关键词: 文本分类, 特征选择, 评价函数, 互信息比值

Abstract: Feature selection is a valid method to reduce the dimension of text vector in automatic text categorization system. After analyzing some normal evaluation functions for feature selection, a new evaluation function named the ratio of mutual information in feature selection was presented. Experiments show that the method is simple and feasible. It is advantageous in improving the efficiency of the selected feature subset.

Key words: text categorization, feature selection, evaluation function, ratio of mutual information