Interpreting the phonetic variation of discourse features for applications

Speaker: Dr. Ben Gibb-Reid

Abstract:

Forensic speaker comparison (FSC) analysis often involves segmental and suprasegmental variables, but phonetic variation at the word level is something that has been little explored. As there is no guarantee that multiple forensic recordings will share the same features, the most frequently-used words in speech may be of value to the FVC practitioner. This research presents analyses of two of the most frequent words in British English (yeah and just). The work assesses the speaker discriminant capability of various acoustic estimates taken from these markers. It also establishes a link between pragmatic functions/context and phonetic realisation which causes yeah to have a very high level of within-speaker variation. Overall, this indicates that words with multiple discourse functions (such as yeah and like) are best analysed as a collection of multiple lexical items rather than as one ‘feature’ in FSC casework. Just however is a promising speaker discriminant with a range of facets which lend itself well to acoustic estimates.