Abstract
Clustering word co-occurrences has been studied to discover clusters as latent concepts. Previous work has applied the semantic aggregate model (SAM), and reports that discovered clusters seem semantically significant. The SAM assumes a co-occurrence arises from one latent concept. This assumption seems moderately natural. However, to analyze latent concepts more deeply, the assumption may be too restrictive. We propose to make clusters for each part of speech from co-occurrence data. For example, we make adjective clusters and noun clusters from adjective--noun co-occurrences while the SAM builds clusters of ``co-occurrences.'' The proposed approach allows us to analyze adjectives and nouns independently.
