Dialogue management in the Talk´n´Travel system

A central problem for mixed-initiative dialogue management is coping with user utterances that fall outside of the expected sequence of dialogue. Independent initiative by the user may require a complete revision of the future course of the dialogue, even when the system is engaged in activities of its own, such as querying a database, etc. This paper presents an event-driven, goal-based dialogue manager component we have developed to cope with these challenges. The dialog manager is explicitly designed for asynchronous input and flexible control, and uses a tree-ordered rule language we have developed that also provides for close coupling with discourse processing. The dialogue manager is implemented as part of Talk´n´Travel, a simulated air travel reservation dialogue system we have developed under the US DARPA Communicator dialogue research program, whose purpose and scope we also briefly summarize.