Repeat individualized assessment using isomorphic questions: a novel approach to increase peer discussion and learning

It is demonstrated that the fully automatic generation of isomorphic questions allows for both repeat assessment, and for this assessment to be individualized. While this does require a substantial up-front effort, once prepared assessments can be reproduced with relative ease and with a near-zero probability of students receiving the same question a second time. We show the effectiveness of this approach using survey and performance data obtained from large year 2 and year 3 computer science classes. A greater than 10-fold increase in online peer discussion was observed, compared to the previous year. Contents analysis of the surveys showed that repeat testing was generally regarded favourably. Quantitative analyses found that prior homework did little to improve initial test performance, but was of vital importance in studying for the follow-up isomorphic test. Moreover, the performance gain on the isomorphic questions was the same for all students regardless of their overall ability, and was retained in the final exam.