How to Split Re ursive Automata
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How to Split Re ursive Automata Isabelle Tellier LIFL - Inria Lille Nord Europe university of Lille isabelle.tellieruniv-lille3.fr ?? In this paper, we interpret in terms of operations applying on extended nite state automata some algorithms that have been spe ied on ategorial grammars to learn sub lasses of ontext-free languages. The algorithms onsidered imple- ment spe ialization strategies. This new perspe tive also helps to understand how it is possible to ontrol the ombinatorial explosion that spe ialization te hniques have to fa e, thanks to a typing approa h. 1 Introdu tion There are often several ways to represent a language: it is well known that every regular language an be spe ied either by a regular grammar or by a deter- ministi nite state automaton. Context-free languages an also be spe ied by dierent kinds of devi es. In re ent previous papers [17, 18?, we have shown that some lasses of ategorial grammars (CGs in the following), generating ontext- free languages, ould easily be represented by a family of extended automata alled re ursive automata (RA). This translation allowed to exhibit onnexions between two previously distin t approa hes of grammati al inferen e from posi- tive examples: the one used in [3, 13, 14? to learn CGs, and the one used to learn regular grammars represented by nite state automata [1, 10?.
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