Responds to "Birth Order and Intelligence: Further Tests of the Confluence Model" by Robert D. Retherford and William H. Sewell. Reviews their arguments and suggests that their analyses of the Wisconsin Longitudinal Study data support rather than contradict the model. (CJS)

Statistical models for school effectiveness rankings are assessed. An analysis of linear models with fixed regression parameters and models with separate regression parameters for each school is presented. In the first case, the regression lines are parallel and the ranking of the schools is the same for all student backgrounds. In the second…

Confluence theory was developed to explain the negative effects of birth order on intelligence. Using aggregate, between-family, within-family, and paired-sibling data from the Wisconsin Longitudinal Study, tests the mathematical form of confluence theory and finds no support for it. Suggests that statistical methods used to fit the model to the…