Integration of finite-state morphological models to top-down syntactic parsers in prolog

• Main Author: Simard, Michel
• Format: Others
• Language: en
• Published: McGill University 1990
• Subjects: Computer Science.
• Online Access: http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=59440

Finite-state morphological models are formalisms for describing the set of valid word-forms of a natural language. Being well-suited for computer implementations, they have typically been used for creating systems that efficiently recognize and generate isolated word-forms. DCGs (Definite-clause Grammars) on the other hand, like many other syntactic formalisms closely connected with the programming language Prolog, are less suitable for describing morphological and orthographical phenomena (or phonological phenomena, in speech). This thesis describes a general method for combining the DCG syntactic formalism and a finite-state morphological model within a single Prolog implementation. The resulting system is a natural language processing environment that employs distinct formalisms for the descriptions of the syntax, morphology and orthography. The proposed method can readily be extended to other morphological models and syntactic formalisms (Metamorphosis Grammars, Extraposition Grammars). Modifications are discussed to improve the performance of the system, and a complete example illustrating the application of the proposed method is presented.