Predictive validity considerations in selection dictate choice of the predictor with the highest predictive validity. Implementation of this principle in any specific selection process inevitably entails choice between imperfectly correlated alternative predictors, real or hypothetical, which are equivalent in terms of predictive validity. We show…

Selection to programmes for gifted students in Israel, performed in the second grade, relies on raw ability and achievement test scores, irrespective of age, thereby ignoring the well-known effect of within-grade age differences on test scores. Employing the entire cohort of third graders of legal age (67,366 students, 1.4% of whom were enrolled…

Fiedler and Kareev (2006) showed that small samples can, in principle, outperform large samples in terms of the quality of contingency-based binary choice. The 1st part of this comment critically examines these authors' claim that this small sample advantage (SSA) contradicts Bernoulli's law of large numbers and concludes that this claim is…

Proposed a definition of selection bias and studied the empirical relation between prediction bias and selection bias with respect to prominent social groups. Results show that, although the two biases are related, the relation is not isomorphic. It is mediated by the selection ratio, and for most selection ratios, it is only moderate. (SLD)