A Tool for Collecting Domain Dependent Sortal Constraints From Corpora

In this paper, we describe a tool designed to generate semi-automatically the sortal constraints specific to a domain to be used in a natural language (NL) understanding system. This tool is evaluated using the SRI Gemini NL understanding system in the ATIS domain.

Interleaving Syntax and Semantics in an Efficient Bottom-Up Parser

We describe an efficient bottom-up parser that interleaves syntactic and semantic structure building. Two techniques are presented for reducing search by reducing local ambiguity: Limited left-context constraints are used to reduce local syntactic ambiguity, and deferred sortal-constraint application is used to reduce local semantic ambiguity. We experimentally evaluate these techniques, and show dramatic reductions in both number of chart-edges and total parsing time. The robust processing capabilities of the parser are demonstrated in its use in improving the accuracy of a speech recognizer.