsuhiko Toyama
• Keywords: ACL 2006, ACL 2007, Contextual Clues, Contextual Information, Contextual Information Selection