Income distribution, non-convexities and the fertility-income relationship

This paper presents a model of inequality, income determination and fertility, that is consistent with aggregated stylized facts and individual survey data on fertility and income. It shows that indivisibilities in human capital investments limit the possibility of trade-off between the quality and the quantity of children. This generates a non-monotonic relationship between income and fertility at the micro level. On the aggregate, the total fertility rate can increase or decrease with income, depending on the income distribution of the population and on the private cost of education.