- Yiming Yang, W. Wilbur. 1996. Using Corpus Statistics to Remove Redundant Words in Text Categorization. Abstract: This article studies aggressive word removal in text categorization to reduce the noise in free texts and to enhance the computational efficiency of categorization. We use a novel stop word identification method to automatically generate domain specific stoplists which are much larger than a conventional domain-independent stoplist. In our tests with three categorization methods on text collections from different domains/applications, significant numbers of words were removed without sacrificing categorization effectiveness. In the test of the Expert Network method on CACM documents, for example, an 87% removal of unique words reduced the vocabulary of documents from 8,002 distinct words to 1,045 words, which resulted in a 63% time savings and a 74% memory savings in the computation of category ranking, with a 10% precision improvement on average over not using word removal. It is evident in this study that automated word removal based on corpus statistics has a practical and significant impact on the computational tractability of categorization methods in large databases.
