In an economy with both inter- and intra-region inequality and inconsistency between the objectives of local and central governments, this paper studies optimal non-linear federal (central) income tax under non-linear regional income taxes. Starting with a benchmark model without labor mobility,...

In a model with a continuum of imperfectly substitutable laborers and endogenous skill premiums, this paper derives optimal tax formulas as functions of social welfare weights and a small set of estimable statistics. It first demonstrates that differential capital tax, based on capital's effect...

Should automation be regulated? This paper studies optimal tax of robot and regulation of automation. A job assignment model is embedded into a Mirrleesian tax problem. A task may either be assigned to the robot or one type of labors, which naturally determines the automation rate. The robot can...