We analyze the optimal nonlinear income tax schedule for taxpayers with multiple incomes and multiple unobserved characteristics. We identify smoothness assumptions and extensions of the single crossing conditions that enable the characterization of the optimum through variational calculus. Both...

We analyze the optimal nonlinear income tax schedule when taxpayers earn multiple in- comes and differ along many unobserved dimensions. We derive the necessary conditions for the government's optimum using both a tax perturbation and a mechanism design approach, and show that both methods...

We analyze the optimal nonlinear income tax schedule when taxpayers earn multiple incomes and differ along many unobserved dimensions. We derive the necessary conditions for the government's optimum using both a tax perturbation and a mechanism design approach, and show that both methods produce...

This paper studies the design of tax systems that implement a planner's second-best allocation in a market economy. An example shows that the widely used Mirrleesian (1976) tax system cannot implement all incentive-compatible allocations. Hammond's (1979) "principle of taxation" proves that any...

I characterize the optimal linear commodity taxes when households differ in multiple characteristics, in presence of an optimal non-linear tax schedule on the households' labour incomes. The optimal distortions caused by a linear commodity tax are larger if, conditional on labour income, more...

I characterize the optimal linear commodity taxes when households differ in multiple characteristics and earn multiple incomes, in presence of an optimal non-linear tax schedule on the households' labour incomes. The government should tax a commodity more heavily if, conditional on labour...

This paper documents the integration of microsimulation tools for direct taxation, indirect taxation, and social benefits in the context of the European tax and benefit simulator, EUROMOD. Integration has been developed parallely for the two countries, Belgium and Germany. The paper at hand...

This paper documents the integration of microsimulation tools for direct taxation, indirect taxation, and social benefits in the context of the European tax and benefit simulator, EUROMOD. Integration has been developed in parallel for two countries: Belgium and Germany. The paper at hand...

There is increasing empirical evidence that people systematically differ in their rates of return on capital. We derive optimal non-linear taxes on labor and capital income in the presence of such return heterogeneity. We allow for two distinct reasons why returns are heterogeneous: because...

There is increasing empirical evidence that people systematically differ in their rates of return on capital. We derive optimal non-linear taxes on labor and capital income in the presence of such return heterogeneity. We allow for two distinct reasons why returns are heterogeneous: because...