Sibling variable correlates of children's academic achievement: family-group differences

The study examined the proposition that relationships among sibling variables, intellectual ability, and academic achievement vary for children from different family-environment groups. Data were collected from 900 11-yr.-old Australian children and their parents. In the analysis, the children were classified into four family contexts that were defined conjointly by family social status and parents' academic socialization. Within each family group, regression surfaces were constructed from models that included terms to account for possible linear, interaction, and curvilinear associations among the variables. The results suggested the general proposition that within the family-environment groups, sibling variables were not related to academic achievement at different levels of children's ability. However, the findings indicated that there were variations to this general proposition. Indeed, there were a number of complex associations between the sibling variables and children's academic achievement in the different family-environment groups.