Reducing Over-Weighting in Supervised Term Weighting for Sentiment Analysis

Recently the research on supervised term weighting has attracted growing attention in the field of Traditional Text Categorization (TTC) and Sentiment Analysis (SA). Despite their impressive achievements, we show that existing methods more or less suffer from the problem of over-weighting. Overlooked by prior studies, over-weighting is a new concept proposed in this paper. To address this problem, two regularization techniques, singular term cutting and bias term, are integrated into our framework of supervised term weighting schemes. Using the concepts of over-weighting and regularization, we provide new insights into existing methods and present their regularized versions. Moreover, under the guidance of our framework, we develop a novel supervised term weighting scheme, regularized entropy (re). The proposed framework is evaluated on three datasets widely used in SA. The experimental results indicate that our re enjoys the best results in comparisons with existing methods, and regularization techniques can significantly improve the performances of existing supervised weighting methods.