Focus Constraints on Language Generation

Abstract

Computer generation of natur al langua ge requir es th e ability to mak e r e ason e d c ho ice s from a larg e number o f possible things t o say as wel l as from a large number of exp r essive possibilities. This paper exa mi n es in d e t a il how one influ e n ce on a generated text, focus of a ttenti on , can b e us e d t o co n s train th e many possibilities that a ge neration system must consider . A computational treatm e nt of focu s of a tt e ntion i s pr e s e nt ed that ca n b e us e d to co nstr a in wh a t th e sys t e m n eeds to co n side r wh e n deciding what to say ne x t. In thi s process, information is produced th at provides constraints on whi c h words a nd syntactic structures best e xpr ess th e system's intent, thus ensuring that its resultin g t ex t is co h e r e nt . This analysis h as been us e d in the fully implemented TEX T sys t e m whi c h generates p a ragr aph length r esp onse s to questions about database structure.