Theoretical predictions, based on the confluence model, were made for data from six national surveys of intellectual performance, each relating intellectual performance scores to family configuration variables. The confluence model was capable of accurate prediction in all cases when three parameters were estimated. (Author/RD)

Patterns of intellectual ability of Arab children aged 6 to 16 years were examined using the new Arab WISC-R. As in prior work, a distinct profile emerged: relative superiority in Verbal over Performance IQ's which diminished with age as a flat profile emerged in adolescence. An environmental explanation is offered. (Author/RD)