Evaluating rater judgments on ETIC Advanced writing tasks: An application of generalizability theory and Many-Facets Rasch Model
Jiayu Wang & Kaizhou Luo, National Research Centre for Foreign Language Education, Beijing Foreign Studies University, China
Volume 8, Issue 2, 2019
Abstract: Developed by China Language Assessment (CLA), the English Test for International Communication Advanced (ETIC Advanced) assesses one’s ability to perform English language tasks in international workplace contexts. ETIC Advanced is only composed of writing and speaking tasks, featured with authentic constructed response format. However, the elicitation of extended responses from candidates would call for human raters to make judgments, thus raising a critical issue of rating quality. This study aimed to evaluate rater judgements on the writing tasks of ETIC Advanced. Data in the study represented scores from 186 candidates who performed all writing tasks: Letter Writing, Report Writing, and Proposal Writing (n=3,348 ratings). Rating was conducted by six certified raters based on a six-point three-category analytical rating scale. Generalizability theory (GT) and Many-Facets Rasch Model (MFRM) were applied to analyse the scores from different perspectives. Results from GT indicated that raters’ inconsistency and interaction with other aspects resulted in a relatively low proportion of overall score variance, and that the ratings sufficed for generalization. MFRM analysis revealed that the six raters differed significantly in severity, yet remained consistent in their own judgements. Bias analyses indicated that the raters tended to assign more biased scores to low-proficient candidates and the Content category of rating scale. The study serves to demonstrate the use of both GT and MFRM to evaluate rater judgments on language performance tests. The findings of this study have implications for ETIC rater training.
Keywords: ETIC Advanced, rater judgements, generalizability theory, Many-Facets Rasch Model