Optimal student loans and graduate tax under moral hazard and adverse selection
研究了在劳动力市场风险、逆向选择和道德风险并存时，如何设计最优的学生贷款合同菜单，并与最优所得税结合，发现最优还款需与收入挂钩或征收毕业生税，且存在中期均等化性质。
We characterize the set of second‐best “menus” of student‐loan contracts in an economy with risky labor‐market outcomes, adverse selection, moral hazard, and risk aversion. We combine student loans with optimal income taxation. Second‐best optima provide incomplete insurance because of moral hazard. Optimal repayments must be income contingent, or the income tax must comprise a graduate tax. Individuals are ex ante unequal because of differing probabilities of success, and ex post unequal, because taxation trades off incentives and redistribution. In addition, second‐best optima exhibit an interim equalization property: the poststudy but prework expected utilities of newly graduated student types must be equal.