Norm of Internality or Hypothesis Confirmation Bias? An Experimental Approach to the Construction of Internality Questionnaires

Résumé 0

This research tests the hypothesis of a confirmation bias in the current procedure of internality questionnaires. In a pilot study, 18 students produced explanations for the construction of a questionnaire of internality with knowledge of the existence of a norm of internality vs. externality, or without prior activation of such knowledge (control condition). In a first study, 32 students evaluated the locus of causality and the plausibility of the explanations produced in the pilot study. In a second study, 113 students assessed the social value of these explanations in a situation of recruitment. The results indicate first that the confirmation bias influences individuals when they were asked to produce internal and external explanations. We thus observed that the difference between internal and external explanations on plausibility (Study 1) and on social value (Study 2) was more in favor of internal explanations in the internality norm condition than in the control condition. Moreover, the difference between internal and external explanations on both measures were more in favor of internal explanations in the control condition than in the externality norm condition. In addition, the results obtained in the control condition suggest that internal explanations are more plausible (Study 1) and more valued than external explanations (Study 2). These studies reveal the impact of the confirmation bias, and suggest the existence of a norm of internality in social thought.