Human capital formation with endogenous credit constraints

We study the accumulation of human capital and the behavior of consumption and earnings in a life cycle equilibrium model with endogenous borrowing constraints. Constraints arise endogenously from the inalienability of human capital and the limited punishments that creditors are able to impose on those who default. The endogeneity of borrowing constraints produces a number of interesting relationships. First, efficient borrowing limits are functions of individual observable characteristics and choices, especially ability and human capital investments. The connection between human capital investments and borrowing limits creates additional incentives to invest beyond those present in models with exogenous constraints. Second, government policies affect the incentives to default and, hence, the limits on private borrowing. As opposed to exogenous constraint models, additional subsidies for investment in human capital should be accompanied by increases in credit, since borrowers are more able to re-pay higher debts. Finally, general equilibrium considerations have an additional role, since borrowing limits depend on the returns to physical and human capital. We calibrate the model to