Natural Languages And The Chomsky Hierarchy
نویسنده
چکیده
The central claim of the paper is that NL stringsets are regular. Three independent arguments are offered in favor of this position: one based on parsimony considerations, one employing the McCullogh-Pitts (1943) model of neurons, and a purely linguistic one. It is possible to derive explicit upper bounds for the number of (live) states in NL acceptors: the results show that finite state NL parsers can be implemented on presentday computers. The position of NL stringsets within the regular family is also investigated: it is proved that NLs are counter-free, but not locally testable.
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تاریخ انتشار 1985