A three-tiered parsing approach for operational systems

A three-tiered approach to parsing that takes advantage of as much syntactic and semantic information as needed to create accurate interpretations of input efficiently is described. While syntactic structure is assumed to be the fundamental basis for subsequent semantic interpretation, semantic analysis and insights from sublanguage analysis are utilized during parsing to produce a semantically constrained set of syntactic structures. This three-tiered approach combines theoretical insights with practical techniques to achieve a high rate of success in parsing large corpora of text containing difficult constructions. This is done by using insights from various approaches without bringing in the inadequacies of any one approach. The resulting hybrid system is not only general, flexible, and portable between various domains and applications, but is accurate and efficient in real-world settings