Statistical reasoning in novices

There is a growing body of evidence indicating that people often overestimate the similarity between characteristics of random samples and those of the populations from which they are drawn. In the first section of the paper, we review some studies that have attempted to determine whether the basic heuristic employed in thinking about random samples is passive and descriptive or whether it is deducible from a belief in active balancing. In the second section, we discuss the importance of sample size on judgments about the characteristics of random samples.