In this paper, social mobility is measured by looking at the extent to which family background determines socioeconomic success. Roughly speaking, social mobility can be measure by means of two distinct types of correlations: intergenerational correlations and sibling correlations.

The model presented in the paper generates important implications concerning how the allocation of resources between children varies across income groups. In the model, poor and middle-income families tend to channel their resources into a few children whereas rich families (and perhaps very...