A Case Driven Parser For Natural Language
This paper describes a system for analysing natural language based on the concept of case. After a preliminary parse using an augmented transition network, the case routines attempt to find the appropriate verb meaning. These routines search for parts of the syntactic structure which best satisfy the requirements of the verb case frames and under back-up are able to weaken gradually the conditions for success. The resulting structure is similar to the conceptual dependency networks of Schank, and is an attempt to represent as fully as possible the meaning of the input sentence. The system has been designed to be quite flexible and allows for the incorporation of domain specific knowledge. This knowledge has its effect both in the nature of the dictionary and in modifications in the search routines. At present the system incorporates procedures for resolving anaphoric references which depend on examining previous sentences.