The Science and Politics of I.Q.

adopted children adoptive families adoptive homes assert assessments assortative mating average Binet biological mothers birth weight Brigham Burt and Howard Burt's C₁ calculated child child's I. Q. dominance DZ pairs EKJ figure environmental estimate Eugenics Eugenics Research Association evidence fact female DZs foster homes genes genetically determined genotypes grams Harry Laughlin heavier twin hereditarian heredity heritability I.Q. correlation I.Q. scores I.Q. tests identical twins immigration indicated individuals intraclass correlation Juel-Nielsen kinship correlations Leahy male DZs mean I.Q. measure median mental testing MZ and DZ observed paper polygenes population predict procedure Professor Herrnstein Professor Jensen pseudopairing Psychology R. J. Herrnstein range raw scores resemblance sample Scarr selective placement separated twins Shields sib correlation siblings Skodak and Skeels social class standard deviation Stanford-Binet statistically significant Terman test scores tion twin pairs twin studies twins reared Vandenberg variance within-pair Yerkes zygosity