The “Law of Small Numbers”: An Unexpected and Incidental Replication

Summary

Thirty-seven graduate students in nursing were given the problem set, used by Tversky and Kahneman in their study on the “law of small numbers,” as an extra credit part of a final examination for a statistics course. While some conservativism was noted, the major Tversky and Kahneman postulates were supported. These incidentally obtained replication data provide support for the contention that the tendency, induced by representativeness, to confidently make inferences is only slightly, if at all, determined by factors such as statistical and empirical sophistication, availability of normative criteria, knowledge about the shortcomings of human judgment, and the conditions under which inferences are to be made.