In this paper, we tackle the dilemma of pruning versus proliferation in a vertically differentiated oligopoly under the assumption that some firms collude and control both the range of variants for sale and their corresponding prices, likewise a multiproduct firm. We analyse whether pruning...

The China - Raw Materials dispute recently arbitrated by the WTO opposed China as defendant to the US, the EU and Mexico as claimants on the somewhat unusual issue of export restrictions on natural resources. For the claimants, Chinese export restrictions on various raw materials, of which the...

This paper studies regulatory policy interventions aimed at protecting sticky consumers who are exposed to exploitation. We model heterogeneous consumer switching costs alongside asymmetric market shares. This setting encompasses many markets in which established firms are challenged by new...

Biodiversity provides essential services to human societies. Many of these services are provided as public goods, so that they will typically be underprovided both by market mechanisms (because of the impossibility of excluding non-payers from using the services) and by government-run systems...

This paper studies the design of sin taxes when firms exercise market power. We outline an optimal tax framework that highlights how market power impacts the efficiency and redistributive properties of sin taxation, and quantify these effects in an application to sugar-sweetened beverage...

The Lerner index is widely used to assess firms' market power. However, estimation and interpretation present several challenges, especially for banks, which tend to produce multiple outputs and operate with considerable inefficiency. We estimate Lerner indices for U.S. banks for 2001-18 using...

Wages for the vast majority of workers have stagnated since the 1980s while productivity has grown. We investigate two coexisting explanations based on rising market power: 1. Monopsony, where dominant firms exploit the limited mobility of their own workers to pay lower wages; and 2. Monopoly,...