Exemplar-theoretic integration of phonetics and phonology: Detecting prominence categories in phonetic space

This article explores an exemplar-theoretic approach to the integration of phonetics and phonology in the prosodic domain. In an exemplar-theoretic perspective, prominence categories, here specifically, pitch-accented syllables and unaccented syllables, are assumed to correspond to accumulations of similar exemplars in an appropriate perceptual space. It should then be possible, as suggested for instance by Pierrehumbert (2003), to infer the (phonological) prominence categories by clustering speech data in this (phonetic) space, thus modeling acquisition of prominence categories according to an exemplar-theoretic account. The present article explores this approach on one American English and two German databases. The experiments extend an earlier study (Schweitzer, 2011) by assuming more acoustic-prosodic dimensions, by excluding higher-linguistic or phonological dimensions, and by suggesting a procedure that adjusts the space for clustering by modeling the perceptual relevance of these dimensions relative to each other. The procedure employs linear weights derived from a linear regression model trained to predict categorical distances between prominence categories from phonetic distances using prosodically labeled speech data. It is shown that clusterings obtained after adjusting the perceptual space in this way exhibit a better cluster-to-category correspondence that is comparable to the one found for vowels, and that both the detection of vowel categories and the detection...
Source: Journal of Phonetics - Category: Speech-Language Pathology Source Type: research