Executive SummaryThe aim of this study was twofold: First, we investigated whether scores on an admission test lead to similar predictions in future study success when administered in a proctored-and an unproctored setting. Second, we explored how Bayesian modeling can be of help in interpreting admission-testing data. Results showed that the mode of administration of an admission test did not result in different models for predicting study success and that Bayesian modeling provide a very useful-and easy-to-interpret framework for predicting the probability of future study success.
3Arguably the most important aim of admission testing is the prediction of future academic success. Academic success is typically operationalized as GPA or study progress, but can also include leadership or citizenship (e.g., Stemler, 2012;Sternberg, 2010). In order to accept those students with the highest academic potential, students are admitted to college or graduate programs based on admission criteria such as scores on admission tests and other possible predictors such as high school performance (in the case of undergraduate admissions), undergraduate performance (in the case of graduate school admissions), biodata (such as life and work experience), personal statements, recommendations, and interviews (Clinedinst & Patel, 2018). Since access to higher education programs is an important determinant of later life outcomes, such as income, attitudes, and political behavior (Lemann, 1999, p. 6), it is important that admission procedures consist of fair and valid instruments and procedures.The widespread use of computers further allows for more varied forms of assessment, which makes admission testing even more difficult. Testing at a distance is now more common, although it does raise questions concerning the validity of the test results. Dishonest testing behavior (e.g., cheating) is more difficult to control in unproctored, online, tests. Furthermore, the security of test items is also potentially jeopardized, which may contribute to inflated test scores. Hence, it is crucial to ascertain that test takers who are assessed at a distance (i.e., unproctored) are not advantaged over test takers who are assessed in a proctored environment. In this study we investigate whether proctored and unproctored tests may lead to different test results, and to differences in prediction, which is of major importance in admission testing. If unproctored test-takers engage in cheating, we would expect that their academic performance is overpredicted, that is, they perform less well academically 4 than we would expect based on their admission test scores. We study differential prediction between unproctored and proctored test using real admission test data.Specifically, we compare scores across the two groups by means of the moderated multiple regression model proposed by Lautenschlager and Mendoza (1986), under both the frequentist and the Bayesian paradigm. Our goal is to investigate whether differential prediction of first year GPA exists betwe...