This article analyzes concerns about market power and inequality in a model with multiple sectors, heterogeneous abilities, endogenous labor supply, and nonlinear income taxation. Proportional markups with no profit dissipation have no effect on the economy, and a policy that reduces a nonproportional markup raises (lowers) welfare when it is higher (lower) than a weighted average of other markups. With proportional (partial or full) profit dissipation, proportional markups are equivalent to a downward shift of the distribution of abilities, and the optimal policy rule with nonproportional markups maximizes consumer plus producer surplus despite concerns for distribution and labor supply distortion.
"Market Power and Income Taxation."
American Economic Journal: Economic Policy,
Market Structure, Pricing, and Design: Oligopoly and Other Forms of Market Imperfection
Allocative Efficiency; Cost-Benefit Analysis
Taxation and Subsidies: Efficiency; Optimal Taxation
Taxation and Subsidies: Externalities; Redistributive Effects; Environmental Taxes and Subsidies
Personal Income and Other Nonbusiness Taxes and Subsidies; includes inheritance and gift taxes
Oligopoly and Other Imperfect Markets