Suppliers of differentiated goods make simultaneous pricing decisions, which are strategically linked due to consumer preferences and the structure of production. Because of market power, the equilibrium is inefficient. We study how a policymaker should target a budget-balanced tax-and-subsidy...

In a wide variety of social settings (e.g. crime, education, political activism, technology adoption), players' returns to their efforts depend on how much effort others exert. Modeling these situations as a network game with strategic complementarities, we show that a player's cycle centrality...