To understand dialogue, we must solve mixed initiative, indirect speech act, sentence fragment, and resolving anaphora. In particular, the sentence fragment is frequently occurred in dialogue and is highly related to context and discourse situation. Since we can not solve it with only syntactic and semantic knowledge, we must use the context and the situational knowledge.
The sentence fragment is divided into two groups-elipsis and idiomatic expression. The elipsis is the intra-sentential fragment, the inter-sentential fragment, and the situational fragment. The idiomatic expression is the proverb the maxim, and the exclamatory phrase. We solve the inter-sentential fragment by using contextual knowledge and the situational fragment can be solved by using domain knowledge.
This paper describes a method for solving sentence fragment using the context and the situational knowledge. Using plan as a situation and a domain knowledge, the speaker's attention and intention can be recognized. By executing speaker's plan under control of speech act, we can make intended response and generate a expectation of next intention. The paper also describes a method for solving the mixed initiative and the indirect speech act.
