Report Number: CS-TR-68-103
Institution: Stanford University, Department of Computer Science
Title: Lexical insertion in transformational grammar
Author: Friedman, Joyce
Author: Bredt, Thomas H.
Date: June 1968
Abstract: In this paper, we describe the lexical insertion process for
generative transformational grammars. We also give detailed
descriptions of many of the concepts in transformational
theory. These include the notions of complex symbol,
syntactic feature (particularly contextual feature),
redundancy rule, tests for pairs of complex symbols, and
change operations that may be applied to complex symbols.
Because of our general interpretation of redundancy rules, we
define a new complex symbol test known as compatibility. This
test replaces the old notion of nondistinctness. The form of
a lexicon suitable for use with a generative grammar is
In lexical insertion, vocabulary words and associated complex
symbols are selected from a lexicon and inserted at lexical
category nodes in the tree. Complex symbols are lists of
syntactic features. The compatibility of a pair of complex
symbols and the analysis procedure used for contextual
features are basic in determining suitable items for
insertion. Contextual features (subcategorization and
selectional) have much in common with the structural
description for a transformation and we use the same analysis
procedure for both. A problem encountered in the insertion of
a complex symbol that contains selectional features is side
effects. We define the notion of side effects and describe
how these effects are to be treated.
The development of the structure of the lexicon and the
lexical insertion algorithm has been aided by a system of
computer programs that enable the linguist to study
transformational grammar. In the course of this development,
a computer program to perform lexical insertion was written.
Results obtained using this program with fragments of
transformational grammar are presented. The paper concludes
with suggestions for extensions of this work and a discussion
of interpretations of transformational theory that do not fit
immediately into our framework.