Generalized phrase structure grammar

Generalized phrase structure grammar (GPSG) is a framework for describing the syntax and semantics of natural languages.

It is a type of constraint-based phrase structure grammar.

It is a type of constraint-based phrase structure grammar.

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.

In phrase structure grammars, such as generalised phrase structure grammar, head-driven phrase structure grammar and lexical functional grammar, a feature structure is essentially a set of attribute–value pairs.

One of the chief goals of GPSG is to show that the syntax of natural languages can be described by CFGs (written as ID/LP grammars), with some suitable conventions intended to make writing such grammars easier for syntacticians.

The idea first came to prominence as part of Generalized Phrase Structure Grammar; the ID/LP Grammar approach is also used in head-driven phrase structure grammar, lexical functional grammar, and other unification grammars.

GPSG was initially developed in the late 1970s by Gerald Gazdar.

Gazdar defined Linear Indexed Grammars and pioneered, along with his colleagues Ewan Klein, Geoffrey Pullum and Ivan Sag, the framework of Generalized Phrase Structure Grammars.

Other contributors include Ewan Klein, Ivan Sag, and Geoffrey Pullum.

His early work was as a member of the research teams that invented and developed head-driven phrase structure grammar (HPSG) as well as generalized phrase structure grammar, HPSG's immediate intellectual predecessor.

Most of the syntactic innovations of GPSG were subsequently incorporated into head-driven phrase structure grammar.

It is a type of phrase structure grammar, as opposed to a dependency grammar, and it is the immediate successor to generalized phrase structure grammar.

Other contributors include Ewan Klein, Ivan Sag, and Geoffrey Pullum.

GPSG was in part a reaction against transformational theories of syntax.

Generalized phrase structure grammar (GPSG) is a framework for describing the syntax and semantics of natural languages.

Generalized phrase structure grammar (GPSG) is a framework for describing the syntax and semantics of natural languages.

Constraint based grammars are based around defining certain syntactic processes as ungrammatical for a given language and assuming everything not thus dismissed is grammatical within that language.

This view stands in contrast to dependency grammars, which base their assumed structure on the relationship between a single word in a sentence (the sentence head) and its dependents.

In fact, the notational extensions to context-free grammars (CFGs) developed in GPSG are claimed to make transformations redundant.

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.

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.

One such method is a Syntax tree, which represents all of the words in a sentence as leaf nodes in a parsing tree, as can be seen in the provided image.

X-bar theory was incorporated into both transformational and nontransformational theories of syntax, including GB, GPSG, LFG, and HPSG.

Syntacticians generally hold that there are parametric points of variation between languages, although heated debate occurs over whether UG constraints are essentially universal due to being "hard-wired" (Chomsky's principles and parameters approach), a logical consequence of a specific syntactic architecture (the generalized phrase structure approach) or the result of functional constraints on communication (the functionalist approach).

This bottom-up view of structure generation is rejected by representational (non-derivational) theories (e.g. Generalized Phrase Structure Grammar, Head-Driven Phrase Structure Grammar, Lexical Functional Grammar, most dependency grammars, etc.), and it is contrary to early work in Transformational Grammar.