The purpose of this post is to provide a comprehensive overview of racial and ethnic disparities on cognitive and academic tests in the United States. The primary focus is on black and white Americans because most data focuses on comparing these groups, but I’ll also mention disparities for other groups (mainly Hispanics and Asians) when such data is available. I start by reviewing data on the magnitude of racial disparities in cognitive ability. Next, I consider racial disparities in other kinds of tests, including college admissions and academic achievement tests, finding that these disparities are about as large as disparities in cognitive ability. Then, to better contextualize the magnitude of racial disparities in test scores, I compare racial gaps to gaps between other groups, such as students from different countries or different levels of socioeconomic status. Finally, I present data on the ubiquity of test score gaps, showing that the gaps persist through all levels of education, across all geographical units of analysis, and across all socioeconomic levels.
In a previous post, I cited several studies showing that racial disparities in many important social outcomes are largely driven by racial disparities in cognitive ability. This post will expand on those findings by demonstrating similar patterns in 3 nationally representative datasets that I have not yet considered elsewhere. The datasets include data on socioeconomic outcomes from the early 1990s to early 2010s. I will examine how racial disparities in educational attainment, occupational prestige, and income (the three primary measures of socioeconomic status, as explained here) are related to various factors such as parental income, high school academic achievement, and family structure. My main focus is on disparities between blacks and whites, where I find that the vast majority (over 90%) of the adulthood income gap is explained by some combination of the aforementioned factors, and virtually all of the disparity in educational attainment and occupational prestige are explained by high school achievement.
In previous posts, I have emphasized the predictive power of IQ on a variety of outcomes such as education academic achievement, educational attainment, occupational prestige, income, and crime. I referenced studies showing that IQ is a better predictor of many of these outcomes compared to other metrics traditionally assumed to predict success. For example, many studies show that IQ predicts education, occupation, and income better than many metrics that people assume to be predictors of success – e.g. parental SES, parental income, parental education, etc. Such data might lead some to believe that IQ is by far the single best predictor of conventional measures of success within Western societies. I wish to challenge that idea in this post. I do not necessarily deny that IQ is generally the best predictor of certain measures of success. Rather, I insist that there are a variety of personality traits that are better predictors for certain measures of success. There are many personality traits that I could use to support my argument, such as conscientiousness or locus of control. In this post, I will focus on self-regulation. I will present data showing that self-regulation predicts a variety of important outcomes independent of various confounders (including IQ and parental SES).
In this post, I will show specific examples of group differences in success that are not the result of differences in intelligence or cognitive ability. I will begin by citing evidence Asian American overachievement in a variety of metrics of success – e.g., academic achievement, income, occupational prestige, etc. – are not entirely the result of an advantage in cognitive ability. In the future, I plan to add data to this post showing that other groups – including Jews, women, and certain groups of black people – also achieve more than what would be predicted based on their intelligence.