Abstract
This study focuses on the impact of individual differences in intellectual ability and motivation on venture performance. Intellectual ability of entrepreneurs was tested by an intelligence test taken earlier during the enlistment test of the national service in Sweden. The proposed model took into account the mutual influence between the environment and the entrepreneurs. Performance was measured as business efficiency and ability to grow. The findings suggest that intellectual ability as measured by IQ has little impact on business performance, but the mean of intelligence was above the population mean. However, ability measures related to the understanding of task requirements were positively related to performance. The entrepreneurs' persistence and job interests discriminated between better and poorer performance. The most important environment variable was the market structure.