New consonantal acoustic parameters for forensic speaker comparison

This thesis examines acoustic parameters of five consonants /m, n, ŋ, l, s/ in two dialects of British English: Standard Southern British English and Leeds English. The research aims to explore population distributions of the acoustic features, gauge cross-dialectal variation, and discover new parameters for application in forensic speaker comparison casework. The five parameters investigated for each segment are:

For /m, n, ŋ, l/:
Normalised duration, Centre of gravity, Standard deviation, Frequency at peak amplitude, Frequency at minimum amplitude

For /s/: Normalised duration, Centre of gravity, Standard deviation, Skewness, Kurtosis

The work contributes firstly to the general phonetic literature by presenting acoustic data for a number of parameters and consonant segments that have not been previously studied in depth in these dialects. Secondly, the research informs the forensic phonetic literature by considering the intra- and inter-speaker variability and gauging the relative speaker-specificity of each acoustic feature. Discriminant analysis and likelihood ratio estimation assess the discrimination ability of each feature, and results highlight several promising parameters with potential for application in forensic speaker comparison casework.