Liberalisation,competition and ownership in the presence of vertical relations

This contribution analyses a market with an upstream bottleneck monopoly and a downstream activity that may either be vertically integrated or separated. Separation always reduces the consumer surplus, and the total surplus unless there are large cost reductions. Downstream competition from a public or private network monopoly would crowd out other firms, also when public ownership is associated with more modest objectives than welfare-maximisation. A market is therefore less likely to remain a mixed oligopoly than without vertical relations. However, private firms would survive in a moderately welfare-improving mixed oligopoly with cross-subsidisation and access charges equal to marginal costs.

Equality of opportunity and optimal cash and in-kind policies

This paper examines the argument for public provision of certain private goods, like education and health, based on equality of opportunity by studying the utility possibility frontier of a society in which there is a concern for the distribution of these goods. A given quality of education or health services can be consumed for free in the public sector, but people can opt-out and purchase their desired quality levels in the private sector. Some of the conclusions are: (i) a pure cash transfer is optimal when the utility redistribution is either “sufficiently” small or large; (ii) if and only if both the equality-of-opportunity concern and the utility redistribution are large enough, can an in-kind program which attracts the whole population be justified; (iii) even when everybody chooses the in-kind program, it may be optimal to perform some additional utility redistribution by increasing the size of such program.     

How Communication Improves Efficiency in Bargaining Games

We study a double auction with two-sided private information and preplay communication, for which Myerson and Satterthwaite (1983, J. Econ. Theory28, 265–281) showed that all equilibria are inefficient and the Chatterjee–Samuleson linear equilibrium is most efficient. Like several others, we find that players use communication to surpass equilibrium levels of efficiency, especially when the communication is face-to-face. Our main contribution is an analysis of how communication helps the parties achieve such high levels of efficiency. We find that when preplay communication is allowed, efficiency above equilibrium levels is a result of what we call “dyadic” strategies that allow the parties to coordinate on a single price that reflects both parties' valuations. Journal of Economic Literature Classification Numbers: C78, D82.     

Tiebout equilibria in local public good economies with spillovers

This paper analyzes the effects of spillovers on the equilibrium population distribution across jurisdictions in a local public good economy with free mobility. Spillovers are parametrized by a matrix [α_ij] where α_ij ∈ [0, 1]. When spillovers are symmetric and close to 0 or 1 (pure local public goods and pure public goods), all equilibrium jurisdiction structures are symmetric. However, any population distribution can be sustained in equilibrium for some value of the spillover parameter α. In the class of utility functions with additive externalities, we identify the unique family of utility functions for which equilibria are symmetric except for an isolated value of α. This is a class of utility functions which are linear in the public good and a power function of the private good, u(c, γ) = − A(1 − c)^β + γ. With this specification of utility, we show that an increase in α results in a more fragmented equilibrium population distribution, and that when spillovers are asymmetric and large, a jurisdiction which is more centrally located (i.e. benefits more from the public goods provided in other jurisdictions) has a larger population in equilibrium.     

Symmetric Separating Equilibria in English Auctions

We characterize the set of perfect Bayesian equilibria in symmetric separating strategies in the model of English auctions given by P. R. Milgrom and R. J. Weber (1982, Econometrica50, 1089–1122). There is a continuum of such equilibria. The equilibrium derived by Milgrom and Weber is that in which bids are maximal. Only in the case of pure private values does a restriction to weakly undominated strategies select a unique equilibrium. This has important implications for empirical studies of English auctions, particularly outside the pure private values paradigm. Journal of Economic Literature Classification Numbers: D44, D82.     

The stability of the cournot oligopoly model: A reassessment

The stability properties of the Cournot oligopoly model are examined for the continuous adjustment process. Sufficient conditions for instability are established which are shown to be of significance when the number of firms, n, is small. Local and global stability are shown under appropriate conditions which for global stability include the restriction n ? 5. The proof of global stability corrects a well-known proof by F. Hahn (Rev. Econ. Stud.29 (1962), 329–331). Results for the discrete time adjustment process are reported and the restrictiveness of the model's assumptions are discussed.     

Competition in telecommunication networks with call externalities

This paper describes a model involving two interconnected networks offering different degrees of quality. In these networks, there are call externalities enabling consumers to assess the quality of the calls they send and receive. Networks compete in two-part tariffs. Our aim is to show that the “profit neutrality” result no longer applies due to network asymmetry and call externalities. In the case of non reciprocal access charges, call externalities generate private incentives enabling each competitor to charge low access prices. This reduces the risk of tacit collusion as competitors are free to negotiate their access charges.      

Measures of technical efficiency

Färe and Lovell (J. Econom. Theory19 (1978), 150–162) suggest four properties that a measure of technical efficiency should satisfy; the commonly employed Debreu-Farrell measure fails three of them. Necessary and sufficient conditions for a measure to satisfy the four conditions are provided and recently proposed measures are analyzed in the light of this result. Also, it is argued that the Debreu-Farrell measure has several desirable properties when one takes account of (1) (perhaps unknown) market prices and the relationship between technical and economic efficiency and (2) its characterization as a measure of economic efficiency using the shadow prices implicit in the production technology.     

Evolution of market shares with repeated purchases and heterogeneous network externalities

We investigate how market shares change when a new, superior technology exhibiting network externalities is introduced in a market initially dominated by an old technology. This is done under the assumption that consumers are heterogeneous in their valuation of technology quality and network externalities and that goods are not (perfectly) durable and thus have to be bought repeatedly. When both technologies are unsponsored, the old technology dominates when the quality difference is small, and it disappears when the quality difference is large. When the new technology is sponsored, the relationship between the quality difference and the long-run market share of the new technology is non-monotonic and the old technology always continues to exist.

Exact aggregation and Generalized Slutsky Conditions

This article indicates a natural connection between Generalized Slutsky Conditions and demand structures of the exact aggregation form. It is shown that Generalized Slutsky Conditions are assured when the number of consumers is greater than or equal to the number of goods, if and only if demands are of a generalized exact aggregation form. This result provides some understanding of the properties of aggregate demand and allowable differences between consumers, as well as naturally generalizing W. M. Gorman's (Econometrica21 (1953), 63–80) famous conditions for the integrability of aggregate demand.     

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).     

Should mobile capital pay for public infrastructure investment?

The paper contributes to the discussion of fiscal competition with infrastructure goods. We explicitly focus on the costs of providing public infrastructure capital that appear in the public budget as investment. Thus we analyse the problem in a dynamic framework. Public infrastructure is considered as a marginal product complement to private capital. A central result of the model is that the fact that public capital is a complement to private capital, so that an increase in the supply of public capital ceteris paribus improves the marginal productivity of private capital, cannot be used as an argument to support a source tax. The so-called indirect productivity effect on private capital induced by public inputs does not justify the taxation of mobile capital. Rather, the efficiency of a source tax on mobile capital income depends on the question of whether or not the public input generates a factor rent to private capital.

A Unifying Pair of Cournot-Nash Equilibrium Existence Results

For games with a measure space of players a tandem pair, consisting of a mixed and a pure Cournot-Nash equilibrium existence result, is presented. Their generality causes them to be completely mutually equivalent. This provides a unifying pair of Cournot-Nash existence results that goes considerably beyond the central result of E. J. Balder (1995, Int. J. Game Theory24, 79-94, Theorem 2.1). The versatility of this pair is demonstrated by the following new applications: (i) unification and generalization of the two equilibrium distribution existence results by K. P. Rath (1996, J. Math. Econ.26, 305-324) for anonymous games, (ii) generalization of the equilibrium existence result of T. Kim and N. C. Yannelis (1997, J. Econ. Theory77, 330-353) for Bayesian differential information games, (iii) inclusion of the Bayesian Nash equilibrium existence results of P. R. Milgrom and R. J. Weber (1985, Math. Oper. Res.10, 619-632) and E. J. Balder (1988, Math. Operations Res.13, 265-276) for games with private information in the sense of J. C. Harsanyi (1967, Manage. Sci.14, 159-182). Journal of Economic Literature Classification Number: C72.     

Proportional taxation: Nonexistence of stable structures in an economy with a public good

Guesnerie and Oddou [J. Econom. Theory25 (1981), 67–91] raised the open question whether an economy, in which the production of a public good is financed via proportional taxation, has a stable structure. By means of the first example a negative answer to this question is provided. The second example shows that a stable structure may fail to exist even if all the individuals have the same initial endowments in private good.     

Resource egalitarianism with a dash of efficiency

We study the problem of defining inequality-averse social orderings over allocations of commodities when individuals have different preferences. We formulate a notion of egalitarianism based on the axiom that any dominance between consumption bundles should be reduced. This Dominance Aversion requirement is compatible with Consensus, a version of the Pareto principle saying that an allocation y is better than x whenever everybody finds that everyone?s bundle at y is better than at x. We characterize a family of multidimensional leximin orderings satisfying Dominance Aversion and Consensus.     

Some regulatory lessons to be drawn from the financial crisis

The article briefly outlines how the two major structural causes of the financial crisis have been a massive underestimation of the negative externalities potentially arising from malfunctioning of financial markets, and the policy decision to assign the production of an eminently public good, financial stability, to private parties. Both ideas have been a tenet of the so-called Greenspan doctrine. The crisis also shows that all regulators tend to be captured in the end, and thus any new legislation should contain bright-line rules, that might look inefficient when assessed with reference to the market they regulate, but are socially efficient, because it would be politically costly to alter them. Criminal sanctions, which after all are a social form of regulation, should also be strengthened.

A Robust Folk Theorem for the Prisoner's Dilemma

We prove the folk theorem for the Prisoner's dilemma using strategies that are robust to private monitoring. From this follows a limit folk theorem: when players are patient and monitoring is sufficiently accurate, (but private and possibly independent) any feasible individually rational payoff can be obtained in sequential equilibrium. The strategies used can be implemented by finite (randomizing) automata. Journal of Economic Literature Classification Numbers: C72, C73, D82.     

An extension of Fishburn's theorem on extending orders

P. C. Fishburn [J. Econom. Theory31 (1983), 000-000] has shown that one can extend any well ordering of a set to a linear ordering of the set of all non-empty subsets of that set, while satisfying two axioms denoted (GP¹) and (M¹). By applying the compactness theorem of logic, this note shows that the well ordering assumption can be waived. Definability and well ordering properties of the extension are also discussed and shown to depend on the class of basic orderings considered.     

Zero-sum condition: A necessary and sufficient condition for a transitive voting system

A simple and quick way to ascertain whether or not any given majority voting system can always produce a transitive social preference orderings without imposing any restriction on the distribution of diverse individual preference orderings is to examine whether all individual voting (preference) vectors satisfy the Addition Rule or not. This conclusion was obtained by first reformulating the voting mechanism into that of a linear mapping from T^m defined by q = Σp_i. It was found that the subset P of T that can accommodate all possible individual preference ordering profiles and such that every sum vector q = Σ p_i of its member vectors p_i is contained in T can be expressed as P = {p: p∈ T, s(p) = 0}. It was also pointed out that this is equivalent to the requirement that all individual preference (voting) functions must satisfy the Addition Rule. Finally, Borda's Rule and Saposnik's Contributive Rule were shown to be examples of transitive voting rules which satisfy these necessary and sufficient conditions.     

Dynamic stability and reform of political institutions

This paper examines endogenous institutional change in a class of dynamic political games. The political aggregation rules used at date t+1 are instrumental choices under rules at date t. Effectively, rules are “players” who can strategically delegate future policy-making authority to different rules. A political rule is stable if it selects itself. A reform occurs when an alternative rule is selected. The stability of a political rule is shown to depend on whether its choices are dynamically consistent. For instance, simple majority rules can be shown to be dynamically consistent in many common environments where wealth-weighted voting rules are not. The result extends to political rules that incorporate private activities such as extra-legal protests, threats, or private investment. The approach is one way of understanding various explanations of institutional change proposed in the literature. A parametric model of public goods provision gives an illustration.