Analyses of National Longitudinal Survey data indicate that cognitive skill level affects access to high-skill occupations and earnings. Lower cognitive skill levels for African Americans and U.S.-born Mexican Americans explain a substantial proportion of income differences between these groups and European Americans but not the gender gap in pay…

Using data from the same source as that employed in Herrnstein and Murray's book, "The Bell Curve," this study reexamined links between the test scores of mothers and children, paying close attention to what the scores measure and whether these measurements mean the same things for blacks and whites. The study replicated Herrnstein and…