Abstract

This study was performed to examine the relative validity of the single process model and the dual process model in majority and minority influences through a survey research and an experimental studty. We hypothesized, based upon the dual process model, that majority and minority influences are moderated by the level of situational uncertainty and types of responses(public/private responses). In the survey 180 college students were asked to write plausible situational, behavioral and causal explanations about majority and monority influences under the certain or uncertain outcome conditions. In the experiment 112 subjects were randomly assigned to 8 conditions with 3 way factorial design, ie., certain/uncertain task situation(2) ×source size(4) ×public and private response with repeated measure(2). The results revealed that the majority had stronger mormative and informational influences compared to the equal size source or minority, especially under the uncertain task conditions. The results also showed a significant influence of minority on the private response under the uncertain task conditions. We interpreted the results as a supportive evidence for the dual process model, and discussed some unsolved issues in this study for further study.