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...

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...

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...

We study the optimal taxation of risk-free and excess capital income with heterogeneous rates of return, alongside an optimal nonlinear earnings tax. Households can hold three assets: one risk-free, one risky but diversifiable, and one a private investment with idiosyncratic risk whose expected...