DelphinTutorial_Grammars

DELPH-IN Grammars

The GrammarCatalog page gives an overview of the existing DELPH-IN grammars.

Overview

A DELPH-IN grammar consists of a set of grammar entities which together license a set of strings together with linguistic structures for each string representing morphological, syntactic and semantic information.

The grammar entities bear declarative constraints which encode well-formedness restrictions as well as compositional semantics. There are three major categories of grammar entities:

• lexical entries giving form/meaning information about particular lemmas

• lexical rules which build words from lemmas and can add syntactic, semantic, and orthogaphic information

• phrase structure rules which build larger constituents from words

In addition, there are also two further categories of grammar entities:

• root symbols which any spanning edge must unify with to be output as a parse

• node labels used in the display of abbreviated trees

The constraints on the grammar entities are largely inherited from the type hierarchy. The type hierarchies in DELPH-IN grammars are singly-rooted and conform to the closed world assumption. Most of the work in developing a DELPH-IN grammar involves creating and maintaining the type hierarchy.

Structures

Treebanks

Creating new grammars