Environmental relations to cognitive abilities across three ethnic groups

Abstract

Using data on 1745 offspring from families In Hawaii and Korea, dimensions factored from environmental variables (broad definition, Including genetic Influences) are examined and related to cognitive abilities by means of multiple regression. Three ethnic groups were represented: Americans of European Ancestry (AEA'S, N=1122); Americans of Japanese Ancestry (AJA's, N=380); and native Koreans (N=243). Cognitive abilities are defined by factoring 15 tests into four factors: verbal, spatial, perceptual speed, and memory (DeFries, 1974). Also included was the first principal component (Spearman's 'g') from a previous analysis. Common factor analysis was used to factor environmental measures from each ethnic group Into 16 oblique dimensions. Coefficients of congruence show high similarities across groups for approximately three-quarters of the factors. Factors unique to each group are discussed. Second order structures show socio-economic status, parental and self ratings, family size, and family age to be Important cross-cultural areas of influence. Multiple correlations showed the total environment to be related most strongly to Spearman's 'g' followed by verbal ability, perceptual speed, spatial ability, and memory. Cross-cultural factors important to verbal ability were school work, amount of reading, and socio-economic status. Spatial ability was related to the subject's perception of their mathematical ability, and perceptual speed related to developmental and pregnancy problems. Spearman's 'g' showed diverse relationships across groups, but again school work, reading, and socio-economic status showed influence. In order to conceptualize patterns of relationships between environmental variables and cognitive abilities, simple (Pearson) environment-ability correlations were rank ordered for each ethnic-ability combination. These 15 patterns of correlations were then compared by means of Spearman's rank correlation (rho). The rho's were higher for pairwise comparisons within an ethnic group across abilities than for comparisons of similar abilities across ethnic groups. Comparisons across abilities, notably verbal, Spearman's 'g', spatial, and perceptual speed showed significant (p<.01) correlations, but these were generally lower than within ethnic group comparisons. In summary, highly congruent factors related to cognitive abilities across cultural groups in similar ways.