The Limits of Unification

Current complex-feature based grammars use a single procedure--unification--for a multitude of purposes, among them, enforcing formal agreement between purely syntactic features. This paper presents evidence from several natural languages that unification--variable-matching combined with variable substitution--is the wrong mechanism for effecting agreement. The view of grammar developed here is one in which unification is used for semantic interpretation, while purely formal agreement involves only a check for non-distinctness---i.e, variable-matching without variable substitution.

• Type: Conference
• Year: 1990
• Where: ACL
• Authors: Robert Ingria
• Keywords: ACL 1990, ACL 2007, Complex-feature Based Grammars, Formal Agreement, Paper Presents Evidence