A model is provided whereby a monopolist firm chooses to price its product at zero. This outcome is shown to be driven by the assumption of ‘free disposal' alongside selection markets (where prices impact on a firm's costs). Free disposal creates a mass point of consumers whose utility from...

A controversial feature of Medicare Part D is its reliance on private insurers to negotiate drug prices and rebates with retail pharmacies and drug manufacturers. Central to this controversy is whether increases in market power--an undesirable feature in most settings--confer benefits in health...

This paper develops and estimates a search and bargaining model designed to measure the welfare loss associated with frictions in oligopoly markets with negotiated prices. We use the model to quantify the consumer surplus loss induced by the presence of search frictions in the Canadian mortgage...

The recent fall of labor's share of GDP in numerous countries is well-documented, but its causes are poorly understood. We sketch a “superstar firm” model where industries are increasingly characterized by “winner take most” competition, leading a small number of highly profitable (and...

This paper investigates whether an emissions tax (equivalent to an emissions cap) maximizes social welfare (defined as the sum of consumer and producer surplus) in the presence of incomplete regulation (leakage) or market power by analyzing an intensity standard regulating emissions per unit of...

In this paper we develop a monopolistic competition model where firms exercise their market power across multiple products. Even with CES preferences, markups are endogenous. Firms choose their optimal product scope by balancing the net profits from a new variety against the costs of...

The fall of labor's share of GDP in the United States and many other countries in recent decades is well documented but its causes remain uncertain. Existing empirical assessments of trends in labor's share typically have relied on industry or macro data, obscuring heterogeneity among firms. In...

We develop a tractable quantitative, general equilibrium, oligopsony model of the labor market that we use to measure the macroeconomic implications of labor market power. Strategic interaction complicates inference of parameters that are key to this exercise. To address this challenge, we...

Does significant market power or the presence of large rents affect optimal income taxation, calling for greater redistribution due to tainted gains? Or perhaps less because of an additional wedge that distorts labor effort? Do concerns about inequality have implications for antitrust,...