An application of the analysis of covariance structures to the psychogenetical study of impulsiveness

A method based on Jöreskog's approach to the analysis of covariance structures is applied to the genotype‐environment analysis of the covariation of four aspects of impulsiveness in male and female monozygotic and dizygotic twins. The data are consistent with a simple model which assumes additive gene action, random mating and environmental effects within families. Further, it is shown that genotypic factor loadings can be regarded as constant multiples of corresponding environmental loadings. Trait‐specific sex interactions are detected which suggest that some mechanism of sex‐limitation could contribute to specific variation.