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Indexed Languages and Unification Grammars

Tore Burheim
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Abstract

Indexed languages are interesting in computational linguistics because they are the least class of languages in the Chomsky hierarchy that has not been shown not to be adequate to describe the string set of natural language sentences. We here define a class of unification grammars that exactly describe the class of indexed languages.

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Tore Burheim. 1995-07-24. Indexed Languages and Unification Grammars. https://arxiv.org/abs/cmp-lg/9507013

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