Gary-Bobo, Robert J.; Trannoy, Alain - 2013
and an elementary optimal income-tax problem à la Mirrlees. This combination can be called a graduate tax. There are two … income tax depending only on earnings, and a loan repayment, depending only on education. Therefore, optimal loan repayments … of moral hazard; it typically involves cross-subsidies; generically, it cannot be decomposed as the sum of an optimal …