Unfamiliar accents can cause word recognition challenges, particularly in noisy environments, but few studies have incorporated quantitative pronunciation distance metrics to explain intelligibility differences across accents. To address this gap, intelligibility was measured for 18 talkers -- two from each of three first-language, one bilingual, and five second-language accents -- in quiet and two noise conditions. The relations between two edit distance metrics, which quantify phonetic differences from a reference accent, and intelligibility scores were assessed. Intelligibility was quantified through both fuzzy string matching and percent words correct. Both edit distance metrics were significantly related to intelligibility scores; a heuristic edit distance metric was the best predictor of intelligibility for both scoring methods. Further, there were stronger effects of edit distance as the listening condition increased in difficulty. Talker accent also contributed substantially to intelligibility models, but relations between accent and edit distance did not consistently pattern for the two talkers representing each accent. Frequency of production differences in vowels and consonants was negatively correlated with intelligibility, particularly for consonants. Together, these results suggest that significant amounts of variability in intelligibility across accents can be predicted by phonetic differences from the listener’s home accent. However, talker- and accent-specific pronunciation features, including suprasegmental characteristics, must be quantified to fully explain intelligibility across talkers and listening conditions.
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Predicting intelligibility from pronunciation distance metrics
Unfamiliar native and non-native accents can cause word recognition challenges, particularly in noisy environments, but few studies have incorporated quantitative pronunciation distance metrics to explain intelligibility differences across accents. Here, intelligibility was measured for 18 talkers -- two from each of three native, one bilingual, and five non- native accents -- in three listening conditions (quiet and two noise conditions). Two variations of the Levenshtein pronunciation distance metric, which quantifies phonemic differences from a reference accent, were assessed for their ability to predict intelligibility. An unweighted Levenshtein distance metric was the best intelligibility predictor; talker accent further predicted performance. Accuracy did not fall along a native - non-native divide. Thus, phonemic differences from the listener’s home accent primarily determine intelligibility, but other accent- specific pronunciation features, including suprasegmental characteristics, must be quantified to fully explain intelligibility across talkers and listening conditions. These results have implications for pedagogical practices and speech perception theories.
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- Award ID(s):
- 1941691
- PAR ID:
- 10491960
- Editor(s):
- Radek Skarnitzl & Jan Volín
- Publisher / Repository:
- Guarant International
- Date Published:
- ISBN:
- 978-80-908-114-2-3
- Subject(s) / Keyword(s):
- Speech perception intelligibility non-native accents regional accents
- Format(s):
- Medium: X
- Location:
- Prague, Czech Republic
- Sponsoring Org:
- National Science Foundation
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