Effects of objective and subjective task complexity on performance

The thesis of this research is that performance on a task depends not only on objective complexity (a task characteristic) but also on one's perception of task complexity. This study allowed investigation of the influences of (a) cognitive ability, (b) motivation, (c) subjective task complexity, and (d) task experience on performance for an objectively simple or complex scheduling task. Potential determinants of subjective complexity were also studied, as well as the mediating effects of subjective complexity on the relations between independent variables (i.e., objective complexity, cognitive ability, and task experience) and task performance. Participants (N= 195) were undergraduates who prepared a 1-week work schedule for a fictitious film processing store under either a Simple or Complex condition. Those in the Complex condition were additionally required to account for employee ''time off'' and varying store traffic. Hierarchical regression revealed significant, unique main effects for objective task complexity and subjective task complexity in predicting task performance when controlling for cognitive ability. Subjective task complexity was found to partially mediate the (a) objective task complexity-performance and (b) cognitive ability-performance relations. Future directions for research and theory are discussed.