关键词: 文本褒贬倾向判别, 概率潜在语义分析, Fisher判别准则, 支持向量机

Abstract: On the basis of vector space model of text expression，a feature weight computing method for text commendatory-
derogatory orientation discrimination is proposed based on Probabilistic Latent Semantic Analysis（PLSA）.In addition to the word frequency of a feature，the information of its thesaurus and homoionym latently obtained by PLSA is taken in consideration to weight computing.Using the feature selection method based on Fisher criterion，and constructing a classifier with Support Vector Machine（SVM），an experiment is conducted under a Chinese review text corpus with size of 2 739 documents（COAE2008）.The experimental results indicate that the presented weight computing method based on PLSA is effective.

Key words: text commendatory-derogatory orientation discrimination, Probabilistic Latent Semantic Analysis（PLSA）, Fisher discrimination criterion, Support Vector Machine（SVM）