ABSTRACT
Statistical reasoning, sometimes called judgment under uncertainty, has received a great deal of attention in academic circles and in the media since Kahneman and Tversky’s seminal work on the subject in the early 1970s (e.g., Tversky & Kahneman, 1974). What is the reason for this unusually strong interest in psychological research results? Perhaps the interest is because the conclusions drawn have been serious: Human minds “are not built (for whatever reason) to work by the rules of probability” (Gould, 1992, p. 469). Instead, we poor “saps” and “suckers” often “stumble along ill-chosen shortcuts to reach bad conclusions” (McCormick, 1987, p. 24). In more scientific terms, people apply heuristics that lead them to biases or cognitive illusions that might have severe consequences for judgments and decisions (e.g., Arkes & Hammond, 1986; Kahneman, Slovic, & Tversky, 1982). The problem is viewed as a general one: “Quite without distinction,
politicians, generals, surgeons, and economists as much as vendors of salami and ditchdiggers are all, without being aware of it, and even when they are in the best of humors and while exercising their professions, subject to a myriad of such illusions” (Piattelli-Palmarini, 1994, p. x).
