How can We Explain Biases Observed in the Solution of the Indicative Wason Selection Task?

Abstract

Each of some promising theories explains human performances on the indicative Wason selection task. For example, participants usually select the 5 case, in the selection task with the conditional “if an E, then a not-5”. This tendency of the selection was explained by the heuristic-analytic theory, which is one of the dual-processing theories, that people are likely to regard a matching case as relevant to the truth of the conditional in the heuristic process (Evans, 1998). However, because a positive concept constructs a smaller set than its negative one does (a rarity assumption), it is more effective to get information on the truth of the conditional in a positive set than in a negative set. Thus the optimal data selection theories can also explain the effect. Yama (2001) found that the so-called matching bias was an amalgam of two different cognitive components, namely, relevance judgment by matching and the optimal data selection process. It was examined if the dual-processing theories captured the optimal data selection process with some evidences and concluded that, although the heuristic-analytic theory should be revised, the implication of the evidences could be discussed within the framework of the dual-processing theories.