Exploring duration and spectral parameters of English /m/ for forensic speaker comparison
Colleen Kavanagh · Proceedings of meetings on acoustics · 2013
The speaker-specificity of five acoustic features of British English /m/ was explored from a forensic speaker comparison perspective. Normalised duration, centre of gravity (COG), standard deviation (SD), and frequencies at peak and minimum amplitudes were measured for 30 adult male Standard Southern British English and Leeds English speakers. Spectral measurements were made in each of five frequency bands (0-0.5 kHz, 0.5-1 kHz, 1-2 kHz, 2-3 kHz, and 3-4 kHz) and calculated from a 40-ms window at the midpoint of each token. ANOVAs showed Speaker to be a highly significant factor for all variables. Discriminant analysis (DA) and likelihood ratio (LR) estimation assessed speaker discrimination with individual predictors and combinations thereof. Sample sizes limited the number of predictors in DA to eight; F-ratios were used to select the best predictors for analysis. The COG+SD (bands 1, 3, 4, 5) and Best 8 F-ratios (COG bands 1, 4, 5 + SD 1, 3, 4 + Peak 1, 4) tests achieved 53% and 49% correct classification respectively. The Best 8 F-ratios and COG+SD tests also produced the best LR results, while COG+Peak performed similarly. DA and LR results for all predictor combinations will be presented and the most promising speaker comparison parameters highlighted.