Paper: XTAG - A Graphical Workbench For Developing Tree-Adjoining Grammars

ACL ID A92-1030
Title XTAG - A Graphical Workbench For Developing Tree-Adjoining Grammars
Venue Applied Natural Language Processing Conference
Session Main Conference
Year 1992
Authors

We describe a workbench (XTAG) for the development of tree-adjoining grammars and their parsers, and dis- cuss some issues that arise in the design of the graphical interface. Contrary to string rewriting grammars generating trees, the elementary objects manipulated by a tree- adjoining grammar are extended trees (i.e. trees of depth one or more) which capture syntactic information of lex- ical items. The unique characteristics of tree-adjoining grammars, its elementary objects found in the ~ lexicon (extended trees) and the derivational history of derived trees (also a tree), require a specially crafted interface in which the perspective has Shifted from a string-based to a tree-based system. XTAG provides such a graphical interface in which the elementary objects are trees (or tree sets)...