Weakest-link public goods: Giving in-kind or transferring money

This paper extends the analysis of weakest-link public goods, whose level equals the smallest of the agents’ provision levels, by permitting an agent either to increase one's own provision or else augment both one's own provision and that of the other agent(s). Nash equilibria may be either symmetric with agents matching one another's provision or else asymmetric with an in-kind transfer by one agent to another. An equilibrium with cash transfers, but no in-kind transfers, may be Pareto superior to one with only in-kind transfers. If agents differ in their efficiency, then in-kind transfers by the low-cost agent may dominate a cash transfer. The possibility of Pareto-improving transfers is enhanced as the number of agents increases.     

Information,trade and common knowledge

In any voluntary trading process, if agents have rational expectations, then it is common knowledge among them that the equilibrium trade is feasible and individually rational. This condition is used to show that when risk-averse traders begin at a Pareto optimal allocation (relative to their prior beliefs) and then receive private information (which disturbs the marginal conditions), they can still never agree to any non-null trade. On markets, information is revealed by price changes. An equilibrium with fully revealing price changes always exists, and even at other equilibria the information revealed by price changes “swamps” each trader's private information.     

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.     

A note on capital markets and bankruptcy constraints in contracting

This note considers the extent to which state-contingent bankruptcy constraints in a standard contracting problem with adverse selection can be mitigated by a risk-neutral third party. It shows that if payoffs of principal and agent are quasi-linear, the third party can only affect the constraints if it has complete information about the agent's type — observing a correlated signal is not enough.     

Codetermination,Price Competition and the Network Industry

This research develops a tractable two‐stage non‐cooperative game with complete information describing the behaviour of price‐setting firms that must choose to be profit maximisers or bargainers under codetermination in a network industry with horizontal product differentiation. The existing theoretical literature has already shown that codetermination might arise as the endogenous market outcome in a strategic competitive quantity‐setting duopoly. In sharp contrast with this result, the present article shows that codetermination does never emerge as a Nash equilibrium in a price‐setting non‐network duopoly. Then, it aims at highlighting the role of network externalities in determining changes of paradigm of the game and letting codetermination become a sub‐game perfect Nash equilibrium when prices are strategic substitutes or strategic complements. This equilibrium may be Pareto efficient. Results allow distinguishing between mandatory codetermination and voluntary codetermination. The article also proposes a model of endogenous codetermination according to which every firm may choose to bargain with its own corresponding union bargaining unit only whether the firm's bargaining strength is exactly the profit‐maximising one. The equilibrium outcomes emerging in this case range from a uniform Nash equilibrium, in which both firms are codetermined, to mixed Nash equilibria, in which only one of them chooses to be codetermined. These results are ‘network depending’ and do not hold in a non‐network duopoly.     

Secure implementation experiments: Do strategy-proof mechanisms really work?

Strategy-proofness, requiring that truth-telling is a dominant strategy, is a standard concept used in social choice theory. Saijo, Sjöström and Yamato [Saijo, T., Sjöström, T., Yamato, T., 2003. Secure implementation: Strategy-proof mechanisms reconsidered. Working paper 4-03-1. Department of Economics, Pennsylvania State University] argue that this concept has serious drawbacks. In particular, many strategy-proof mechanisms have a continuum of Nash equilibria, including equilibria other than dominant strategy equilibria. For only a subset of strategy-proof mechanisms do the set of Nash equilibria and the set of dominant strategy equilibria coincide. For example, this double coincidence occurs in the Groves mechanism when preferences are single-peaked. We report experiments using two strategy-proof mechanisms. One of them has a large number of Nash equilibria, but the other has a unique Nash equilibrium. We found clear differences in the rate of dominant strategy play between the two.     

On some alternative criteria for justice between generations

This paper is concerned with Rawls' principle of just savings. Both the intergenerational maxi–min solution and the Nash equilibrium are analyzed in the context of a simple growth model and a specific preference structure. The results are compared to the Utilitarian solution. The maxi–min solution is intertemporally inconsistent and all the Nash equilibria are Pareto inefficient. The latter part of the paper analyzes intergenarational strong equilibria, the α-core and the β-core. It is shown that for the model in question the set of strong equilibria is empty, and that both the α- and β-cores are roughly speaking equal to the set of all Pareto efficient programmes of accumulation.     

Secure implementation experiments: Do strategy-proof mechanisms really work?

Strategy-proofness, requiring that truth-telling is a dominant strategy, is a standard concept used in social choice theory. Saijo, Sjöström and Yamato [Saijo, T., Sjöström, T., Yamato, T., 2003. Secure implementation: Strategy-proof mechanisms reconsidered. Working paper 4-03-1. Department of Economics, Pennsylvania State University] argue that this concept has serious drawbacks. In particular, many strategy-proof mechanisms have a continuum of Nash equilibria, including equilibria other than dominant strategy equilibria. For only a subset of strategy-proof mechanisms do the set of Nash equilibria and the set of dominant strategy equilibria coincide. For example, this double coincidence occurs in the Groves mechanism when preferences are single-peaked. We report experiments using two strategy-proof mechanisms. One of them has a large number of Nash equilibria, but the other has a unique Nash equilibrium. We found clear differences in the rate of dominant strategy play between the two.     

Incomplete information and singleton cores in matching markets

We study ordinal Bayesian Nash equilibria of stable mechanisms in centralized matching markets under incomplete information. We show that truth-telling is an ordinal Bayesian Nash equilibrium of the revelation game induced by a common belief and a stable mechanism if and only if all the profiles in the support of the common belief have singleton cores. Our result matches the observations of Roth and Peranson [The redesign of the matching market for American physicians: some engineering aspects of economic design, Amer. Econ. Rev. 89 (1999) 748-780] in the National Resident Matching Program (NRMP) in the United States: (i) the cores of the profiles submitted to the clearinghouse are small and (ii) while truth-telling is not a dominant strategy most participants in the NRMP truthfully reveal their preferences.     

Buried in paperwork: Excessive reporting in organizations

This paper offers an explanation for why a principal may demand too much paperwork from a subordinate: due to limited liability and moral hazard a principal is unable to appropriate all rents. Internal paperwork allows a more accurate monitoring of the agent and enables the principal to appropriate a larger part of the agent’s rent. In her decision the principal disregards the agent’s cost increase of more internal paperwork. Consequently, the requested amount of internal paperwork may be too high from both the agent’s personal point of view and the organization as a whole.     

Cost Sharing under Increasing Returns: A Comparison of Simple Mechanisms

A technology with decreasing marginal costs is used by agents with equal rights. Each agent demands a quantity of output and costs are divided by means of a fixed formula. Several such mechanisms are compared for the existence of Nash equilibrium demand profiles and for the equity properties of these equilibria. Among three mechanisms, average cost pricing, the Shapley–Shubik cost sharing, and serial cost-sharing, only the latter two possess at least one Nash equilibrium on a reasonable domain of individual preferences. Only the serial cost sharing equilibria pass the equity tests of No Envy and Stand Alone cost.Journal of Economic LiteratureClassification Numbers: C72, D63.     

Constrained public goods in networks

This paper analyses the private provision of public goods where agents interact within a fixed network structure and may benefit only from their direct neighbours’ provisions. We generalise the public goods in the networks model of Bramoullé and Kranton [J. Econ. Theory 135 (2007), pp. 478–494] to allow for constrained provision. In so doing, we characterise Nash equilibria with no intermediate contributors.     

Implementing efficient graphs in connection networks

We consider the problem of sharing the cost of a network that meets the connection demands of a set of agents. The agents simultaneously choose paths in the network connecting their demand nodes. A mechanism splits the total cost of the network formed among the participants. We introduce two new properties of implementation. The first property, Pareto Nash implementation (PNI), requires that the efficient outcome always be implemented in a Nash equilibrium and that the efficient outcome Pareto dominates any other Nash equilibrium. The average cost mechanism and other asymmetric variations are the only mechanisms that meet PNI. These mechanisms are also characterized under strong Nash implementation. The second property, weakly Pareto Nash implementation (WPNI), requires that the least inefficient equilibrium Pareto dominates any other equilibrium. The egalitarian mechanism (EG) and other asymmetric variations are the only mechanisms that meet WPNI and individual rationality. EG minimizes the price of stability across all individually rational mechanisms.     

Incentives for motivated agents under an administrative constraint

Consider an agent who has an expertise in producing a non-marketable good. This good is valued by a single principal, and there is a verifiable measure of the agent’s performance. Crucially, the agent is intrinsically motivated due to ‘warm glow altruism’. In addition, the agent’s budget, which is controlled by the principal, must not be less than the monetary performance-cost faced by the agent. This gives rise to a limited-liability constraint. It also restricts the agent’s ability to under-report costs. In such environment, we determine the link between the agent’s budget and performance. Our results come in contrast to the received solution of the principal-agent problem and to most in the literature on mission-motivated organisations and public services provision.     

Optimal information acquisition and monetary policy

I study optimal monetary policy with an expectational AS curve and private agents who optimally choose their amount of information pertinent to predicting policy. Shocks with time-varying variance (ARCH) induce interesting information acquisition (IA) dynamics; optimal IA affects optimal policy and vice versa. Under discretion, IA dynamics cause time-varying effectiveness of policy because of the expectational AS curve; policy may be rendered completely ineffective. In policy game equilibrium, a fall in the shock’s variance typically induces less IA and raises welfare. In one exceptional case the opposite occurs, a result which does not require implausible unstable equilibria. An agent becoming informed increases the endogenous component of economic volatility; IA therefore has a negative externality. Under commitment policy’s effectiveness is again time-varying, but policy is never completely ineffective: commitment enables the central bank to credibly limit policy’s volatility; this limits private agents’ incentive to become informed, so limits expectation-induced policy neutrality.     

A theory of cooperation in games with an application to market socialism

Abstract

Economic theory has focused almost exclusively on how humans compete with each other in their economic activity, culminating in general equilibrium (Walras–Arrow–Debreu) and game theory (Cournot–Nash). Cooperation in economic activity is, however, important, and is virtually ignored. Because our models influence our view of the world, this theoretical lacuna biases economists’ interpretation of economic behavior. Here, I propose models that provide micro-foundations for how cooperation is decentralized by economic agents. It is incorrect, in particular, to view competition as decentralized and cooperation as organized only by central diktat. My approach is not to alter preferences, which is the strategy behavioral economists have adopted to model cooperation, but rather to alter the way that agents optimize. Whereas Nash optimizers view other players in the game as part of the environment (parameters), Kantian optimizers view them as part of action. When formalized, this approach resolves the two major failures of Nash optimization from a welfare viewpoint – the Pareto inefficiency of equilibria in common-pool resource problems (the tragedy of the commons) and the inefficiency of equilibria in public-good games (the free rider problem). An application to market socialism shows that the problems of efficiency and distribution can be completely separated: the dead-weight loss of taxation disappears.     

Informed principal with correlation

In this paper we analyze an adverse selection model with one principal and one agent, who are both risk neutral and have private information. We assume that the private information of the principal is correlated with that of the agent. The main result of the paper is that the principal can extract a larger share of the surplus from the agent than in the case where her information is public. The principal can design such a contract because she exploits the fact that her type is an informative signal on the agent's one. We fully characterize the equilibrium of the game in which different types of principal offer the same menu of contracts that leaves the agent uninformed about the principal's type. This gives more freedom to the principal when setting the transfers because the agent's constraints need to hold only at an interim stage.     

IRRATIONALITY‐PROOFNESS: MARKETS VERSUS GAMES

How robust are economic models to the introduction of irrational agents? The Pareto efficiency of competitive equilibria is not robust since one irrational agent leads to inefficiency. But the property that rational agents cannot use their own resources to Pareto improve on their competitive allocation holds regardless of the number of irrational agents. Full production efficiency can be robust as well, but irrational firms introduce a trade‐off between efficiency and the attainment of Pareto improvements. Regarding games, I show that while existing implementation mechanisms are sensitive to the presence of irrational agents, there are robust alternatives with attractive welfare properties.     

Competition between asymmetrically informed principals

Summary. This paper derives the set of equilibria for common agency games in which the principals compete in piece rates and lump sum payments and one principal has incomplete information about the agent's preferences. We show that the uninformed principal's expected payoff function is discontinuous with respect to the identity of the marginal agent type. This discontinuity is shown to support an open set of equilibria. For games in which the first-best equilibrium strategies are measurable with respect to the uninformed principal's information partition, this result implies the existence of an open set of Pareto inefficient equilibria. Received: December 5, 1995; revised version August 18, 1996     

When Does Everyone Contribute in the Private Provision of Local Public Goods?

When does everyone genuinely contribute in the private provision of a local public good? We first introduce a monotonic condition to characterize the relationship between the structure of the network that underlie the noncooperative game of private provision of local public goods on the one hand, and the preferences of the agents on the other, showing that the monotonic condition is a sufficient and necessary condition of existence of a distributed Nash equilibrium (DNE) in which each agent exerts a positive amount of effort to provision of the public good (Theorem 1). We then study the number of equilibria, and, by using the monotonic condition, characterize the condition under which the DNE set is a singleton, a continuum, or null (Theorem 2). As it turns out, the structure of the network and the agents’ preferences jointly shape the effort profile in the provision of local public goods.