Over-Answering Yes-No Questions: Extended Responses in a NL Interface to a Vision System

Abstract

This paper addresses the problem of overanswering yes-no questions, i.e. of generating extended responses that provide additional information to yes-no questions that pragmatically must be interpreted as wh-questions. Although the general notion of extended responses has already been explored, our paper reports on the first attempt to build a NL system able to elaborate on a response as a result of anticipating obvious follow-up questions, in particular by providing additional case role fillers, by using more specific quantifiers and by generating partial answers to both parts of questions containing coordinating conjunctions. As a further innovation, the system explicitly deals with the informativeness-simplicity tradeoff when generating extended responses. We describe both an efficient implementation of the proposed methods, which use message passing as realized by the FLAVOR mechanism and the extensive linguistic knowledge incorporated in the verbalization component. The structure of the implemented NL generation component is illustrated using a detailed example of the systems"s performance as an interface to an image understanding system. 1.