Roget’s Thesaurus has gone through many revisions since it was first published 150 years ago. But how do these revisions affect Roget’s usefulness for NLP? We examine the differences in content between the 1911 and 1987 versions of Roget’s, and we test both versions with each other and WordNet on problems such as synonym identification and word relatedness. We also present a novel method for measuring sentence relatedness that can be implemented in either version of Roget’s or in WordNet. .
