Self-reports of intelligence: are they useful as proxy measures of IQ?

Correlations between single self-ratings of intelligence and IQ are rather small (.20-.25) in college samples. Possible improvements in traditional methods were investigated by employing (a) indirect questions and (b) aggregation. To evaluate these improvements, we compared the validity of aggregated and unaggregated versions of direct measures with four indirect measures: Gough's Intellectual efficiency scale, Hogan's Intellect composite scale, Sternberg's Behavior Check List, and Trapnell's Smart scale. We also compared the performance of a novel self-report measure, Paulhus' Over-Claiming Questionnaire, which shares properties of IQ tests and self-report measures. All measures were administered to two large samples of undergraduates (Ns = 310, 326), who also took an IQ test. Results with traditional self - reports showed that both direct and indirect measures can reliably predict IQ scores but the validity cap appears to be .30 in our competitive college sample. As a rule, the most valid of the traditional items were global characterizations of mental ability; Aggregation benefited indirect more than direct measures. The novel measure, the Over-Claiming Questionnaire, outperformed all other measures with a validity cap of about .50.Arts, Faculty ofPsychology, Department ofGraduat