Automatic labeling of contrastive word pairs from spontaneous spoken english

This paper addresses the problem of automatically labeling contrast in spontaneous spoken speech, where contrast here is meant as a relation that ties two words that explicitly contrast with each other. Detection of contrast is certainly relevant in the analysis of discourse and information structure and also, because of the prosodic correlates of contrast, could play an important role in speech applications, such as text-to-speech synthesis, that need an accurate and discourse context related modeling of prosody. With this prospect we investigate the feasibility of automatic contrast labeling by training and evaluating on the Switchboard corpus a novel contrast tagger, based on support vector machines (SVM), that combines lexical features, syntactic dependencies and WordNet semantic relations.