Paper: Disjunctive Feature Structures As Hypergraphs

ACL ID C92-2076
Title Disjunctive Feature Structures As Hypergraphs
Venue International Conference on Computational Linguistics
Session Main Conference
Year 1992
  • Jean Veronis (CNRS, France; Vassar College, Poughkeepsie NY)

-- In this paper, we present a new math- ematical framework in which disjunctive feature structures are defined as directed acyclic hypergraphs. Disjunction is defined in the feature structure domain, and not at the syntactic level in feature descriptions. This enables us to study properties and specify operations in terms of properties of, or operations on, hypergraphs rather titan in syntactic terms. We illustrate the expressive power of this framework by defining a class of disjunctive feature structures with interesting properties (factored normal form or FNF), such as closure under factoring, unfactoring, unification, and generalization. Unification, in particular, has the intuitive appeal of preserving as much as possible the particular factoring of the disjunctive feature structures...