Polynomial Learnability and Locality of Formal Grammars

Abstract

We apply a complexity theoretic notion of feasible learnability called polynomial learnability to the evaluation of grammatical formalisms for linguistic description. We show that a novel, nontrivial constraint on the degree of locality of grammars allows not only context free languages but also a rich class of mildly context sensitive languages to be polynomially learnable. We discuss possible implications of this result to the theory of natural language acquisition