Dynamic coalitional equilibrium

We study coalition formation processes of Konishi and Ray (2003) [27]. It is shown that an absorbing and deterministic process of coalition formation that also forms an equilibrium - satisfies a coalitional one-deviation property - does exist if one allows the process to be history dependent. All such dynamic equilibrium processes of coalition formation are characterized. Absorbing outcomes of dynamic equilibrium processes are also identified. It is shown that they always constitute a subset of the largest consistent set of Chwe (1994) [11]. A procedure that identifies a dynamic equilibrium process of coalition formation in finite time is constructed.     

Optimal design of pension funds: a mission impossible?

Summary. Nowadays many employers offer their employees the possibility of an insurance against too large losses in income when retiring or becoming disabled. This paper models the optimization problem of the employer when setting up such a so-called pension fund. Not surprisingly, it turns out that the optimal solution depends on the premium the employees are willing to pay at most for such an insurance. Since this is private information for an employee and hence not known to the employer, he needs to collect information regarding these maximum premiums. It is shown that if employees' characteristics only differ in the maximum premium they are willing to pay, the employer is unable to perfectly inform himself on these maximum premiums, i.e. he cannot create the right incentives for his employees to reveal their maximum premiums truthfully. Received: March 20, 2000; revised version: March 11, 2002 RID="*" ID="*" The authors acknowledge the helpful comments and suggestions of an anonymous referee. The research of J. Suijs is made possible by a fellowship of the Royal Netherlands Academy of Arts and Sciences (KNAW). Correspondence to: J. Suijs     

Conceptions of property rights and norms

The social norm literature in law and economics fails to account for the differences between the two major conceptions of property rights. The differences between the two conceptions affect people’s utility function by affecting how increases in property rights are perceived. This paper discusses how the modern, in rem, conception evolved from an older, in personam, conception; it also discusses how economics has absorbed the modern, in rem, conception. The paper demonstrates that if people do not perceive the benefits of modern property rights, they will follow their social norms if the government or planner imposes modern property rights on them. In the end, this allows one to make a fuller discussion of why norms economize information. This discussion has various consequences ranging from developmental economics to financial market economics and cannot be ignored.

The small worlds axiom for stable equilibria

The small worlds axiom was introduced in J. F. Mertens (Math. Oper. Res. 16, (1991)) with the meaning that, if the payoffs to a subset of the players are unaffected by the actions of the outsiders (or if just their best reply correspondence is unaffected), the solutions (the stable sets) of the game between insiders are exactly the projections of the solutions of the larger game. We prove this property here for q-stable sets, for any characteristic q.     

Self-Fulfilling Mechanisms in Bayesian Games

Amechanismfor a Bayesian gameGis a mapping μ from the set of states of nature to the set of players' actions. μ isself-fulfillingif players are truthful at the communication stage and, given the information revealed by μ, no player can gain in unilaterally deviating from the action prescribed by the mechanism. We investigate the properties of self-fulfilling mechanisms and we show in particular that they correspond to inert solutions of the infinitely repeated game generated byG. We also discuss applications to market games, regulation, and R&D games.Journal of Economic LiteratureClassification Numbers: D82, C72.     

The Issue of Efficiency and the Role of State in New Institutional Economics: A Critical Perspective

ABSTRACT

This article scrutinises and criticises the notion of efficiency and the role of state in the emergence and evolution of institutions and property rights within the tradition of new institutional economics. Specifically, the attempt is to criticise the efficiency view of the formation of property rights and institutions. It is shown that the efficiency concept cannot provide a sufficient rationale for explaining the origins of private property. Additionally, some recent developments of North's thought are critically scrutinised, showing that his theoretical apparatus could be conceived as a paradise for the eclectic. Further, the role of the state in different versions of the theory of property rights – with a special reference to North's treatment of the notion of state – is, also, critically examined. Although North’s work has virtues compared to the ‘naïve model’ of property rights by recognising and addressing the role of the state and the issue of power in the formation of property rights and institutions, he does not succeed in fully accounting for the existence of institutional arrangements, due to his adherence to an individualist framework.     

Reciprocal relationships and mechanism design

We study an incomplete information game in which players can coordinate their actions by contracting among themselves. We model this relationship as a reciprocal contracting procedure where each player has the ability to make commitments contingent on the other players' commitments. We differ from the rest of the literature on reciprocal contracting by assuming that punishments cannot be enforced in the event that cooperation breaks down. We fully characterize the outcomes that can be supported as perfect Bayesian equilibrium outcomes in such an environment. We use our characterization to show that the set of supportable outcomes with reciprocal contracting is larger than the set of outcomes available in a centralized mechanism design environment in which the mechanism designer is constrained by his inability to enforce punishments against non‐participants. The difference stems from the players' ability in our contracting game to convey partial information about their types at the time they offer contracts. We discuss the implications of our analysis for modelling collusion between multiple agents interacting with the same principal.     

Proper belief revision and equilibrium in dynamic games

We present a theory of rationality in dynamic games in which players, during the course of the game, may revise their beliefs about the opponents’ utility functions. The theory is based upon the following three principles: (1) the players’ initial beliefs about the opponents’ utilities should agree on some profile u of utility functions, (2) every player should believe, at each of his information sets, that his opponents are carrying out optimal strategies and (3) a player at information set h should not change his belief about an opponent's ranking of strategies a and b if both a and b could have led to h. Scenarios with these properties are called preference conjecture equilibria for the profile u of utility functions. We show that every normal form proper equilibrium for u induces a preference conjecture equilibrium for u, thus implying existence of preference conjecture equilibrium.     

Infinite horizon common interest games with perfect information

We consider infinite horizon common interest games with perfect information. A game is a K-coordination game if each player can decrease other players' payoffs by at most K times his own cost of punishment. The number K represents the degree of commonality of payoffs among the players. The smaller K is, the more interest the players share. A K-coordination game tapers off if the greatest payoff variation conditional on the first t periods of an efficient history converges to 0 at a rate faster than K^−t as t→∞. We show that every subgame perfect equilibrium outcome is efficient in any tapering-off game with perfect information. Applications include asynchronously repeated games, repeated games of extensive form games, asymptotically finite horizon games, and asymptotically pure coordination games.     

Second price auctions on general preference domains: two characterizations

Auction theory usually assumes the quasi-linearity of individual preferences. We drop this assumption and define an extension of second price mechanisms that applies to general preferences. It turns out that the extended second price mechanisms are the only rules satisfying efficiency, strategy-proofness, and a mild non-imposition property. Their definition is simple just as much as the definition of usual second price mechanisms: everyone reports his maximum willingness to pay and the bidder whose reported value is highest buys the auctioned object for the price equal to the second highest reported value. The characterization is valid if efficiency is replaced by envy-freeness. I gratefully acknowledge an associate editor and two anonymous referees for their very helpful comments. Hiroki Saitoh and Shigehiro Serizawa independently obtain a result that is closely related to my main result (see, Remark in Sect. 1). I thank them for sending me the paper and communication, and Yuji Fujinaka for informing me about their work. I also thank the financial support by KAKENHI (19310031).     

Uncertainty and the Voluntary Provision of a Pure Public Good in a Two‐Moment Decision Model

In this paper, we explore the potential benefits of uncertainty that may arise in a two‐moment model of the voluntary provision of a pure public good. We find that an increase in a given contributor i’s risk associated with the aggregate contribution level of the other contributors (i.e., an increase in social uncertainty) induces that contributor to increase his own contribution level if and only if the uncertainty's incremental effect on the expected value of his net marginal utility is negative. Contributor i’s welfare likewise increases when a closely related condition is met, namely that the uncertainty's marginal effect on his expected marginal utility value of the public good exceeds its countervailing effect on the numeraire. Further, the corresponding aggregate contribution to the public good increases in the presence of free‐riding if and only if the incremental effect of contributor i’s contribution on the aggregate expected value of all other contributors’ net marginal utilities is small‐enough positive. We derive similar conditions for the case of private uncertainty, where the increase in contributor i’s risk is associated with his own marginal valuation of the public good. A simple example illustrates these conceptual results. Numerical analysis demonstrates that an increase in private uncertainty can have a nonmonotonic impact on contributor i’s welfare.     

Social learning and costly information acquisition

Summary. Short-lived agents want to predict a random variable q\theta and have to decide how much effort to devote to collect private information and consequently how much to rely on public information. The latter is just a noisy average of past predictions. It is shown that costly information acquisition prevents an unbounded accumulation of public information if (and only if) the marginal cost to acquire information is positive at zero (C￠(0) > 0)(C^\prime (0) > 0). When C￠(0) = 0C^\prime (0) = 0 public precision at period n, _boxclose_boxclose\tau_n, tends to infinity with n but the rate of convergence of public information to q\theta is slowed down with respect to the exogenous information case. At the market outcome agents acquire too little private information. This happens either with respect to a (decentralized) first best benchmark or, for n large, with respect to a (decentralized) second best benchmark. For high discount factors the limit point of market public precision always falls short of the welfare benchmarks whenever C￠(0) > 0C^\prime (0) > 0. In the extreme, as the discount factor tends to one public precision tends to infinity in the welfare-optimal programs while it remains bounded at the market solution. Otherwise, if C￠(0) = 0C^\prime (0) = 0 public precision accumulates in an unbounded way both at the first and second best solutions. More public information may hurt at either the market or second best solutions.     

Candidate stability and probabilistic voting procedures

Summary. We extend the analysis of Dutta, Jackson and Le Breton (Econometrica, 2001) on strategic candidacy to probabilistic environments. For each agenda and each profile of voters preferences over running candidates, a probabilistic voting procedure selects a lottery on the set of running candidates. Assuming that candidates cannot vote, we show that random dictatorships are the only unanimous probabilistic voting procedures that never provide unilateral incentives for the candidates to withdraw their candidacy at any set of potential candidates. More flexible probabilistic voting procedures can be devised if we restrict our attention to the stability of specific sets of potential candidates.Received: 4 February 2003, Revised: 14 September 2004, JEL Classification Numbers: D71, D72.This is a revised version of a chapter of my Ph.D. Dissertation submitted to the Universitat Autónoma de Barcelona. I am indebted to my supervisor Salvador Barberá for his advice and constant support. I am grateful to Dolors Berga and an anonymous referee for their detailed comments and suggestions. I thank José Alcalde, Walter Bossert, Bhaskar Dutta, Lars Ehlers, Jordi Massó, Diego Moreno, Clara Ponsatí, Yves Sprumont, and William Thomson for many helpful comments and discussions. I thank the hospitality of the C.R.D.E. at the Université de Montréal and the Department of Economics of the University of Warwick where parts of this research were conducted. Financial support through Research Grant 1998FI00022 from Comissionat per Universitats i Recerca, Generalitat de Catalunya, Research Project PB98-870 from the Ministerio de Ciencia y Tecnología, and Fundación Barrié de la Maza is gratefully acknowledged.     

Money in the pure consumption loan model

The purpose of this paper is to show how modern techniques of Temporary competitive equilibrium analysis can be applied to models of the “pure consumption loan model” type. One considers Samuelson's simplest model where traders live two periods and where money is the only store of value. It is proved that a temporary equilibrium exists if price expectations are sufficiently independent of current prices. A stationary market equilibrium is shown to exist if there is a set of traders (i) whose total resources are greater when they are young than when they are old, (ii) who are indifferent between present and future consumption. It is proved that this existence theorem still holds if the economy is sufficiently “close” to an economy which has this property. A stationary market equilibrium is shown to be Pareto optimal if all traders hold positive cash balances. It may be inefficient if this condition is not satisfied, for some traders may then be willing to borrow, which they cannot do in this model.     

Sentiments and Motivations in Adam Smith and Vernon Smith

Vernon Smith (VS) discovered Adam Smith (AS) late in his professional career, and has adopted ideas from The Theory of Moral Sentiments to explain findings in experimental economics. Most important is the theorized link between moral sentiments and the evolution of property rights and law as foundations for commerce. VS's encounter with AS, while not new, provides a compelling look at the modern laboratory of social science through the lens of the Enlightenment, and cannot easily be encapsulated within a utilitarian framework. This paper provides an overview and commentary on VS's approach.     

Half empty, half full and why we can agree to disagree forever

Aumann [Aumann R., 1976. Agreeing to disagree. Annals of Statisitics 4, 1236–1239] derives his famous we cannot agree to disagree result under the assumption that people are expected utility (=EU) decision makers. Motivated by empirical evidence against EU theory, we study the possibility of agreeing to disagree within the framework of Choquet expected utility (=CEU) theory which generalizes EU theory by allowing for ambiguous beliefs. As our first main contribution, we show that people may well agree to disagree if their Bayesian updating of ambiguous beliefs is psychologically biased in our sense. Remarkably, this finding holds regardless of whether people with identical priors apply the same psychologically biased Bayesian update rule or not. As our second main contribution, we develop a formal model of Bayesian learning under ambiguity. As a key feature of our approach the posterior subjective beliefs do, in general, not converge to “true” probabilities which is in line with psychological evidence against converging learning behavior. This finding thus formally establishes that CEU decision makers may even agree to disagree in the long-run despite the fact that they always received the same information.     

Minimum Memory for Equivalence between Ex Ante Optimality and Time-Consistency

I give a necessary and sufficient condition on memory of a player in an extensive game for equivalence between ex ante optimality and time-consistency (for all payoff assignments). The condition is called A-loss recall and requires that each loss of a player's memory can be traced back to some loss of memory of his own action. A-loss recall is also shown to be a necessary and sufficient condition for the existence of a time-consistent strategy (for all payoff assignments) if the player is conscious-minded. Journal of Economic Literature Classification Numbers: C72, D80.     

On the macroeconomic effects of establishing tradability in weak property rights

The New Economy is closely associated with computing & communications technology, notably the Internet. We discuss property rights to, and trade in, the difficult-to-define intangible assets increasingly dominating the New Economy, and the possibility of under-investment in these assets. For a realistic analysis we introduce a Schumpeterian market environment (the experimentally organized economy). Weak property rights prevail when the rights to access, use, andtrade in intangible assets cannot be fully exercised. The trade-off between the benefits of open access on the Internet, and the incentive effects of strengthened property rights, depend both on the particular strategy a firm employs to secure property rights, and the protection offered by law. Economic property rights can be strengthened if the originator can find innovative ways to charge for the intangible assets. The extreme complexity of the New Economy and the large number of possible innovative private contract arrangements make it more important to facilitate the use and enforcement of private individualized contracts to protect intellectual property than to rely only on standard patent and copyright law. Enabling law is one proposed solution. Current patent legislation in the US has led to costly litigation processes weakening the position of small firms and individuals in patent disputes. The property rights of such firms and individuals could be strengthened with insurance or arbitration procedures.JEL Classification: D21, D23, D52, D82, H54, K11, K22, K41, L11, L23, M13, O14, O33An earlier version of this paper was presented at the 9th Congress of the International Joseph A. Schumpeter Society (ISS), Gainesville, Florida, USA, March 28-30, 2002. The paper is part of the Nödfor project on Schumpeterian Creative Destruction, notably the exit and bankruptcy process, based at the Ratio Institute, Stockholm.     

An investigation of regime shifts in UK commercial property returns: a time series analysis

The random-walk hypothesis, vis-à-vis asset price, suggests that prices traded in a market cannot be predicted based on historical information. Employing unsecuritized UK commercial property returns, we analyse this hypothesis by investigating regime shifts or multiple changes in persistence in the series. Our results uncover regime shifts in both the aggregate and sector-specific data. Specifically, the shifts are less frequent in the Industrial sector, compared to the Office, Retail and Aggregate returns data. We highlight some implications for academics, practitioners and regulators.     

The Partnered Core of a Game without Side Payments

A payoff for a game is partnered if it admits no asymmetric dependencies. We introduce the partnered core of a game without side payments and show that the partnered core of a balanced game is nonempty. The result is a strengthening of Scarf's Theorem on the nonemptiness of the core of a balanced game without side payments. In addition, it is shown that if there are at most a countable number of points in the partnered core of a game then at least one core point isminimallypartnered, meaning that no player requires any other player in particular to obtain his part of the core payoff.Journal of Economic LiteratureClassification Number: C71.