Date of Award

Spring 1993

Project Type


Program or Major


Degree Name

Doctor of Philosophy

First Advisor

Victor A Benassi


This dissertation examines the effects of self-efficacy and group size on the judgments of control of individual subjects in a group situation. It was predicted that highly efficacious subjects would report more judged control, inefficacious subjects would report less judged control. Group size was predicted to affect judgments of control in a manner consistent with the social loafing and social facilitation literature, such that individually unidentifiable subjects should "loaf" and report less control. Individually identifiable subjects should find their prior efficacy beliefs facilitated, such that high believers feel increasing control with increasing group size and low believers feel decreasing control with increasing group size. Experiment 1 measured subjects' judged control over the outcome of a die toss in a situation designed to engender social loafing (subjects' output was indistinguishable from that of other group members). Prior belief in psi abilities reliably predicted judged control, but group size was not a significant predictor. Neither prior belief nor group size significantly affected judged own or other effort. Experiment 2 measured subjects' judged control over a die toss in a situation designed to produce social facilitation (subjects' output was individually identifiable). Prior belief in psi abilities reliably predicted judged control; group size was positively related to judged group control, but not to individual measures of control or to effort. Results were consistent with previous literature in self-efficacy, and somewhat consistent with loafing and facilitation research.