Integrating Knowledge Sources for the Speci cation of aTask - Oriented

We show how the speciication of a dialogue system can be divided into domain-dependent and domain-independent parts. We demonstrate how comparisons of actual representations in the dialogue history can help to infer hierarchical dialogue structure. The principles guiding the inference can be expressed in domain independent rules. Using typed feature structures as the only representation formalism we retain the simplicity of frame-based systems in terms of gathering necessary information to fulll a task. On the other hand, being able to easily integrate a type hierarchy into the representations and describing the systems behavior in clauses quantifying over feature structures in the dialogue history, we not only achieve a compact speciication of the system's behavior. The described implementation is a rst step towards the implementation of domain-independent task-oriented dialogue processing systems.