We study incumbency advantage in a dynamic game with incomplete information between an incumbent and a voter. The incumbent knows the true state of the world, e.g., the severity of an economic recession or the level of criminal activities, and can choose the quality of his policy. This quality and the state of the world determine the policy outcome, i.e., the economic growth rate or the number of crimes committed. The voter only observes the policy outcome and then decides whether to reelect the incumbent or not. Her preferences are such that she would reelect the incumbent under full information if and only if the state of the world is above a given threshold level. In equilibrium, the incumbent is reelected in more states of the world than he would be under full information. In particular, he chooses inefficient policies and generates mediocre policy outcomes whenever the voter's induced belief distribution will be such that her expected utility of reelecting the incumbent exceeds her expected utility of electing the opposition candidate. Hence, there is an incumbency advantage through inefficient policies. We provide empirical evidence consistent with the prediction that reelection concerns may induce incumbents to generate mediocre outcomes.JEL code: D72, C73

We study location games where market entry is costly and occurs sequentially, and where consumers are nonuniformly distributed over the unit interval. We show that for certain classes of densities, including monotone and-under some additional restrictions-hump-shaped and U-shaped ones, equilibrium locations can be determined independently of when they are occupied. Our analysis reveals a number of peculiarities of the uniform distribution. Extensions of the model allow for price competition and advertisement in media markets, winner-take-all competition, trade-offs between profits in the short and the long run, and firms operating multiple outlets. We are grateful to two anonymous referees and the coeditor for their comments and suggestions. The article has also benefited from comments

Mechanisms according to which private intermediaries or governments charge transaction fees or indirect taxes are prevalent in practice. We consider a setup with multiple buyers and sellers and two-sided independent private information about valuations. We show that any weighted average of revenue and social welfare can be maximized through appropriately chosen transaction fees and that in increasingly thin markets such optimal fees converge to linear fees. Moreover, fees decrease with competition (or the weight on welfare) and the elasticity of supply but decrease with the elasticity of demand. Our theoretical predictions fit empirical observations in several industries with intermediaries.

We analyze the competitive effects of mergers in markets with buyer power. Using mechanism design arguments, we show that without cost synergies, mergers harm buyers, regardless of buyer power. However, buyer power mitigates the harm to a buyer from a merger of symmetric suppliers. With buyer power, a merger increases incentives for entry, increases investment incentives for rivals, and can increase investment incentives for merging parties. Because buyer power reduces the profitability of a merger, it increases the profitability of perfect collusion relative to a merger. Cost synergies can eliminate merger harm, but also render otherwise profitable mergers unprofitable.

We discuss the economics literature relevant to the design of centralized two-sided market mechanisms for environments in which both buyers and sellers have private information. The existing literature and the history of spectrum auctions, including the incentive auction currently being designed by the FCC, can be employed to analyze such mechanisms. We compare the revenue– efficiency trade-off in an environment with private information on one side of the market versus the trade-off with private information on both sides of the market; we provide an impossibility theorem for the efficient allocation of goods using a deficit-free mechanism when there is private information on both sides of the market; we discuss practical deficit-free mechanisms for various environments with two-sided private information; and we provide a synthesis to guide market design efforts and related research going forward. (JEL D44, D47, D82, H82)