Hypercongestion in production correspondences: an empirical exploration

This empirical contribution reviews the rather limited existing literature measuring congestion in production. It first compares current ways to measure congestion using nonparametric specifications of technologies. In particular, it focuses on the magnitude and incidence of the congestion detected in empirical studies using traditional radial efficiency measures. Thereafter, it shows the limitations of this radial measurement and how alternative measurement schemes may reveal higher amounts of congestion. Then, the new, more general methodology of measuring S-congestion is presented. In particular, we first present a numerical example to illustrate the way the S-disposable technologies allow to capture more extreme forms of congestion by setting empirically determined upper bounds to the wasting of inputs. Then, an empirical illustration is presented based on an existing sample of data. A final section concludes.     

Axioms for minimax regret choice correspondences

This paper unifies and extends the recent axiomatic literature on minimax regret. It compares several models of minimax regret, shows how to characterize the according choice correspondences in a unified setting, extends one of them to choice from convex (through randomization) sets, and connects them by defining a behavioral notion of perceived ambiguity. Substantively, a main idea is to behaviorally identify ambiguity with failures of independence of irrelevant alternatives. Regarding proof technique, the core contribution is to uncover a dualism between choice correspondences and preferences in an environment where this dualism is not obvious. This insight can be used to generate results by importing findings from the existing literature on preference orderings.     

Strong Equilibrium in Congestion Games

[6]introduced the class of congestion games and proved that they always possess a Nash equilibrium in pure strategies. Here we obtain conditions for the existence of a strong equilibrium in this class of games, as well as for the equivalence of Nash and strong equilibria. We also give conditions for uniqueness and for Pareto optimality of the Nash equilibrium. Except for a natural monotonicity assumption on the utilities, the conditions are expressed only in terms of the underlying congestion game form. It turns out that avoiding a certain type of bad configuration in the strategy spaces is essential to positive results.Journal of Economic LiteratureClassification Numbers: C71, C72, D62.     

Congestion management in power systems

In liberalized power systems, generation and transmission services are unbundled, but remain tightly interlinked. Congestion management in the transmission network is of crucial importance for the efficiency of these inter-linkages. Different regulatory designs have been suggested, analyzed and followed, such as uniform zonal pricing with redispatch or nodal pricing. However, the literature has either focused on the short-term efficiency of congestion management or specific issues of timing investments. In contrast, this paper presents a generalized and flexible economic modeling framework based on a decomposed inter-temporal equilibrium model including generation, transmission, as well as their inter-linkages. The model covers short-run operation and long-run investments and hence, allows to analyze short and long-term efficiency of different congestion management designs that vary with respect to the definition of market areas, the regulation and organization of TSOs, the way of managing congestion besides grid expansion, and the type of cross-border capacity allocation. We are able to identify and isolate implicit frictions and sources of inefficiencies in the different regulatory designs, and to provide a comparative analysis including a benchmark against a first-best welfare-optimal result. To demonstrate the applicability of our framework, we calibrate and numerically solve our model for a detailed representation of the Central Western European (CWE) region, consisting of 70 nodes and 174 power lines. Analyzing six different congestion management designs until 2030, we show that compared to the first-best benchmark, i.e., nodal pricing, inefficiencies of up to 4.6% arise. Inefficiencies are mainly driven by the approach of determining cross-border capacities as well as the coordination of transmission system operators’ activities.     

Theorems on correspondences and stability of the core

In this note two theorems strengthening Grodal's (1971) Theorem on correspondences are proved. The first drops the convexity assumption. The second strengthens that theorem further for the case when the range is the positive orthant. In this case, the conclusion of Grodal's Theorem - the intersection of the integral with the interior of the range being open- is modified to read as the integral being a relative open subset of the positive orthant. An example is provided to show that, such a strengthening is not valid in general. This allows us to dispense with the requirment of convexity of preferences in Grodal's (1971) theorems on the closedness of the set of Pareto optimal allocations, the core, and the continuity of the core correspondence for pure exchange economies. We apply this result to show that blocking coalitions in a large economy are stable. Received: September 30, 1998; revised version: September 18, 2001 RID="*" ID="*" The author is grateful to an anonymous referee for helpful comments. The usual disclaimer applies.     

Domestic and international economic changes. Embarrassing correspondences

The breakdown of the socialist regimes of the east European countries has been incredibly fast. The subsequent changes in the international setting may imply much slower processes. Unified Germany is building up a vast area of influence ranging from the Baltic to the Adriatic sea. The former Moslem republics of the Soviet Union may fall instead under the influence of Turkey, supported by the USA. The presence of the USA in the Middle East and the American influence over Israel, Saudi Arabia, and possibly Iran, might help to build up a huge Moslem area controlled by the USA. This implies questioning the pre-existing national borderlines, a problem in which ethnic conflicts seem to be playing a role. The three great economic areas of the world exhibit a common tendency to become three strongly protected commercial areas. In the domestic structures of the main capitalist countries very similar changes are taking place: a general fall in the ideals of social justice, replaced by the ideology of individual effort and efficiency; a decline in the belief that any individual should be protected from the cradle to the grave, a belief replaced by the ideal of a scoiety made up of self-made men; a decline in the supply of schooling services, health care, old-age pensions and collective action in general, in favour of individual initiative and privatization. A consequence of such changes will be a sharp increase in personal and regional inequalities.     

从博弈论的角度分析交通拥堵和拥堵收费问题

本文从博弈论角度考察了交通拥堵的微观经济学问题,并从出行者的出发时间决策入手,通过建立简单的两人拥堵博弈模型,分析了参与者在互动行为影响下,由自己和他人的行动共同决定的得益情况,并进一步将模型应用到拥堵收费定价研究中.     

伦敦交通拥挤的代价

本文通过描述伦敦交通拥挤收费制的起源以及现实中如何克服理论和实践层面的两难实施过程,对道路收费所引致的各种效应进行了论证.作者认为伦敦交通拥挤收费制的引入,应该归功于经济学的贡献,道路定价行动在克服交通拥挤的外部性上,不过是一种应对公众和政治利益诉求的适宜性政策回应.     

Congestion with heterogeneous commuters

We study a congestion model where a continuum of heterogeneous commuters make a binary choice between riding a bus and driving private vehicles for their commutes. Formulating the model as a large game, we establish the existence and uniqueness of a nontrivial Nash equilibrium and analyze how a gasoline tax affects the allocation of commuters between public transportation and private vehicles at the equilibrium. Based on the analysis, we provide a sufficient condition under which a gasoline tax is Pareto improving. We also prove the existence of a socially optimal policy that minimizes the aggregate loss to all commuters.     

Congestion games with malicious players

We study the equilibria of non-atomic congestion games in which there are two types of players: rational players, who seek to minimize their own delay, and malicious players, who seek to maximize the average delay experienced by the rational players. We study the existence of pure and mixed Nash equilibria for these games, and we seek to quantify the impact of the malicious players on the equilibrium. One counterintuitive phenomenon which we demonstrate is the “windfall of malice”: paradoxically, when a myopically malicious player gains control of a fraction of the flow, the new equilibrium may be more favorable for the remaining rational players than the previous equilibrium.     

On the continuity of equilibrium and core correspondences in economies with differential information

Summary. We study upper semi-continuity of the private and coarse core and the Walrasian expectations equilibrium correspondences for economies with differential information, with Boylan (1971) topology on agents information fields.Received: 16 January 2004, Revised: 28 October 2004, JEL Classification Numbers: D50, D82, C70. Correspondence to: Ezra EinyWe wish to thank Carlos Herves, Nicholas Yannelis, and an anonymous referee for their helpful comments.     

Congestion Pricing and Learning in Traffic Network Games

A stochastic model describing the learning process and adaptive behavior of finitely many users in a congested traffic network with parallel links is used to prove convergence almost surely toward an efficient equilibrium for a related game. To prove this result, we assume that the social planner charges on every route the marginal cost pricing without knowing what is the efficient equilibrium. The result is a dynamic version of Pigou’s solution, where the implementation is made in a decentralized way and the information about players gathered by the social planner is minimal. Our result and setting may be extended to the general case of negative externalities.     

Congestion and tax competition in a parallel network

The purpose of this paper is to study the effects of tolling road use on a parallel road network where each link can be tolled by a different government. Using both theoretical and numerical models, the paper analyses the potential tax competition between countries that each maximise the surplus of local users plus tax revenues in controlling local and transit transport. Three types of tolling systems are considered: (i) toll discrimination between local traffic and transit, (ii) only uniform tolls on local and transit transport are acceptable, (iii) tolls on local users only. The results suggest that the welfare effects of introducing transit tolls are large, but that differentiation of tolls between local and transit transport as compared to uniform tolls does not yield large welfare differences. Also, the welfare effects of toll cooperation between countries are relatively small in comparison with the welfare gains of non-cooperative tolling of transit. The numerical model further illustrates the effects of different transit shares and explicitly considers the role of asymmetries between countries. Higher transit shares strongly raise the transit toll and slightly decrease local tolls. With asymmetric demands, the welfare gains of introducing differentiated tolling rise strongly for the country with lower local demand.     

On the continuity of correspondences on sets of measures with restricted marginals

Summary. Consider the set of probability measures on a product space with the property that all have the same marginal distributions on the coordinate spaces. This set may be viewed as a correspondence, when the marginal distributions are varied. Here, it is shown that this correspondence is continuous. Numerous problems in economics involve optimization over a space of measures where one or more marginal distributions is given. Thus, for this class of problem, Berge's theorem of the maximum is applicable: the set of optimizers is upper-hemicontinuous and the value of the optimal solution varies with the parameters (marginals) continuously. Received: April 23, 1997; revised version: January 16, 1998     

Stable Assignment of Public Facilities under Congestion

We study the problem of locating multiple public facilities when each member of society has to be assigned to exactly one of these facilities. Individuals' preferences are assumed to be single‐peaked over the interval of possible locations and negatively affected by congestion. We characterize strategy‐proof, efficient, and stable allocation rules when agents have to be partitioned between two groups of users and discuss the normative content of the stability property. Finally we prove that when more than two groups have to be formed, even with common information on the distribution of the peaks, there is no strategy‐proof, efficient, and stable allocation rule.     

北京交通拥堵引起的生态经济价值损失评估

交通拥堵带来出行时间延误、额外燃料消耗、生态环境损害以及额外交通事故等诸多外部成本,国内外一些研究机构开发了估算交通拥堵外部成本的模型并取得了一定的研究结果,但仅限于对时间成本和燃料消耗成本的估算.借鉴以往的研究成果,构建了更全面的外部成本估算模型,并估算了2010年北京车辆因拥堵而导致的外部成本损失,以期为应治理城市交通拥堵、在城市积极推进节能减排工作提供参考依据.     

A characterization of social choice correspondences that implement the core of simple games

In a coalitional voting game, an alternative is said to be in the core when no majority is willing to replace it with another alternative. A social choice correspondence is a mapping which associates any profile of voters’ preferences with a non-empty subset of the set of alternatives, which is understood as the set of selected outcomes. We characterize the social choice correspondences which always select the core of a simple game for any profile of preferences. This work was completed when B. Tchantcho was Visiting assistant Professor at UTA (University of Texas at Arlington). We acknowledge the support of the Department of Mathematics of UTA. We are most grateful to R. Pongou of Brown University, USA for his help and advice. We sincerely thank N.G Andjiga for his helpful comments and we are indebted to two anonymous referees for their helpful comments.