An investigation into rater performance with a holistic scale and a binary, analytic scale on an ESL writing placement test

Abstract

This two-phased, sequential mixed-methods study investigates how raters are influenced by different rating scales on a college-level English as a second language (ESL) writing placement test. In Phase I, nine certified raters rated 152 essays using a holistic, profile-based scale; in Phase II, they rated 200 essays using a binary, analytic scale developed based on the holistic scale and 100 essays using both rating scales. Ratings were examined both quantitatively through Rasch modeling and qualitatively via think-aloud protocols and semi-structured interviews. Findings from Phase I revealed that, despite satisfactory internal consistency, the raters demonstrated relatively low rater agreement and individual differences in their use of the holistic scale. Findings from Phase II showed that the binary, analytic scale led to much improvement in rater consensus and rater consistency. Another finding from Phase II suggests that the binary, analytic scale helped the raters deconstruct the holistic scale, reducing their cognitive burden. This study represents a creative use of a binary, analytic scale to guide raters through a holistic rating scale. Implications regarding how a rating scale affects rating behavior and performance are discussed.