Clause anaphora resolution of Japanese demonstrative determiner by ontology extension using distributed expression of words

An anaphora is a type of expression whose reference depends upon another referential element. In order to become aware of situations or human intentions by natural language understanding, it is important to estimate correctly what anaphoric expressions indicate. In particular, an anaphora resolution for Japanese demonstrative determiners is critical to be aware of situation, context or a causal relationship in dialogue. Ontology-based similarity has been proposed as a way to identify referential elements; however, a method using ontology alone cannot resolve all anaphoric relations. This paper proposes an anaphora analysis method that uses semantic similarity between different parts-of-speech and conceptual dependency structure. This method specializes in resolving clause anaphoric. The evaluation of this method showed around 2% accuracy for resolving Japanese demonstrative determiner in balanced corpus.