The IQ Meritocracy Reconsidered: Cognitive Skill and Adult Success in the United States

Working with data drawn from the Project Talent and Kalamazoo Brothers samples, we test six propositions for which empirical support should be found if an IQ meritocracy governs the process of socioeconomic achievement. We find that the model of an IQ meritocracy is only partially supported. There is a trend toward decreasing direct effects of father's occupational status and family size on educational attainment and occupational status. No such trend is evident for the effects of father's education. Measured ability has an increasing effect on the attainment of a college education and on occupational status but a declining effect on the completion of high school. Cognitive ability is a significant channel for mobility from socioeconomic origins, but it does little to reduce the influences of family membership within socioeconomic groups. Both socioeconomic and other unmeasured familial factors, unrelated to cognitive ability, are important determinants of educational attainment and early occupational status. A significant fraction of the apparent relationship of cognitive ability to educational attainment is spurious, and the vast preponderance of inequality in schooling and adult economic success is unrelated to differences in measured ability. The effect of ability differences on earnings is, nevertheless, large and robust. Finally, we conclude our analysis by questioning the identification of cognitive ability with merit.