Exploiting Convergence to Improve Natural Language Understanding

Abstract Convergence is the phenomenon in human dialogue whereby participants adopt characteristics of each other's speech. Communicants are unaware of this occurring. If it were possible to invoke such a phenomenon in a natural language interface it would provide a means of keeping user inputs within the range of lexical and syntactic coverage of the system, while keeping the dialogue ‘natural’ in the sense of requiring no more conscious effort in observing conventions of format than human-human dialogue. A ‘Wizard of Oz’ study was conducted to test the feasibility of this technique. Subjects were required to type queries into what they thought was a natural language database querying system. On completion of input the system presented a paraphrase for confirmation by subjects before presenting the answer. The paraphrases were constructed using particular terms and syntactic structures. Subjects began to use these terms and structures spontaneously in subsequent queries. Observation of convergence in human-computer dialogue suggests that the technique can be incorporated in user interfaces to improve communication. The implementation issues for natural language dialogue are discussed, and other applications of the technique in HCI are outlined.