Evaluation of the speech behaviour of reference speakers

Abstract

In forensic settings, when speech samples have to be compared, or in LADO investigations, it is crucial to be able to differentiate the speech behavior of cooperative speakers from the speech behavior of partly cooperative speakers. In order to perform this task, a comprehensive approach which encompasses knowledge from several linguistic subfields is needed. The theoretical framework of Natural Phonology which incorporates phonetic, phonological, sociolinguistic, and psycholinguistic knowledge proves useful to perform this responsible and considerably difficult task. For illustration purposes, the analysis of three case studies will be presented. Results show that phonetic and phonological variation and process application of partly cooperative speakers differs considerably from the results generally obtained in investigations on language variation (drawn from cooperative speakers). In addition, partly cooperative speakers tend to apply substitutions which are in contradiction to phonetic and phonological principles.