Computer Adaptive Testing Using the Same-Decision Probability

Computer Adaptive Tests dynamically allocate questions to students based on their previous responses. This involves several challenges, such as determining when the test should terminate, as well as which questions should be asked. In this paper, we introduce a Computer Adaptive Test that uses a Bayesian network as the underlying model. Additionally, we show how the notion of the Same-Decision Probability can be used as an information gathering criterion in this context — to determine which further questions are needed and if so, which further questions should be asked. We show empirically that utilizing the Same-Decision Probability is a viable and intuitive approach for determining question selection in Bayesian-based Computer Adaptive Tests, as its usage allows us to ask fewer questions while still maintaining the same level of precision and recall in terms of classifying competent students.