Estimates of Speech Efficiency in Monolingual and Bilingual Speakers of English

Folia Phoniatr Logop. 2024 Jul 31:1-10. doi: 10.1159/000540671. Online ahead of print.

Abstract

Introduction: The Speech Efficiency Score (SES) serves as an acoustic metric for assessing fluency in conversational speech within the temporal domain. This study leverages SES to investigate conversational speech efficiency among native speakers of American English (AE) compared to speakers of Mandarin-accented English (MAE).

Methods: SES, speaking rate, articulation rate, and vocabulary diversity were measured and compared between two groups: native AE speakers and MAE speakers. The study utilized conversational speech samples collected from both groups to analyze these metrics.

Results: Findings indicate a disparity in speaking rate and articulation rate between the AE and MAE groups, with the AE group exhibiting significantly faster speech. However, no significant differences were observed in SES and vocabulary diversity between the two groups.

Conclusion: The results are discussed in the context of the interplay between speaking rate, speech fluency, and vocabulary diversity. These findings shed light on the maintenance of speech efficiency among bilingual speakers, suggesting that despite differences in speaking rate and articulation rate, SES and vocabulary diversity remain comparable between native AE speakers and MAE speakers.

Keywords: L2 English; Mandarin-English bilingual; Speech efficiency score; Type-token ratio; Vocabulary diversity.