Focusing in Dialog

Abstract

When two people talk, they focus their attention on only a small portion of what each of them knows or believes. Both what gets said and how it gets interpreted depend on a shared understanding of this narrowing of attention to a small highlighted portion of what is known. One of the effects of understanding an utterance is to be focused on certain entities (both relationships and objects) from a particular perspective. A speaker provides a hearer with clues to what to look at and how to look at it — what to focus on, how to focus on it, and how wide or narrow the focusing should be. These clues may be linguistic or they may come from knowledge about the relationships between entities in the domain. Linguistic clues may be either explicit, deriving directly from certain words, or implicit, deriving from sentential structure and from rhetorical relationships between sentences.

This paper examines focusing in dialog, discusses focusing mechanisms based on domain structure clues, and, from this perspective, indicates future research problems entailed in modeling the focusing process more generally. The importance of focusing is illustrated by considering the problem of generating an understanding definite descriptions.