tailieunhanh - Báo cáo khoa học: "TOWARD A COMPUTATIONAL THEORY OF SPEECH PERCEPTION "

In recent years,a great deal of evidence has been collected which gives substantially increased insight into the nature of human speech perception. It is the author's belief that such data can be effectively used to infer much of the structure of a practical speech recognition system. This paper details a new view of the role of structural constraints within the several structural domains (. articulation, phonetics, phonology, syntax, semantics) that must be utilized to infer the desired percept. . | TOWARD A COMPUTATIONAL THEORY OF SPEECH PERCEPTION Jonathan Allen Research Laboratory of Electronics Dept of Electrical Engineering and Computer Science Massachusetts Institute of Technology Cambridge MA 02139 ABSTRACT In recent years a great deal of evidence has been collected which gives substantially increased insight Into the nature of human speech perception. It is the author s belief that such data can be effectively used to Infer much of the structure of a practical speech recognition system. This paper details a new view of the role of structural constraints within the several structural domains . articulation phonetics phonology syntax semantics that must be utilized to Infer the desired percept. Each of the structural domains mentioned above has a substantial internal theory describing the constraints within that domain but there are also many Interactions between structural domains which must be considered. Thus words like Incline and survey shift stress with syntactic role and there Is a pragmatic bias for the ambiguous sentence John called the boy who has smashed his car up. to be Interpreted under a strategy that reflects a tendency for local completion of syntactic structures. It Is clear then chat while analysis within a structural domain . syntactic parsing can be performed up to a point interaction with other domains and integration of constraint strengths across these domains Is needed for correct perception. The various constraints have differing and changing strengths at different points in an utterance so that no fixed metric can be used to determine their contribution to the well-formedness of the utterance. At the segmental level many diverse cues for segmental features have been found. As many as 16 cues mark the voicing distinction for example. We may think of each of these cues as also representing a constraint and the strength of the constraint varies with the context. For example stop closure duration must be Interpreted In the .