Processing the information contained in another's behavior

This study investigates attributions based on behavior congruent with situational demands (in-role) and those based on behavior incongruent with situational demands (out-of-role). By analyzing these processes in terms of a Bayesian inference model, it was possible to determine (a) the diagnostic values observers intially assign to behaviors, (b) the actual informational impact of these behaviors, and (c) the degree of optimality in processing information contained therein. The main results can be summarized as follows: (1) The diagnostic value and actual informational impact of out-of-role behaviors were much higher than those of inrole behaviors. (2) Information about out-of-role behaviors was less optimally processed than information about in-role behaviors. (3) Observers assigned smaller diagnostic values to behaviors which were described in great detail than to behaviors which were described in summary statements. (4) Observers' attitudes influenced their initial beliefs about the actors but not the processing of new information about the actor. (5) The Bayesian inference model predicted observers' inferences reasonably well.