Government policy and the probability of coordination failures

This paper introduces an approach to the study of optimal government policy in economies characterized by a coordination problem and multiple equilibria. Such models are often criticized as not being useful for policy analysis because they fail to assign a unique prediction to each possible policy choice. We employ a selection mechanism that assigns, ex ante, a probability to each equilibrium indicating how likely it is to obtain. We show how such a mechanism can be derived as the natural result of an adaptive learning process. This approach leads to a well-defined optimal policy problem, and has important implications for the conduct of government policy. We illustrate these implications using a simple model of technology adoption under network externalities.     

Optimal taxation in a stochastic economy: A Cobb–Douglas example

Optimal linear and two-piece linear taxes are calculated in two-period economies in which individuals face uncertainty about their ability to work in the second period. These second-best insurance/redistribution programs are compared with first-best economies, equilibria without government intervention, and analogous determinate economies having the same ex post production possibilities. The calculations point out ways in which economies with individual uncertainty differ from those without it.     

A progress report on Kelly's majority conjectures

LetC(m, n) be the proportion of n-voter profiles on m alternatives that have a majority winner. Jerry Kelly conjectured that C(m, n) > C(m + 1, n) for m ? 3 and n = 3 and n ? 5, and C(m, n) > C(m, n + 2) for m ? 3 and n ? 3. We prove these for special cases.     

Ex ante contracting with endogenously determined communication plans

Summary. In this paper we introduce a new model of ex ante contracting for economies with asymmetric information to examine endogenously determined communication plans for information sharing in the interim stage. In contrast to the models used in previous research, in the present model agents negotiate not only on a contract of state contingent allocations but also on a communication plan, a set of rules describing how agents will reveal part of their private information at the interim stage to execute the trade contracts. We prove a result about the nested structure of the set of allocations implementable by various communication plans and establish the existence of core strategies for this cooperative game under various regularity conditions. Received: 4 March 1998; revised version: 17 September 1999     

Ex ante efficiency implies incentive compatibility

We show that when agents become informationally negligible in a large economy with asymmetric information, every ex ante efficient allocation must be incentive compatible. This means that any ex ante core or Walrasian allocation is incentive compatible. The corresponding result is false for fixed finite-agent economies with asymmetric information. An example is also constructed to show that the ex post version of the result does not hold. Furthermore, we show that the result is sharp in the sense that it will fail to hold if one relaxes any of the main assumptions, namely, strong conditional independence on the information structure, strict concavity on the utility functions, type independence on the utility functions and endowments.      

Optimal selling strategies when buyers may have hard information

Consider a revenue-maximizing seller who can sell an object to one of n potential buyers. Each buyer either has hard information about his valuation (i.e., evidence that cannot be forged) or is ignorant. The optimal mechanism is characterized. It turns out that more ignorance can increase the expected total surplus. Even when the buyers are ex ante symmetric, the object may be sold to a buyer who does not have the largest willingness-to-pay. Nevertheless, an additional buyer increases the expected total surplus in the symmetric case, whereas more competition can be harmful if there are ex ante asymmetries.     

Iterated Weak Dominance in Strictly Competitive Games of Perfect Information

We prove that any strictly competitive perfect-information two-person game with n outcomes is solvable in n−1 steps of elimination of weakly dominated strategies— regardless of the length of the game tree. The given bound is shown to be tight using a variant of Rosenthal's centipede game. Journal of Economic Literature Classification Numbers: C70, C72.     

General equilibrium in economies with uncertain delivery

We consider a general equilibrium model of trade ex ante with differential information in which agents choose plans of state-contingent lists of bundles. Being unable to verify that the state of nature is s and not t, an agent has to accept the delivery of any bundle in the list for delivery in state s or in the list for delivery in state t. Under the assumption that each state of nature can be verified by at least one agent, we establish existence of equilibrium and we show that the equilibrium allocation satisfies a notion of coalitional incentive compatibility.     

An Axiomatization of Nash Equilibria in Economic Situations

We consider the class of all abstract economies with convex and compact strategy sets, continuous and quasi-concave payoff functions, and continuous and convex-valued feasibility correspondences. We prove that the Nash correspondence is the unique solution on the foregoing class of abstract economies that satisfies nonemptiness, rationality in one-person economies, and consistency.Journal of Economic LiteratureClassification Numbers: C72, D50.     

Second-best efficiency of allocation rules: strategy-proofness and single-peaked preferences with multiple commodities

We study strategy-proof allocation rules in economies with perfectly divisible multiple commodities and single-peaked preferences. In this setup, it is known that the incompatibility among strategy-proofness, Pareto efficiency and non-dictatorship arises in contrast with the Sprumont (Econometrica 59:509–519, 1991) one commodity model. We first investigate the existence problem of strategy-proof and second-best efficient rules, where a strategy-proof rule is second-best efficient if it is not Pareto-dominated by any other strategy-proof rules. We show that there exists an egalitarian rational (consequently, non-dictatorial) strategy-proof rule satisfying second-best efficiency. Second, we give a new characterization of the generalized uniform rule with the second-best efficiency in two-agent case.     

Unit Versus Ad Valorem Taxes: The Private Ownership of Monopoly in General Equilibrium

Employing a general equilibrium framework, Blackorby and Murty prove that, with a monopoly and under 100% profit taxation and uniform lump‐sum transfers, the utility possibility sets of economies with unit and ad valorem taxes are identical. This welfare equivalence is in contrast to most previous studies, which demonstrate the superiority of the ad valorem tax in a partial equilibrium framework. In this paper, we relax the assumption of 100% profit taxation and allow the consumers to receive profit incomes from ownership of shares in the monopoly firm. We find that, under certain regularity conditions, for any fixed vector of profit shares, the utility possibility sets of economies with unit and ad valorem taxes are not generally identical. But it does not imply that one completely dominates the other. Rather, the two utility possibility frontiers cross each other. Additionally, employing a standard partial equilibrium welfare analysis, we show that the Marshallian social surpluses resulting from the two tax structures are identical when the government can implement unrestricted transfers.     

Core allocations and the dimension of the cone of efficiency price vectors

Let (R₁,…,R_k) be an arbitrary partition of the grand coalition in an atomless exchange economy with k “large enough.” We prove that an optimal allocation x belongs to the core if and only if x cannot be improved upon by any coalition that includes at least one of the R_i's. K is “large enough” if k ? r + 1, where r is the linear dimension of the cone P of the efficiency price vectors for x. Recall that it is always true that r ? n, when n is the number of commodities in the market, and that under differentiability and interiority r = 1; thus k can be chosen to be 2 (i.e., for any coalition R, an allocation x belongs to the core of the market if and only if x is not blocked by any coalition that either contains R or contains its complement).     

On the dynamics of inflation persistence around the world

We study the dynamics of inflation persistence in 45 countries for the period 1960–2008 using a recently developed test for multiple changes in persistence, which decomposes the sample information between adjacent I (0) and I (1) periods. We find that: (i) inflation persistence and average inflation tend to fall and rise at the same time; (ii) in some countries there are changes in the level of inflation which do not seem to be related to changes in inflation persistence; (iii) around half of the countries analyzed do not present any burst of I (1) behavior, and hence have stationary inflation throughout; (iv) for the other half, we detect switches of the type I (0) ? I (1) ? I (0), hence, inflation persistence, when it has occurred, has been temporal; and, (v) for about half of the countries in which inflation has presented I (1) behavior, persistent inflation lasted more than a decade. In addition, we find that in the last 50 years there have been mainly two episodes where long bursts of I (1) inflation took place simultaneously among groups of countries. In general, the “Great Inflation” occurred during the seventies and eighties in advanced economies, whereas it occurred during the eighties and nineties in emerging economies, particularly in Latin America.     

Simple sequencing problems with interdependent costs

In this paper we analyze simple sequencing problems under incomplete information and interdependent costs. We prove the necessity of concave cost function for implementability of such problems. Implementability means that one can achieve aggregate cost minimization in ex-post equilibrium. We also show that simple sequencing problems are implementable if and only if the mechanism is a ‘generalized VCG mechanism.’ We then consider first best implementability, that is implementability with budget balancing transfer. We prove that for implementable n agent simple sequencing problems, with polynomial cost function of order (n−2) or less, one can achieve first best implementability. Finally, for the class of implementable simple sequencing problems with “sufficiently well behaved” cost function, this is the only first best class.     

Passing the Buck On the acceptance of responsibility

In the Passing the Buck game, the n members of a group decide in a given order whether or not to incur costs so that they can fix a certain problem for the benefit of the group. Passing the Buck means that one relies on the service of a successor. The decision is influenced by social preferences and by strategic considerations. We derive three main conclusions from experiments with n=3 and n=4. (i) The unique perfect Baysian equilibrium of the Passing the Buck game with incomplete information about the preferences of other players generally fits the data, however with two interesting exceptions. (ii) Backward induction breaks down if it requires more than two steps, i.e., for the first player in the game with n=4. (iii) Making one of the members of the group an “expert” who alone is competent to fix the problem is connected with a change of social preferences.     

Existence of equilibrium in the Helpman–Krugman model of international trade with imperfect competition

Helpman and Krugman (Market structure and foreign trade. Increasing returns, imperfect competition, and the international economy. MIT Press, Cambridge, 1985) provide a synthesis of the traditional factor proportions theory of international trade and the theory of international trade due to the exploitation of scale economies in imperfectly competitive markets. They derive illuminating results about trade patterns and gains from trade, among other things, leaving unanswered the question of existence of equilibrium, however. The central significance of their characterization of properties of free trade equilibria with inter-industry and intra-industry trade calls for an analysis of existence of equilibrium. This is the object of the present paper. We prove the existence of equilibrium for the integrated multi-sector multi-factor Helpman–Krugman economy without national borders. Well-known conditions ensure that the world economy under free trade reproduces this equilibrium and thus establishes existence of a free trade equilibrium. Since an equilibrium of the integrated economy is not necessarily unique, the same holds true for a free trade equilibrium.     

The ministry, plan changes, and the ratchet in planning

Do Soviet planners employ the ratchet, that is, do they increase targets in response to higher performance, as is generally accepted, or has David Granick (J. Comp. Econ., Sept. 1980, pp. 255–273) proved statistically that they do not? This paper tries to show that accepted views of planning behavior are well founded. The evidence comes from two sources: East German data show that targets are adjusted ex post, partly in response to performance; Soviet sources, presumed by Granick to prove the absence of a ratchet, are shown to prove its existence.     

Collective choice under dichotomous preferences

Agents partition deterministic outcomes into good or bad. A mechanism selects a lottery over outcomes (time-shares). The probability of a good outcome is the canonical utility. The utilitarian mechanism averages over outcomes with largest “approval”. It is efficient, strategyproof, anonymous and neutral.We reach an impossibility if, in addition, each agent's utility is at least , where n is the number of agents; or is at least the fraction of good to feasible outcomes. We conjecture that no ex ante efficient and strategyproof mechanism guarantees a strictly positive utility to all agents, and prove a weaker statement.     

Von Neumann-Morgenstern stable sets, discounting, and Nash bargaining

We establish a link between von Neumann-Morgenstern stable set and the Nash solution in a general n-player utility set. The stable set-solution is defined with respect to a dominance relation: payoff vector u dominates v if one player prefers u even with one period delay. We show that a stable set exists and, if the utility set has a smooth surface, any stable set converges to the Nash bargaining solution when the length of the period goes to zero.     

Does High‐skilled Migration Affect Publicly Financed Investments?

This paper analyzes the interaction between migration of high‐skilled labor and publicly financed investment. We develop a theoretical model with multiple, ex ante identical jurisdictions where individuals decide on education and subsequent emigration. Migration decisions are based on differences in net income across jurisdictions which may occur endogenously. The interaction between income differences and migration flows gives rise to the potential of multiple equilibria: a symmetric equilibrium without migration and an asymmetric equilibrium in which net income levels differ among jurisdictions and trigger migration flows. In the former equilibrium, all jurisdictions have the same public investment level. In the latter one, public investment is high in host economies of skilled expatriates and low in source economies. We empirically test the hypothesis that emigration rates are negatively associated with publicly financed investment levels for OECD countries.