Novel terms and cooperation in a natural language interface

Abstract

An approach for dealing with novel terms in input to a natural language interface to databases is presented. Traditionally terms not found in the lexicon are assumed to be database values. It is thus taken for granted that customization is complete, i.e., the lexicon contains all synonyms for all attributes. The problem then becomes one of determining the attribute of which the novel term is a value. The present approach entertains the possibility that the novel term is either a database value or a structural term. We argue that there are linguistic phenomena which in conjunction with the usual methods of defining database values can be used to distinguish between values and structural terms. Novel terms are treated as ambiguous, and the interface attempts to constrain the set of candidate interpretations using certain heuristics. If these methods fail to disambiguate the term, a focussed, informative response is generated for the set of interpretations. When appropriate, the user is solicited for information which the interface uses to create a lexical entry for the previously novel term.