Paper: A Treatment Of Negative Descriptions Of Typed Feature Structures

ACL ID C92-1059
Title A Treatment Of Negative Descriptions Of Typed Feature Structures
Venue International Conference on Computational Linguistics
Session Main Conference
Year 1992
Authors

A formal treatment of typed feature structures (TFSs) is developed to augment TFSs, so that neg- ative descriptions of them can be treated. Negative descriptions of TFSs can make linguistic descriptions compact and thus easy to understand. Negative de- scriptions can be classified into three primitive nega- tive descriptions: (1) negations of type symbols, (2) negations of feature existences, and (3) negations of feature-address value agreements. The formalization proposed in this paper is based on A'it-Kaci's com- plex terms. The first description is treated by extend- ing type symbol lattices to include complement type symbols. The second and third are treated by aug- meriting term structures with structures representing these negations. Algorithrrts for augmented-TFS uni- fication have ...