Validity of race and IQ Intelligence, IQ, g and IQ tests Main articles: Intelligence quotient and Intelligence

The concept of intelligence and the degree to which intelligence is measurable is a matter of debate. While there is some consensus about how to define intelligence, it is not universally accepted that it is something that can be unequivocally measured by a single figure.[32] A recurring criticism is that different societies value and promote different kinds of skills and that the concept of intelligence is therefore culturally variable and cannot be measured by the same criteria in different societies.[32] Consequently, some critics argue that proposed relationships to other variables are necessarily tentative.[33]

In relation to the study of racial differences in IQ test scores it becomes a crucial question what exactly it is that IQ tests measure. Arthur Jensen was a proponent of the view that there is a correlation between scores on all the known types of IQ tests and that this correlation points to an underlying factor of general intelligence, or g. In most conceptions of g it is considered to be fairly fixed in a given individual and unresponsive to training or other environmental influences. In this view test score differences, especially in those tasks considered to be particularly "g-loaded" reflect the test takers innate capability. Other psychometricians argue that, while there may or may not be a general intelligence factor, performance on tests rely crucially on knowledge acquired through prior exposure to the types of tasks that such tests contain. This view would mean that tests cannot be expected to reflect only the innate abilities of a given individual, because the expression of potential will always be mediated by experience and cognitive habits. It also means that comparison of test scores from persons with widely different life experiences and cognitive habits is not an expression of their relative innate potentials.[34] Race Main articles: Race (classification of humans) and Race and genetics

The majority of anthropologists today consider race to be a sociopolitical phenomenon rather than a biological one,[35] a view supported by considerable genetics research.[36][37] The current mainstream view in the social sciences and biology is that race is a social construction based on folk ideologies that construct groups based on social disparities and superficial physical characteristics.[38] Sternberg, Grigorenko & Kidd (2005) state, "Race is a socially constructed concept, not a biological one. It derives from people's desire to classify."[33] The concept of human "races" as natural and separate divisions within the human species has also been rejected by the American Anthropological Association. The official position of the AAA, adopted in 1998, finds that advances in scientific knowledge have made it "clear that human populations are not unambiguous, clearly demarcated, biologically distinct groups" and that "any attempt to establish lines of division among biological populations [is] both arbitrary and subjective."[39] However within population genetics there is ongoing debate about whether the social category of "race" can and should be used as a proxy for individual genetic ancestry. With current methods of genetic analysis it is possible to determine the composition of genetic ancestry of an individual with significant precision. This is because different genes occur with different frequencies in different geographically defined populations, and by correlating a large amount of genes through cluster analysis it is probable to determine with high likelihood the geographic origins of an individual through DNA. This suggests to some that the classical socially defined genetic categories really have a biological basis, in the sense that racial categorization is a visual estimate of a person's continental ancestry based on their phenotype—which correlates with genotypical ancestry as determined by DNA tests.

Race in studies of human intelligence is almost always determined using self-reports, rather than based on analyses of the genetic characteristics of the tested individuals. According to psychologist David Rowe, self-report is the preferred method for racial classification in studies of racial differences because classification based on genetic markers alone ignore the "cultural, behavioral, sociological, psychological, and epidemiological variables" that distinguish racial groups.[40] Hunt and Carlson write that "Nevertheless, self-identification is a surprisingly reliable guide to genetic composition. Tang et al. (2005) applied mathematical clustering techniques to sort genomic markers for over 3,600 people in the United States and Taiwan into four groups. There was almost perfect agreement between cluster assignment and individuals' self-reports of racial/ethnic identification as white, black, East Asian, or Latino."[41] Sternberg and Grigorenko disagree with Hunt and Carlson's interpretation of Tang, "Tang et al.'s point was that ancient geographic ancestry rather than current residence is associated with self-identification and not that such self-identification provides evidence for the existence of biological race."[42]

Anthropologist C. Loring Brace[43] and geneticist Joseph Graves disagree with the idea that cluster analysis and the correlation between self-reported race and genetic ancestry support biological race.[44] They argue that while it is possible to find biological and genetic variation corresponding roughly to the groupings normally defined as races, this is true for almost all geographically distinct populations. The cluster structure of the genetic data is dependent on the initial hypotheses of the researcher and the populations sampled. When one samples continental groups, the clusters become continental; if one had chosen other sampling patterns, the clusters would be different. Kaplan 2011 therefore concludes that, while differences in particular allele frequencies can be used to identify populations that loosely correspond to the racial categories common in Western social discourse, the differences are of no more biological significance than the differences found between any human populations (e.g., the Spanish and Portuguese).

Earl B. Hunt agrees that racial categories are defined by social conventions, though he points out that they also correlate with clusters of both genetic traits and cultural traits. Hunt explains that, due to this, racial IQ differences are caused by these variables that correlate with race, and race itself is rarely a causal variable. Researchers who study racial disparities in test scores are studying the relationship between the scores and the many race-related factors which could potentially affect performance. These factors include health, wealth, biological differences, and education.[45] Group differences Globe icon. The examples and perspective in this article deal primarily with the United States and do not represent a worldwide view of the subject. You may improve this article, discuss the issue on the talk page, or create a new article, as appropriate. (February 2013) (Learn how and when to remove this template message)

The study of human intelligence is one of the most controversial topics in psychology. It remains unclear whether group differences in intelligence test scores are caused by heritable factors or by "other correlated demographic variables such as socioeconomic status, education level, and motivation."[46] Hunt and Carlson outlined four contemporary positions on differences in IQ based on race or ethnicity. The first is that these reflect real differences in average group intelligence, which is caused by a combination of environmental factors and heritable differences in brain function. A second position is that differences in average cognitive ability between races are caused entirely by social and/or environmental factors. A third position holds that differences in average cognitive ability between races do not exist, and that the differences in average test scores are the result of inappropriate use of the tests themselves. Finally, a fourth position is that either or both of the concepts of race and general intelligence are poorly constructed and therefore any comparisons between races are meaningless.[41] United States test scores A number of studies have reached the conclusion that IQ tests may be biased against certain groups.[71][72][73][74]