There is overwhelming evidence showing the predictive validity of cognitive ability for important life outcomes. Cognitive ability measured as early as age 6 has a strong association with one’s future success in a number of important outcomes, including academic achievement, occupational performance, income, educational attainment, occupational prestige, criminality, self-control, and health. The associations are typically large, often making cognitive ability the best predictor for such outcomes. In this post, I will cite research showing this evidence. I will begin with some background on cognitive ability, including definitions, the distributions of IQ test scores, the stability of cognitive ability test scores, and expert consensus on the validity of cognitive ability. Finally, I will cite data demonstrating the predictive validity of cognitive ability in academic achievement, occupational performance, socioeconomic success, anti-social behavior, and health.
Achievement beyond IQ: childhood self-regulation
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).
The black-white cognitive ability gap and social outcomes
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.
The magnitude and scope of black crime
The purpose of this post is to cite the extent of black crime around the world. The first section is concerned with black crime in the United States. This section should not be terribly surprising to most people since I assume (hope) most people are aware that black people are disproportionately engaged in crime in the United States. I believe the latter two sections contain information that most people are not aware of. The second section covers misconduct among black children in the United States. The third and final section covers black crime and misconduct outside of the United States. The last two sections, especially the last section, will probably be educational for the vast majority of people reading this post. If not, the post at the very least serves as a useful fact sheet for those interested in this topic.
The early emergence of black-white disparities
Most people are aware of the significant disparities between blacks and whites regarding a wide range of important social outcomes, including crime, income, education, poverty, welfare usage, etc. I have written extensively on racial disparities in crime and on the degree to which disparities in IQ explain many of the important racial disparities. In this post, I will review studies and data that show that many of these disparities appear extremely early. Specifically, I will show that disparities in IQ, cognitive skills, misconduct, and self-regulation appear extremely early in life. For each of these categories, I will show that we find black-white disparities at pre-school age or even earlier. The general pattern for these disparities is that they gradually grow as children age, until the magnitude of the disparities eventually mirror the gaps that we find between black and white adults.
Police killings and black crime
In light of the killing of George Floyd, there has been much discussion regarding anti-black bias in the criminal justice system (CJS) in the United States. It seems to me that the mainstream assumption is that the disproportionate police killings of black people is strong evidence of an anti-black bias in the CJS. My goal in this post is to refute this assumption. I believe that an honest and impartial assessment of all of the relevant data provides strong reason to deny that the disproportionate police killings of blacks is evidence of anti-black bias. I will argue that the best explanation of disproportionate police killings against blacks doesn’t involve any appeal to an anti-black bias. The best explanation consists in the fact that black people disproportionately engage in criminal activity and the fact that the police disproportionately kill criminals.
Exploring two common explanations of the black-white crime gap
The purpose of this post is to explore two commonly hypothesized explanations of the high levels of criminality in the black population. The first explanation states that high rates of black crime is primarily the result of systemic racism against blacks. The second explanation states that high rates of black crime is primarily the result of the structural or socioeconomic circumstances that black people find themselves in. I will present data that should prompt skepticism of both of these explanations. I’ll begin by describing racial differences in crime.
Studies attempting to explain the black-white crime gap
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.
Causes of disproportionate black crime
In a previous post, I argued that systemic racism and socioeconomic status (SES) were poor explanations of disproportionate levels of black crime. I concluded with the claim that the intelligence gap (or IQ gap), not the SES gap, is the primary cause of the disproportionate levels of black crime. In other words, the IQ gap is the primary cause of the disparities in crime between blacks and whites. I will defend this claim in the first half of this post. Another significant cause of the black-white crime gap seems to be differences in family structure between blacks and whites, e.g. racial differences in the rates of single-mother households and out-of-wedlock birth rates. I will explore the importance of family structure in the second half of the post.