THE UTILITY OF THE CONFLUENCE MODEL - DO VARIABLES OF FAMILY-STRUCTURE EXPLAIN COGNITIVE ACHIEVEMENT

The consequences of variables of family structure, especially family s ize and birth order, upon cognitive achievement are focused. First the confluence model of Zajonc and colleagues will be presented and discu ssed. Then an empirical study will be performed which tries to relate variables of family structure to language and intelligence scores of p reschool children. The study using analysis of variance is based on re sults of two language and one intelligence tests of 185 children (at t he age of four and a half years) complemented by an index of socio-eco nomic status. Regarding family size only a few significant differences result. In those cases an achievement decline of children with two an d more siblings is existing. The findings show that socio-economic sta tus should be controlled because the effect of family size upon cognit ive achievement differs in the various status groups. Regarding birth order there exist almost no differences. The objections to the validit y of the confluence model expressed in many follow-up studies are supp orted by our analysis. Furthermore the mathematical formalization of p arts of the model seems to be problematic and needless.