LAUSR

Abstract Diversity-based reasoning (DBR), the tendency to generalize from diverse samples rather than homogenous samples, is a hallmark of sophisticated inductive reasoning. However, the developmental origins of DBR remain unclear. Results from the studies reported in this paper reveal that the method by which evidence is presented plays an integral role in determining whether preschoolers (N = 117, Mage = 4;4, range 3;11–5;2) engage in DBR. In a sample comparison task (Experiments 1b and 3), young children engaged in DBR when evidence exemplars were presented sequentially, but not when these same exemplars were presented simultaneously. Experiment 1a revealed a similar effect of presentation format on adults (N = 40, Mage = 21;2). Performance across several manipulations indicates that these presentation effects are robust in children. Children generalized from diverse samples whether the contents of samples included biological properties of animals (Experiment 1) or the preferences of social actors (Experiment 2). Also, the effect remained when the inductive problem involved generalization from a single sample (Experiment 3). Overall, these results indicate that diversity-based reasoning is utilized early in development and is facilitated by specific task features that govern the processes used to make inductive generalizations.