The assumption that a singular biological resource pool embedded in the central nervous system results in differences in macrolevel outcomes because of the constraints it imposes on efficiencies of microlevel processing is refuted. Moderating effects on the causal pathways between microlevel and macrolevel performance are discussed. (SLD)

Few books have generated as much controversy as the recently published "The Bell Curve: Intelligence and Class Structure in American Life." The tremendous polarization on the issue of the relationship between intelligence quotient (IQ) to race and social class, reinforced by the book, and the potential this book has for undermining…

A model-fitting analysis of the covariance structure of an intelligence quotient (IQ) data set is reported using a model that considers additive and nonadditive genetic parameters and shared and nonshared environment parameters that permit different estimates for different types of relatives. The use of LISREL for such purposes is reviewed. (SLD)