Corpus ID: 15036127

Pregroup Grammars and Context-free Grammars

@inproceedings{Buszkowski2007PregroupGA,
  title={Pregroup Grammars and Context-free Grammars},
  author={W. Buszkowski and K. Moroz},
  year={2007}
}
Pregroup grammars were introduced by Lambek [20] as a new formalism of type-logical grammars. They are weakly equivalent to context-free grammars [8]. The proof in one direction uses the fact that context-free languages are closed under homomorphism and inverse homomorphism. Here we present a direct construction of a context-free grammar and a push-down automaton, equivalent to a given pregroup grammar. The size of the resulting contextfree grammar (push-down automaton) is polynomial in the… Expand
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