REQUEST: A Natural Language Question-Answering System
by W. J. Plath
REQUEST is an experimental Restricted English QUESTion-answering system that can analyze and answer a variety of English questions, spanning a significant range of syntactic complexity, with respect to a small Fortune-500-type data base. The long-range objective of this work is to explore the possibility of providing nonprogrammers with a convenient and powerful means of accessing information in formatted data bases without having to learn a formal query language. To address the somewhat conflicting requirements of understandability for the machine and maximum naturalness for the user, REQUEST uses a language processing approach featuring: 1) the use of restricted English; 2) a two-phase, complier-like organization; and 3) linguistic analysis based on a transformational grammar. The present paper explores the motivation for this approach in some detail and also describes the organization, operation, and current status of the system.