In this post, I will review studies comparing the predictive validity of cognitive ability and parental socioeconomic status (SES) on academic achievement. Parental SES is usually measured via some combination of parental income, educational attainment, and occupational status. Academic achievement is measured either through grades or achievement test scores. A clear picture emerges from each study cited in this post: cognitive ability is a far superior predictor of academic achievement than is parental SES.
Most people are aware that there are significant disparities between blacks and whites in the United States with regard to a wide range of important social outcomes, including crime, income, education, poverty, welfare usage, etc. For almost every measurable metric of important life outcomes, blacks perform significantly worse than whites. In this post, I will cite studies showing that many of these disparities are likely caused by the significant cognitive differences between blacks and whites. I begin by illustrating a few examples of the disparities between blacks and whites with respect to important life outcomes. Then I briefly review evidence demonstrating the predictive validity and causal influence of cognitive ability for these outcomes. Next, I present data illustrating the scope and magnitude of the black-white cognitive ability gap. Finally, I provide evidence indicating that many of the aforementioned disparities between blacks and whites are (mostly) eliminated after controlling for youth cognitive ability.
In a previous post, I provided reasons to be skeptical of SES-based explanations of black criminality. This post provides studies that attempt to more rigorously examine the relationship between SES and black criminality. At the city and state level, crime is more strongly associated with the presence of blacks than it is with low-SES conditions. At the neighborhood level, studies suggest that controlling for SES can statistically account for a moderate portion of the black-white gaps in crime (although findings are mixed on the magnitude of the explained gap). Regardless, as I will argue below, such studies cannot demonstrate causality. That is, they cannot demonstrate that racial differences in neighborhood SES cause any portion of the racial gap in crime.