Asymmetric first-price menu auctions under intricate uncertainty

This paper studies asymmetric first-price menu auctions in the procurement environment where the buyer does not commit to a decision rule and asymmetric sellers have interdependent costs and statistically affiliated signals. Sellers compete in bidding a menu of contracts, where a contract specifies a vector of characteristics and a payment required from the buyer for delivering these characteristics. The buyer does not commit ex-ante to a decision rule but rather upon observing all the menus offered by sellers chooses the best contract. This paper establishes the existence of a continuum of separating monotone equilibria in this game bounded above by the jointly ex-post efficient outcome and below by the jointly interim efficient outcome. It shows that the jointly ex-post efficient equilibrium outcome is the only ex-post renegotiation-proof outcome and it is also ex-ante robust to all continuation equilibria.     

Merger negotiations and ex-post regret

We consider a setting in which two potential merger partners each possess private information pertaining both to the profitability of the merged entity and to stand-alone profits, and we investigate the extent to which this private information makes ex-post regret an unavoidable phenomenon in merger negotiations. To this end, we consider ex-post incentive compatible mechanisms, which use both players' reports to determine whether or not a merger will take place and what each player will earn in each case. When the outside option of at least one player is known, the efficient merger decision can be implemented by such a mechanism under plausible budget-balance requirements. When neither outside option is known, we show that the potential for regret-free implementation is much more limited, unless the budget balance condition is relaxed to permit money-burning in the case of false reports.     

Sorting versus screening: Search frictions and competing mechanisms

In a market where sellers compete by posting trading mechanisms, we allow for a general search technology and show that its features crucially affect the equilibrium mechanism. Price posting prevails when meetings are rival, i.e., when a meeting by one buyer reduces another buyer's meeting probability. Under price posting buyers reveal their type by sorting ex-ante. Only if the meeting technology is sufficiently non-rival, price posting is not an equilibrium. Multiple buyer types then visit the same sellers who screen ex-post through auctions.     

The role of optimal threats in auction design

This paper studies revenue-maximizing auctions when buyers' outside options depend on their private information and are endogenously chosen by the seller. We show that the revenue-maximizing assignment of the object can depend crucially on the outside options that the seller can choose as threats. Depending on the shape of outside options, sometimes an optimal mechanism allocates the object in an ex-post efficient way, and, other times, buyers obtain the object more often than is efficient.     

Production and Abatement Distortions under Noisy Green Taxes

A pollution regulator seeking to maximize social surplus can be viewed as facing two efficiency problems. One is that, given abatement technology investment decisions, it should attempt to ensure that firms which should produce do produce and firms which should not produce do not produce. This ex-post efficiency problem is not trivial when there is noise concerning the extent of environmental damage a firm does. We use a Bayesian information framework to show that the regulator may find it efficient to tax a firm that reads as a high (low) damage polluter at less (more) than the damage reading. Unfortunately when an abatement decision has to be made, this ex-post efficient tax system also dampens the incentive to abate. In the absence of wrong-firm concerns, a regulator can solve the abatement problem by an ex ante declaration that taxes will not be adjusted for signal noise. However, the regulator has a commitment problem as such taxes may not be ex-post efficient. The most appropriate policy may involve a combination of instruments.     

外部选择与关系专用性投资激励——基于GHM模型的研究

现实中的契约总是不完全的,当自然状态被参与人观察到之后,为了保证交易有效率,通常会对事前契约进行再谈判.首先,论文研究了事后再谈判时参与人的外部选择对事后合作租金的分配影响及事前关系专用性投资激励问题;其次,根据外部选择是否具有约束力,将外部选择区分为威胁点和现状点.研究结果显示:当外部选择为现状点时,不完全契约会导致事前关系专用性投资不足;而如果事后外部选择为威胁点时,投资方会作出有效率投资或投资过度     

Information acquisition and full surplus extraction

It is well known that when agents' types are correlated, the mechanism designer can extract the entire surplus. This creates an incentive for agents to acquire information about other agents' types. Robust lotteries (are payment schemes that) support full extraction and partially robust lotteries support efficient implementation in the presence of information acquisition opportunities. Necessary and sufficient conditions for existence of robust and partially robust lotteries are derived. If an agent's information signal spans other agents' types then robust lotteries do not exist. However, if all agents report their signal realizations then robust lotteries exist in an extended type space.     

Communication in bargaining over decision rights

This paper develops a model of bargaining over decision rights between an uninformed principal and an informed but self-interested agent. We introduce two different bargaining mechanisms: tacit and explicit bargaining. In tacit bargaining, an uninformed principal makes a take-it-or-leave-it price offer to the agent, who then decides whether to accept or reject the offer. In the equilibrium of the game, the principal inefficiently screens out some agent types so that the agent's private information cannot be fully utilized when the decision is made. In explicit bargaining in which parties can communicate explicitly via cheap talk before tacit bargaining, however, an equilibrium with no such inefficient screening exists even when the conflict of interest is arbitrarily large. We also follow a mechanism design approach, showing that under certain conditions, explicit bargaining is an optimal bargaining mechanism that maximizes the joint surplus of the parties.     

Willingness to pay for a Green Energy program: A comparison of ex-ante and ex-post hypothetical bias mitigation approaches

The most persistently troubling empirical result in the contingent valuation method literature is the tendency for hypothetical willingness to pay to overestimate real willingness to pay. Two approaches, ex-ante and ex-post, have been developed to mitigate or eliminate the overstatement of hypothetical willingness to pay. The ex-ante approach addresses hypothetical bias in the survey design stage while the ex-post approach addresses hypothetical bias with follow-up questions to the hypothetical willingness to pay question. We find that willingness to pay estimates are similar when either the ex-ante or ex-post approach are employed. Our results suggest that the approaches should be considered as complements and not substitutes. Employing both approaches to mitigate hypothetical bias we estimate that the annual benefits of the regional amenities associated with a Green Energy program in North Carolina are $186 million.     

Optimal delegation with multi-dimensional decisions

This paper investigates optimal mechanisms in a principal–agent framework with a two-dimensional decision space, quadratic payoffs and no monetary transfers. If the conflicts of interest between the principal and the agent are different on each dimension, then delegation is always strictly valuable. The principal can better extract information from the agent by using the spread between the two decisions as a costly screening device. Delegation sets no longer trade off pooling intervals and intervals of full discretion but instead take more complex shapes. We use advanced results from the calculus of variations to ensure existence of a solution and derive sufficient and necessary conditions for optimality. The optimal mechanism is continuous and deterministic. The agent?s informational rent, the average decision and its spread are strictly monotonic in the agent?s type. The comparison of the optimal mechanism with standard one-dimensional mechanisms shows how cooperation between different principals controlling various dimensions of the agent?s activities facilitates information revelation.     

Welfare analysis of a market with pairwise meetings and asymmetric information

Summary We study the welfare properties of a market with pairwise meetings and asymmetric information, establishing an equivalence between asymptotically expost individually rational and asymptotically (ex-ante, interim and ex-post) efficient equilibrium sequences.We thank Andreu Mas-Colell, Eric Maskin, and Thomas Sjöström for having raised the question which led to the writing of this paper. We are grateful to Nicholas Yannelis and two anonymous referees for helpful comments.     

An efficient solution to the informed principal problem

In this paper I study mechanism design by an informed principal. I show that generically this problem has an ex-post efficient solution. In the equilibrium mechanism, the informed principal appropriates all expected social surplus, with each type of her getting all expected social surplus conditional on that type. This outcome is supported as a perfect sequential equilibrium of the informed principal game when the joint probability distribution from which the agents’ types are drawn satisfies two conditions: the well-known condition of Cremer and McLean and Identifiability condition introduced by Kosenok and Severinov [Individually rational, budget-balanced mechanisms and allocation of surplus, J. Econ. Theory (2002), forthcoming]. Conversely, these conditions are necessary for an ex-post efficient outcome to be attainable in an equilibrium of the informed principal game. Under these conditions only our equilibrium outcome constitutes a neutral optimum, i.e. cannot be eliminated by any reasonable concept of blocking [R. Myerson, Mechanism design by an informed principal, Econometrica 51 (1983) 1767-1797]. Identifiability and Cremer-McLean conditions are generic when there are at least three agents, and none of them has more types than the number of type profiles of the other agents.     

Why stare decisis?

All Courts rule ex-post, after most economic decisions are sunk. This can generate a time-inconsistency problem. From an ex-ante perspective, Courts will have the ex-post temptation to be excessively lenient. This observation is at the root of the rule of precedent, known as stare decisis.Stare decisis forces Courts to weigh the benefits of leniency towards the current parties against the beneficial effects that tougher decisions have on future ones.We study these dynamics and find that stare decisis guarantees that precedents evolve towards ex-ante efficient decisions, thus alleviating the Courts' time-inconsistency problem. However, the dynamics do not converge to full efficiency.     

Optimal limited authority for principal

This article studies a principal-agent problem where the only commitment for the uninformed principal is to restrict the set of decisions she makes following a report by the informed agent. We show that an ex ante optimal equilibrium for the principal corresponds to a finite partition of the state space, and each retained decision is ex post suboptimal for the principal, biased toward the agent?s preference. Generally an optimal equilibrium does not maximize the number of decisions the principal can credibly retain. Compared to no commitment, limited authority improves the quality of communication from the agent. As a result, it can give the principal a higher expected payoff than delegating the decision to the agent.     

Fiscal policy rules,budget deficits,and forecasting biases

In this paper, we analyze the impact fiscal policy rules have on budget deficits and forecasting biases in official budget outlooks. Persistent budget deficits and over-optimistic budget forecasts have been observed in many countries in the past, especially in the euro area. To prevent such developments from happening in the future, fiscal rules have been revised or implemented with the aim to strengthen both preventive (ex-ante) and corrective (ex-post) elements of fiscal rules frameworks. Do such ex-ante and ex-post rules differ in their effects? In an attempt to answer this question, we build a two-period model and distinguish between ex-ante rules that apply to budget forecasts and ex-post rules that apply to realized budget deficits. Our model indicates that effectively enforced ex-post rules are more effective than ex-ante rules at reducing budget deficits. Interestingly, ex-ante rules differ from ex-post rules in their effects on forecasting biases. Only ex-post sanctions reduce forecasting biases, while ex-ante rules have no impact on such biases. In addition, we show that political stability and the size of government increase the effectiveness of fiscal rules. If, however, financial markets have a disciplining effect on governments, the effectiveness of fiscal rules is reduced. Our results imply that if fiscal policy rules cannot be effectively enforced, reforming other areas such as electoral rules or financial market regulations might be a more promising approach to ensuring sound public finances than fiscal policy rules.     

算法合谋的反垄断规制及工具创新研究

在数字经济领域,数字商务企业采用算法定价会明显提高合谋的可能性和可实施性,具有较大的价格合谋风险,因而成为反垄断法关注的重点。学理上,尚待明确的问题有:算法定价促进合谋的内在机理和类型化机制;如何创新反垄断执法体制以有效规制自主学习算法;在反垄断事后执法无效情况下,是否需要以及如何实行事前规制等。研究表明:算法合谋的反垄断规制宜坚持分类治理原则,采取事后反垄断禁止为主并辅之以事前规制的政策组合,反垄断政策工具创新应主要针对自主学习算法合谋。算法合谋反垄断规制政策需重新界定构成非法合谋的"协议"要件,明确当事企业的主体责任,重在采取以"软执法"为主的反垄断执法体制。事前规制政策应坚持"基于设计来遵守法律"的原则,强化算法审查机制和审查能力建设,并将提升算法透明度和可问责性作为重点。     

Incentives and public inputs

Considered in this paper is a mechanism to coordinate the decision to provide a public input to a group of firms designed to overcome the ‘free rider’ problem. The coordinating agent relies on information communicated by the firms and it is shown that the mechanism provides an incentive for each firm to send truthful information so that an optimal quantity of the public input will be provided.     

Non-Dummy Agents in Pure Exchange Economies

We introduce a very fundamental and important axiom of the non-dummy. This states that each agent can change the outcome of the mechanism at some preference profile, thus guaranteeing every agent the minimum right to affect the social decision. We study the possibility of strategy-proof, efficient and non-dummy mechanisms in pure exchange economies. We provide two new interesting classes of such mechanisms. The results shed light on the structure of strategy-proof and efficient mechanisms, and should promote a complete characterization of those mechanisms in pure exchange economies with three or more agents.     

Collective decisions with interdependent valuations

Many collective decision problems have in common that individuals’ desired outcomes are correlated but not identical. This paper studies collective decisions with private information about desired policies. Each agent holds private information which mainly concerns his own bliss point, but private information also affects all other agents. We concentrate on two specific mechanism, the median and mean mechanisms establish the existence of symmetric Bayesian Nash equilibria of the corresponding games and compare the performance of the mechanisms for different degrees of interdependencies. Applications of our framework include the provision of public goods and the design of decision processes in international organizations.