Cross-entropic comparison of formants of British, Australian and American English accents

This paper highlights the differences in spectral features between British, Australian and American English accents and applies the cross-entropy information measure for comparative quantification of the impacts of the variations of accents, speaker groups and recordings on the probability models of spectral features of phonetic units of speech. Comparison of the cross entropies of formants and cepstrum features indicates that formants are a better indicator of accents. In particular it appears that the measurements of differences in formants across accents are less sensitive to different recordings or databases compared to cepstrum features. It is found that the cross entropies of the same phonemes across speaker groups with different accents (inter-accent distances) are significantly greater than the cross entropies of the same phonemes across speaker groups of the same accent (intra-accent distances). Comparative evaluations presented on cross-gender speech recognition shows that accent differences have an impact comparable to gender differences. The cross entropy measure is also used to construct cross-accent phonetic trees, which serve to show the structural similarities and differences of the phonetic systems across accents.