
Investigating the Impact of Interlocutor Type on English Oral Proficiency Interviews: A Comparative Analysis of Chatbot and Human Interlocutors
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Abstract
Considering the recent emergence of voice chatbots as substitutes for human interlocutors in eliciting spoken responses during English oral proficiency interviews, this study examines how interlocutor type affects both fluency and holistic scores. Data were collected from 32 Korean college students, yielding 128 audio recordings across four distinct topics of varying complexity, with each topic administered via both chatbot and human interlocutors. Fluency features were analyzed using Praat software, while fluency and holistic scores were evaluated via many-facet Rasch measurement (MFRM) analyses by two raters. Results from Friedman and Wilcoxon tests indicate that both task complexity and interlocutor type influence temporal measures, although task complexity exerts a stronger effect on dysfluency measures. MFRM analyses further show that chatbot interlocutor difficulty significantly affects fluency but not holistic scoring, indicating distinct difficulty levels between interlocutors only in fluency scoring. Overall, these findings highlight both the potential and limitations of employing chatbot interlocutors in place of human interlocutors in oral proficiency interviews.
Keywords:
oral proficiency interview, artificial intelligence, English as a foreign language, speaking tests, chatbotReferences
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