Multi-Speaker Experiments with the Morphic Generator Grammatical Inference Methodology

Abstract

Grammatical Inference (GI) is the learning or model estimation phase required by any Syntactic approach to Pattern Recognition (PR). Some fundamental results on GI have been known since the 60’s through the works by Gold (1967) and Feldman (1972), which stablished that the decidability of any (even regular) GI problem depends largely upon the avaibility of both an adequate positive sample R+ of strings known to have been generated by the unknown Grammar, and an equally adequate negative sample R- of strings not generated by that Grammar. Despite these results being commonly recognized, taking into account negative samples, lead, in general to intractable GI problems (see /Angluin,78/) and, consequently, most recent works on GI only use positive samples, an aim just at giving practical solutions to specific PR problems (see eg. /Angluin,83/ /Fu,75/). Clearly, this paradigm is not a very appealing one, and some general methodology seems to be strongly required.

Work supported in part by the Spanish CAICYT under grant PA85-86.