A self-rating scale of English difficulty: Rasch scalar analysis of items and rating categories

This study has sought to demonstrate the utility of Rasch Model scalar analysis when applied to self-ratings of ability/difficulty associated with component skills of English as a second language. Eleven skill areas were rated for difficulty on a seven-point Likert-type scale by 228 ESL students at the University of California. Following appropriate tests of unidimen sionality, both skill area items and rating categories were calibrated for difficulty, examined for fit to the Rasch Model, and plotted to provide visual representation of the nature of the item characteristic curves. Specific suggestions were made for the improvement of the rating cate gories of the self-rating scale, and skill areas most susceptible to self- rating error were identified. It was concluded that scalar analysis of the kind considered here is feasible with self-rating data, and that other rating scale procedures such as those employed. to rate proficiency in foreign language speaking or writing would probably benefit from similar scalar analyses.