English

Using default inheritance to describe LTAG

cmp-lg 2016-08-31 v1 Computation and Language

Abstract

We present the results of an investigation into how the set of elementary trees of a Lexicalized Tree Adjoining Grammar can be represented in the lexical knowledge representation language DATR (Evans & Gazdar 1989a,b). The LTAG under consideration is based on the one described in Abeille et al. (1990). Our approach is similar to that of Vijay-Shanker & Schabes (1992) in that we formulate an inheritance hierarchy that efficiently encodes the elementary trees. However, rather than creating a new representation formalism for this task, we employ techniques of established utility in other lexically-oriented frameworks. In particular, we show how DATR's default mechanism can be used to eliminate the need for a non-immediate dominance relation in the descriptions of the surface LTAG entries. This allows us to embed the tree structures in the feature theory in a manner reminiscent of HPSG subcategorisation frames, and hence express lexical rules as relations over feature structures.

Keywords

Cite

@article{arxiv.cmp-lg/9501001,
  title  = {Using default inheritance to describe LTAG},
  author = {Roger Evans and Gerald Gazdar and David Weir},
  journal= {arXiv preprint arXiv:cmp-lg/9501001},
  year   = {2016}
}