'Generalised phrase structure grammar' (GPSG) is a framework for describing the
syntax and
semantics of natural languages. GPSG was initially developed in the late 1970s by
Gerald Gazdar. Other contributors include
Ewan Klein,
Ivan Sag, and
Geoffrey Pullum. Their book ''Generalized Phrase Structure Grammar'', published in
1985, is the main monograph on GPSG, especially as it applies to English syntax.
One of the chief goals of GPSG is to show that the syntax of natural languages can be described by
context-free grammars (CFGs), with some suitable conventions intended to make writing such grammars easier for syntacticians. Among these conventions are a sophisticated
feature structure system and so-called "meta-rules", which are rules generating the productions of a context-free grammar. GPSG further augments syntactic descriptions with semantic annotations that can be used to compute the compositional meaning of a sentence from its syntactic derivation tree. However, it has been argued (for example by
Robert Berwick) that these extensions require
parsing algorithms of a higher order of
computational complexity than those used for basic CFGs.
Gerald Gazdar, and many other syntacticians, have since argued that natural languages cannot in fact be adequately described by CFGs
[1].
GPSG is in part a reaction against
transformational theories of syntax. In fact, the notational extensions to context-free grammars developed in GPSG are claimed to make transformations redundant. Most of the syntactic innovations of GPSG were subsequently incorporated into
head-driven phrase structure grammar.
References
★
Generalized Phrase Structure Grammar, , Gerald, Gazdar, Blackwell, and Cambridge, MA: Harvard University Press, 1985, ISBN 0-674-34455-3
See also
★
Lexical functional grammar
★
Transformational grammar
External links
★
Gerald Gazdar's homepage, containing links to publications on GPSG.