Application of the Graded Response Model of Item Response Theory to Computerized Dynamic Assessment in L2 English Education

Abstract

The purposes of this paper are to (a) develop an adaptive system with the help of the graded response model of IRT, (b) test the system with a small group of L2 learners, (c) examine the feasibility of computerized dynamic assessment, and (d) propose a new set of scoring mechanisms. We developed a computer-based adaptive system that provides students with appropriate test items and a set of graduated prompts from implicit to explicit under the conditions of mediation. We found that the set of graduated prompts successfully guided students to the correct answer and provided rich diagnostic information needed for L2 English education. With the help of the graded response model of IRT, computerized dynamic assessment will become a more advanced and practical educational assessment tool in the field of L2 studies.