DFKI Research Report-95-18



Language: English

by Hans-Ulrich Krieger, Ulrich Schäfer

Efficient Parameterizable Type Expansion for Typed Feature Formalisms

19 Pages


Over the last few years, constraint-based grammar formalisms have become the predominant paradigm in natural language processing and computational linguistics. From the viewpoint of computer science, typed feature structures can be seen as a record-like data structure that allow the representation of linguistic knowledge in a uniform fashion.

Type expansion is an operation that makes the idiosyncratic and inherited constraints defined on a typed feature structure explicit and thus determines its satisfiability. We describe an efficient expansion algorithm that takes care of recursive type definitions and permits the exploration of different expansion strategies through the use of control knowledge. This knowledge is specified on a separate layer, independent of grammatical information. The algorithm, as presented in the paper, has been fully implemented in COMMON LISP and is an integrated part of the typed feature formalism TDL that is employed in several large NL projects.

This document is available as Postscript.

The next abstract is here, and the previous abstract is here.

DFKI-Bibliothek (bib@dfki.uni-kl.de)

Note: This page was written to look best with CSS stylesheet support Level 1 or higher. Since you can see this, your browser obviously doesn't support CSS, or you have turned it off. We highly recommend you use a browser that supports and uses CSS, and review this page once you do. However, don't fear, we've tried to write this page to still work and be readable without CSS.