ANOTHER LOOK AT REASONING EXPERIMENTS - RATIONALITY, NORMATIVE MODELSAND CONVERSATIONAL FACTORS

In many studies, human reasoning has been depicted as ''biased'' or de viating from normative models in both areas of deductive and inductive reasoning. Two criteria for evaluation of reasoning studies are propo sed in this paper. The first criterion concerns the selection and appl ication of normative models against which human performance is assesse d. The second criterion concerns the role of conversational factors in the differential selection of information used in the subsequent judg ment. These two criteria were applied to studies on two tasks from the fields of deductive and inductive resaoning, the Wason selection task and the base rate fallacy. In view of alternative normative systems, control of the application of the normative models used and the percei ved conversational relevance of the information presented in the exper imental tasks, the alleged biases have been demonstrated to be largely unsupported. The analysis is consistent with the notion that human re asoning is optimal and rational. The implications of the present accou nt for reasoning experiments are discussed.