Reconciling initiative and discourse structure

Abstract

In this paper we consider how initiative is managed in dialogue. We propose that initiative is subordinate to the intentional hierarchy of discourse structure. In dialogues from the TRAINS corpus we find that inside a segment initiated by one speaker, the other speaker only makes two types of contributions: a special kind of acknowledgment we call forward acknowledgments, and short contributions that add content to the segment. The proposal has important implications for dialogue management: a system only needs to model intentional structure, from which initiative follows.