We completely characterize the set of second-best optimal "menus" of student-loan contracts in a simple economy with risky labour-market outcomes, adverse selection, moral hazard and risk aversion. The model combines structured student loans and an elementary optimal income-tax problem à la...

We assume that students can acquire a wage premium, thanks to studies, and form a rational expectation of their future earnings, which depends on personal ability. Students receive a private, noisy signal of their ability, and universities can condition admission decisions on the results of...

We study the treatment effect of grade retention, using a panel of French junior highschool students, taking unobserved heterogeneity and the endogeneity of grade repetitions into account. We specify a multi-stage model of human-capital accumulation with a finite number of types representing...

In the present article, Tiebout meets Laffont and Tirole in the land of Fiscal Federalism. We use a non-trivial Principal-Multi-Agent model to characterize the optimal intergovernmental grant schedule, when the cost of local public goods depends on hidden characteristics and actions of local...

To evaluate pension reforms in public services, we put forward a simple criterion, the actuarial cost of a worker, per year of service. This measure of cost is the expected, discounted sum of net real wages and pension benefits, earned by a worker over his entire life cycle, divided by the...

We propose a model of discrimination in the market for mortgages. The model explains accepted loan applications and determines loan sizes and interest rates simultaneously. A competitive, and a discriminating monopoly version of the model are proposed. Offered interest rates and loan sizes are a...

In the home-care services industry, caregivers drive to visit patients scattered in a district and deliver various care services at the patient's home. We use a unique data set, with a standard panel structure, recording the hours of service and the exact number of miles traveled by each...

We examine how allowing individuals to emigrate to pay lower taxes abroad changes the optimal non-linear income tax scheme in a Mirrleesian economy. An individual emigrates if his domestic utility is less than his utility abroad net of migration costs, utilities and costs both depending on...

We investigate how the optimal nonlinear income tax schedule is modified when taxpayers can evade taxation by emigrating. We consider two symmetric countries with Maximin governments. Workers choose their labor supply along the intensive margin. The skill distribution is continuous, and, for...

We solve the non-linear income tax program for a rank-dependent social welfare function à la Yaari, expressing the trade-off between size and inequality using the Gini or related families of positional indices. The key idea is that when agents optimize and absent bunching, ranks in the actual...