Constituent object parsing for information retrieval and similar text processing problems

The architecture and functioning of the Constituent Object Parser are described. This system has been developed specifically for text processing applications such as information retrieval, which can benefit from structural comparisons between elements of text such as a query and a potentially relevant abstract. The general way in which the system performs these matches, and the ways in which this objective influenced the design of the system are described. The parsing architecture incorporates several interesting features including: (1) an unusual combination of declarative and procedural representation techniques, (2) a monotonic discipline which permits useful heuristic approaches to difficult linguistic problems such as ellipsis, conjunction, ambiguity, and ill-formed and incomplete input, and (3) an attempt to minimize the level of syntactic detail required in both the grammar and the lexicon. © 1989 John Wiley & Sons, Inc.