Xian LiFollow

Date of Award

Summer 8-8-2024

Degree Type


Degree Name

Doctor of Philosophy (PhD)


Applied Linguistics and English as a Second Language

First Advisor

Sara Cushing

Second Advisor

YouJin Kim

Third Advisor

Shuai Li

Fourth Advisor

Stephanie Lindemann


One of the key attributes of effective oral communication is the ability to engage in and maintain spoken interaction, or Interactional Competence (IC). While humans are familiar with this ability because we experience interactions frequently, how to assess an individual’s IC in oral communication, especially in an additional language (L2), has been met with many challenges. Researchers have debated over what rating criteria and task types are most appropriate for IC assessment, especially with the rise of digital assessment tools. In light of these challenges, this dissertation study investigates the construct of L2 interactional competence and explores spoken interactions in a local, video-mediated speaking test. In particular, this study examines the effect of task types (i.e., individual interview or paired discussion) on test scores and explores the perspectives of linguistic layperson (i.e., nonexpert) raters to understand salient features in a video-mediated test. Testing data came from videos of 24 international students who completed both an individual interview and a paired discussion task in a local university placement test on Zoom. Four expert raters evaluated all examinees’ performances using an analytical rubric that included the following criteria: (1) Pronunciation & fluency, (2) Grammar & vocabulary, (3) Turn management, (4) Topic management, (5) Engagement with interaction, and (6) Nonverbal features. A total of 144 layperson raters evaluated examinees’ overall communication skill, providing a numerical holistic score and explaining their rationale in written comments. The results from Many-facets Rasch Measurement (MFRM) revealed that paired discussion tasks yielded lower scores in oral communication skill scores from both expert and layperson ratings. The results from written comments revealed that layperson raters paid more attention to linguistic features such as fluency and pronunciation during their ratings. Nonlinguistic features such as confidence and nonverbal behaviors were also found to be important in their evaluation of oral communication skill. This study sheds light on the construct of interactional competence and the evaluation of oral communication skill, highlighting the need to incorporate nonlinguistic features into L2 speaking assessment. The exploration of an online speaking test also contributes validity evidence to language assessment in online environments.


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