Testing two classes of theories about group induced shifts in individual choice

Abstract

One class of theories explains group induced shifts in individual choice in terms of interpersonal comparison process. By comparing himself with others a member finds out that his position is uncomfortably discrepant, e.g., he is overly cautious or overly risky. Knowledge of this discrepancy presumably is necessary and sufficient to induce him to change his initial choice. Another class of theories holds that merely knowing one is different from others is unimportant. Shifts in choice occur because during discussion a member is exposed to persuasive arguments which prior to discussion were not available to him. Two experiments were conducted, the results of which give considerable support to persuasive-argument theories and none to those based on interpersonal comparison: When a member did not know whether others were arguing for their own position or were forced to support a position contrary to the one they had originally chosen, and the former in fact was the case, typical shifts in choice were obtained. However, if a member had to argue for a position contrary to the one he had initially chosen (and thus he would not be able to muster highly persuasive arguments) typical shifts did not occur, even though another's initial choice could be accurately inferred.