Quantitative assessment of English accent variation: Levenshtein distance and perceptual identification

This is a perceptual study with a basis in acoustic phonetics. It investigates the extent to which accents of English can be quantified by the Levenshtein distance (LD), a string metric. LD defines string similarity by the minimum number of character edits required to transform one string into another. Narrowly transcribed speech samples of English provide the phonetic strings required for LD comparison. For the purposes of the current experiment, 24 speakers representing four English accent varieties are included: Midland American (control), British/Australian, Hindi-influenced, and Mandarin-influenced. High- and low-pass filters are used to augment or attenuate perceptual contribution of high- versus low-frequency information in the speech signal. Predictions stem from published correlations between LD and listeners’ perceptional ratings of intelligibility and native-likeness. For a group of monolingual American English listeners, confusion is expected between Midland American and British/Australian accents due to similarly low LDs, further intensified by low-pass filtering. However, fewer confusions are predicted between Hindi- and Mandarin-influenced English, due to varying L1 influences and the absence/presence of tonal information. This research seeks to explore accent perception, investigating the relationship between manipulated aspects of the speech signal and listener identification.