The impetus for our study was the contention of both Lynn [Lynn, R. (1991) "Race differences in intelligence: A global perspective." "Mankind Quarterly," 31, 255-296] and Rushton [Rushton, J. P. (1995). "Race, evolution and behavior: A life history perspective." New Brunswick, NJ: "Transaction"; Rushton, J.…

The hypothesis that racial differences in IQ stem from differences in components of executive systems including knowledge base, control processes, and metacognition was investigated. Group differences in metamemory, strategy use, and general knowledge, but not perceptual efficiency, were observed. Metamemory predicted crystallized but not fluid…

IQ tests and intelligence were discussed from an evolutionary perspective and implications concerning legal decisions and social policy were presented. It was concluded that disproportionate social and economic benefits need not result from the use of IQ tests in the selection of educational and occupational elites. (RD)

R. Herrnstein and C. Murray, in "The Bell Curve," stated six propositions concerning a "g" factor of intelligence. These propositions are found to be reasonably well supported in the scientific literature. These conclusions can be reached whether or not one accepts Herrnstein and Murray's claims about the social significance of…

Borkowski and Krause (1983) concluded that the locus of black-white intelligence differences lies in metaprocesses not elementary cognitive processes. However, some variables were difference scores with unacceptably low reliability. Magnitude comparisons of racial differences give a different picture of results; comparable differences in measures…

Asian-American, White, and Black Children in grades 2-6 were tested for intelligence, achievement, and short-term memory. Factor analysis yielded two main factors: memory and general intelligence. The three groups differed distinctly at every grade level. Achievement correlated more with memory than with general intelligence. (Author/CP)

Jensen (1985) caused us to reexamine earlier findings. After correcting perceptual efficiency and executive systems measures for unreliability, original conclusions remain tenable. Control processes are factors in understanding race-related differences in intelligence. We do not deny the association of "speediness" but argue for a multidimensional…

Genetic influence was estimated on Wechsler Intelligence Scale for Children subtests from inbreeding depression scores calculated on cousin marriages in Japan (n=1,854 children) and correlated with American Black-White racial differences. The genetic contribution of racial differences in cognitive performance may be more robust than was previously…

The author refutes Humphrey's test of the Spearman hypothesis. A fair test requires that Black and White samples not be selected on any g-correlated variable, including socioeconomic status. Humphrey's factor analysis on test-score means of demographic groups, rather than on individuals, inflates g loadings and biases results. (LMO)

This study examines cultural bias in the Wechsler Intelligence Scale for Children. Results indicated no evidence of specific factors peculiar to Blacks v Whites, and rank order of item difficulties was similar in both groups. Race differences were due to differences in mental maturity rather than to test bias. (Author/RD)

Swedish longitudinal studies of twins support Scarr-Salapatek's explanation of nature-nurture influences on intelligence. This model predicts more genetic variance in test results for advantaged than disadvantaged groups. Jensen's work, however, suggests equal amounts of variance among different social classes. (Author/CP)

Relationship between ability tests and race and issues of famous lawsuits concerning possible bias in intelligence tests are summarized. Reasons for the origins of ethnic and racial differences in general intellectual ability are considered. Prospects for the reduction of group differences and conflicts are discussed. (SLD)

This author reviews published data and presents new data relevant to the Spearman hypothesis concerning racial differences on cognitive tests. He concludes that across-the-board difference between SES groups occurs primarily on the general factor, and that there are major determinants of race differences independent of the general factor.…

The author responds to criticisms made by Jensen pertaining to tests of the Spearman hypothesis. The near-zero correlation between Blacks and low socio-economic status Whites is neither an artifact of methodology nor a sampling fluke. Low and high SES White differences are highly correlated with general factor loadings. (LMO)