A personality orientation characterized either by the belief that one can control events by one's own efforts (internal locus of control) or that the future is determined by forces outside one's control (external locus of control).

If a person with an internal locus of control does badly on a test, she is likely to blame either her own lack of ability or preparation for the test. By comparison, a person with an external locus of control will tend to explain a low grade by saying that the test was too hard or that the teacher graded unfairly. The concept of locus of control was developed by psychologist Julian Rotter, who devised the Internal-External Locus of Control Scale (I-E) to assess this dimension of personality. Studies have found that this test is a valid predictor of behavior typically associated with locus of...