Educators, as applied scientists, must work in partnership with investigative scientists who are researching brain functions in order to reach a better understanding of gifted students and students who are intelligent but do not learn. Improper understanding of brain functions can cause gross errors in educational placement. Until recently, the…

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)