Explanation or Modeling: a Reply to Kellen and Klauer

Abstract

AbstractIn Wason’s “selection” task, individuals often overlook potential counterexamples in selecting evidence to test hypotheses. Our recent meta-analysis of 228 experiments corroborated the main predictions of the task’s original theory, which aimed to explain the testing of hypotheses. Our meta-analysis also eliminated all but 1 of the 15 later theories. The one survivor was the inference-guessing theory of Klauer et al., but it uses more free parameters to model the data. Kellen and Klauer (this issue) dissent. They defend the goal of a model of the frequencies of all 16 possible selections in Wason’s task, including “guesses” that occur less often than chance, such as not selecting any evidence. But an explanation of hypothesis testing is not much advanced by modeling such guesses with independent free parameters. The task’s original theory implies that individuals tend to choose items of evidence that are dependent on one another, and the inference-guessing theory concurs for those selections that are inferred. Kellen and Klauer argue against correlations as a way to assess dependencies. But our meta-analysis did not use them; it used Shannon’s measure of information to establish dependencies. Their modeling goal has led them to defend a “purposely vague” theory. Our explanatory goal has led us to defend a “purposely clear” algorithm and to retrieve long-standing evidence that refutes the inference-guessing theory. Individuals can be rational in testing a hypothesis: in repeated tests, they search for some examples of it, and then exhaustively for counterexamples.