The importance of family background in different socioeconomic groups

It is well-documented that family background is important in virtually all aspects of life. While there is a vast literature on the heterogeneity of the importance of family background, often measured in terms of sibling correlations, across countries, less is known about heterogeneities across social groups within a country. In this project, using Swedish register data, we compare sibling differences in educational attainment, earnings and ability across fine-grained groups defined by parental socioeconomic status. There is a long-standing theoretical discussion on the relationship between sibling differences and parental socioeconomic status in which the predictions depend on if parents reinforce, or compensate for, initial ability differences between siblings. By adding to a limited empirical literature, this project can help clarify the relevance of the different theories and potentially answer the question of whether life is more formed by family background in certain groups than in others.