This paper highlights the possibility that negative marginal tax rates arise in an intensive-margin optimal income tax model where wages are exogenous and preferences are homogeneous, but where agents differ both in skills (labor market productivity) and their needs for a work-related...

A standard result in the optimal taxation literature is that, when agents differ in market ability and the government aims at redistributing from high- to low-skilled agents by means of an optimal nonlinear labor income tax and a set of commodity taxes, an optimally designed commodity tax...