Sensitivity to alternatives in social hypothesis-testing ☆

Abstract Past research has documented a hypothesis-testing strategy wherein evidence is sought to the extent that it is probable under the hypothesis. This strategy may yield nondiagnostic information and even biased confirmation of the hypothesis if the simultaneous probability of the evidence under the alternatives is disregarded. The results of three experiments demonstrated that hypothesis-testers were in fact sensitive to the probability of the evidence under the alternatives. In the first experiment, subjects tested a hypothesis under which two kinds of personal features, A-features and B-features, were highly probable. Subjects could test their hypothesis by selecting questions from a list of questions about A-features and B-features. The rerults showed that subjects' questions depended on the probability of the features under the alternative. Specifically, when the hypothesis shared A-features with the alternative, subjects preferred questions about B-features, but when the hypothesis shared B-features with the alternative, subjects preferred questions about A-features. Experiment 2 extended these findings to self-generated questions about a broader range of hypotheses and alternatives. Experiment 3 found that subjects who were provided with a specific alternative asked more diagnostic questions than subjects who were not provided with a specific alternative. Together, these results suggest that the process of generating and evaluating alternatives plays a crucial role in social hypothesis-testing and categorization.