A Compositional Approach toward Dynamic Phrasal Thesaurus

To enhance the technology for computing semantic equivalence, we introduce the notion of phrasal thesaurus which is a natural extension of conventional word-based thesaurus. Among a variety of phrases that conveys the same meaning, i.e., paraphrases, we focus on syntactic variants that are compositionally explainable using a small number of atomic knowledge, and develop a system which dynamically generates such variants. This paper describes the proposed system and three sorts of knowledge developed for dynamic phrasal thesaurus in Japanese: (i) transformation pattern, (ii) generation function, and (iii) lexical function.