Tractable Parsing for CCGs of Bounded Degree

Unlike other mildly context-sensitive formalisms, Combinatory Categorial Grammar (CCG) cannot be parsed in polynomial time when the size of the grammar is taken into account. Refining this result, we show that the parsing complexity of CCG is exponential only in the maximum degree of composition. Wh...

Full description

Saved in:
Bibliographic Details
Published inComputational linguistics - Association for Computational Linguistics Vol. 48; no. 3; pp. 593 - 633
Main Authors Schiffer, Lena Katharina, Kuhlmann, Marco, Satta, Giorgio
Format Journal Article
LanguageEnglish
Published One Broadway, 12th Floor, Cambridge, Massachusetts 02142, USA MIT Press 01.09.2022
MIT Press Journals, The
The MIT Press
Subjects
Categorial grammar
Complexity
Composition
Grammars
Natural language
Parsing
Polynomials
Online AccessGet full text

Cover

More Information
Summary:Unlike other mildly context-sensitive formalisms, Combinatory Categorial Grammar (CCG) cannot be parsed in polynomial time when the size of the grammar is taken into account. Refining this result, we show that the parsing complexity of CCG is exponential only in the maximum degree of composition. When that degree is fixed, parsing can be carried out in polynomial time. Our finding is interesting from a linguistic perspective because a bounded degree of composition has been suggested as a universal constraint on natural language grammar. Moreover, ours is the first complexity result for a version of CCG that includes substitution rules, which are used in practical grammars but have been ignored in theoretical work.
Bibliography:2022
ISSN:0891-2017
1530-9312
1530-9312
DOI:10.1162/coli_a_00441