Symmetry and continuity properties of Lindahl equilibria

In this paper it is shown that: (1) some non-symmetric Lindahl equilibria may exist; (2) under usual assumptions, the set of symmetric Lindahl equilibria is non-empty; (3) however, the correspondence which associates with every economy the set of symmetric Lindahl equilibria is not a closed correspondence; (4) there are economies with a measure space of economic agents in which every Lindahl equilibrium is discontinuous.     

Equilibrium Exchange Rates in Transition Economies: Taking Stock of the Issues*

Abstract. In this paper, we present an overview of a number of issues relating to the equilibrium exchange rates of transition economies of the former soviet bloc. In particular, we present a critical overview of the various methods available for calculating equilibrium exchange rates and discuss how useful they are likely to be for the transition economies. Amongst our findings is the result that the trend appreciation usually observed for the exchange rates of these economies is affected by factors other than the usual Balassa–Samuelson effect, such as the behaviour of the real exchange rate of the open sector and regulated prices. We then consider three main sources of uncertainty relating to the implementation of an equilibrium exchange rate model, namely: differences in the theoretical underpinnings, differences in the econometric estimation techniques, and differences relating to the time‐series and cross‐sectional dimensions of the data. The ensuing three‐dimensional space of real misalignments is probably a useful tool in determining the direction of a possible misalignment rather than its precise size.     

Two definitions of correlated equilibrium

Correlated equilibrium constitutes one of the basic solution concepts for static games with complete information. Actually two variants of correlated equilibrium are in circulation and have been used interchangeably in the literature. Besides the original notion due to Aumann (1974), there exists a simplified definition typically called canonical correlated equilibrium or correlated equilibrium distribution. It is known that the original and the canonical version of correlated equilibrium are equivalent from an ex-ante perspective. However, we show that they are actually distinct – both doxastically as well as behaviourally – from an interim perspective. An elucidation of this difference emerges in the reasoning realm: while Aumann’s correlated equilibrium can be epistemically characterized by common belief in rationality and a common prior, canonical correlated equilibrium additionally requires the condition of one-theory-per-choice. Consequently, the application of correlated equilibrium requires a careful choice of the appropriate variant.     

On the robustness of the competitive equilibrium: Utility-improvements and equilibrium points

We show that the set of competitive equilibrium points of a pure exchange economy are the equilibrium points of a broader class of better-response demands than the usual utility-maximizing demand functions. The better-response demands are derived from assigning weights to all commodity bundles with higher utility than the current commodity bundle, with the greatest weights being placed on the commodity bundles with the highest utility gain. The usual utility-maximizing demand functions are then those in which the weight on the utility-maximizing bundle is one. We also show that these better-response demands belong to a large class of response maps that are generated by monotonic transformations of the utility functions and/or monotonic transformations of the weights assigned to the commodity bundles.     

Trading constraints penalizing default: A recursive approach

This paper proves existence of an ergodic Markov equilibrium for a class of general equilibrium economies with infinite horizon, incomplete markets, and default. Agents may choose to deny their liabilities and face trading constraints that depend on the adjusted amount of past default on each asset. These constraints replace the usual utility penalties and explore intertemporal tie-ins that appear in dynamic economies. The equilibrium prices and solvency rates present stationary properties that are usually required in econometric models of credit risk.     

Rational expectations and the econometric modeling of markets subject to uncertainty: A Bayesian approach

Rational expectations theory is synthesized with Bayesian econometric theory to yield econometrically relevant models of competitive markets subject to uncertainty. The theory is used to derive both optimal estimators of the parameters of a Cobb-Douglas production function from time series data, and the equilibrium predictor of a future price. It is shown that a rational expectations price predictor is always an unbiased predictor, but that the converse is not true. It is also shown that the rational expectations equilibrium is a natural extension of the usual notion of a competitive equilibrium.     

基于资源理论的虚拟企业均衡性研究

从资源理论的角度,对虚拟企业的形成进行了简单推理,界定了虚拟企业的性质;在此基础上,探讨了基于资源的理论的虚拟企业均衡的实现过程,分析了均衡实现的不同路径,最后提出了虚拟企业的一般战略均衡。     

Discrete-space agglomeration model with social interactions: Multiplicity,stability, and continuous limit of equilibria

This study examines the properties of equilibrium, including the stability, of discrete-space agglomeration models with social interactions. The findings reveal that while the corresponding continuous-space model has a unique equilibrium, the equilibrium in discrete space can be non-unique for any finite degree of discretization by characterizing the discrete-space model as a potential game. Furthermore, it indicates that despite the above result, any sequence of discrete-space models’ equilibria converges to the continuous-space model’s unique equilibrium as the discretization of space is refined.     

Existence of equilibrium configurations of competitive firms on an infinite two-dimensional space

This paper analytically examines the existence of equilibrium configurations of competitive firms on an infinite two-dimensional space. It is shown that the Löschian configuration (a regular-hexagonal lattice) and a square lattice are in global equilibrium; the Löschian configuration is in the strongest global equilibrium among the regular lattices (in this sense, spatial competition leads to the social optimum); and the so-called back-to-back configuration is not in equilibrium. These results are in marked contrast to those obtained from a one-dimensional model, implying that spatial equilibrium configurations in a two-dimensional space should not be inferred only from one-dimensional models frequently employed in spatial economics.     

Trading in exhaustible resources in the presence of conversion costs a general equilibrium approach

We survey the literature on the general equilibrium approach to trade in exhaustible resources and present a model in which conversion costs are incorporated and in which the usual balance of payments condition is relaxed. It is found that in many cases the problem of dynamic inconsistency will arise.     

Chamberlinian Spatial Computable General Equilibrium Modelling: A Theoretical Framework

In this paper, a multi-regional multi-sectoral computable general equilibrium model is developed by bringing together different strands of theoretical reasoning. These are as follows: input–output analysis, gravity modelling, the theory of intra-industry trade and the theory of general equilibrium under conditions of monopolistic competition. The innovation in this approach is the assumption that, within each sector, a large number of different brands of output are produced. Households like diversity of consumption and diversity of inputs is a productive factor for firms. The number of brands produced in each sector and region is endogenous. A certain amount of fixed costs per brand imposes an upper bound on the number of available brands. Factor markets are perfectly competitive, while monopolistic competition prevails on goods markets. The equilibrium solution of the model closely resembles models which have been applied on an ad hoc basis in regional science before, but it is well founded in modern economic theory now. In particular, trade flows obey a gravity law in equilibrium.     

Technical skill bias as a response of firms to unemployment: A matching model with applicant ranking and endogenous skill requirements

This paper considers an economy with heterogeneous workers where identical firms optimally decide on the degree of complexity of jobs. Meetings are depicted by an urn-ball process where firms rank their applicants and pick the best one. We show that a general rise in unemployment induces an increase in the employment shares of high-skilled workers which, in turn, makes firms choose more complex jobs, leading then to a decrease in the output of low-skilled workers. The technical skill bias is therefore related to the usual explanations of unemployment. Next, we state that a decentralized equilibrium is efficient in terms of job complexity but inefficient in terms of job creation when firms internalize the usual congestion effect. We then extend the analysis to a dynamic model.     

Generic properties of the core and equilibria of pure exchange economies

We show that for an open dense set of markets with a continuum of traders the number of equilibrium allocations [which by the celebrated theorem of ^{Aumann (Econometrica. 1964, 32. 39–50)} coincide with the core allocations for such markets are finite. This presents a limiting case result that complements similar asymptotic theorems for cores of large economies proved by ^{Bewley (Econometrica 1973, 41, 425–454)}, and ^{Dierker (Journal of Mathematical Economics 1975, 2. 155–169)}. If we require that the measure on the space of agents be one with a finite number of atoms of equal weight, our reasoning recovers the classical results obtained by ^{Debreu (Econometrica. 1970. 38, 387–392)} for economies with a finite number of agents.     

General competetive equilibrium of the spatial economy

The spatial economy is analyzed in the general equilibrium framework by considering the production and the utility functions depending on spatial distribution and sets. The geometric constraint between the location and the extension of goods supplies the equilibrium condition for space. The existence of an equilibrium is demonstrated by extending the Gale-Nikaido theorem to the case under examination. Consequently, the competetive equilibrium exists, under the assumptions of the theorem, although each point of space is heterogeneous with any other point (because of the different location): the existence is allowed by the perfect partibility of space.     

A conditional minimax approach in survey sampling

Summary Applying the usual minimax criterion in finite sampling theory yields complicated solutions except the parameter space has certain invariance properties. A conditional minimax criterion is suggested. After a sample is selected it is reasonable to seek an estimator that has good properties (e.g. minimaxity) for that sample. Explicit solutions are given in the case where the parameter space is described by quadratic forms.     

Can harmful events be another source of environmental traps?

This paper aims to present a new explanation for environmental traps through the presence of endogenous hazard rate. We show that adaptation and mitigation policies affect the occurrence of environmental traps differently. The former could cause environmental traps, whereas the latter could help society avoid such traps by decreasing the probability of a harmful event occurring. As a result, we present a new trade-off between adaptation and mitigation policies different than the usual dynamic trade-off that is highlighted in many studies and is crucial to developing countries. Contrary to the literature, when an economy is in a trap, an economy with a high environmental quality equilibrium tends to be more conservative in terms of resource exploitation than an economy with a low environmental quality equilibrium, which implies a heterogeneous reaction against the endogenous hazard rate.     

Preservation of Open Space and the Concept of Value*

Abstract . This paper identifies and classifies six major kinds of values which people ascribe to areas of open space (utility, functional, contemplative, aesthetic, recreational, and ecological values), whether the open space is public or private, urban or rural, or large or small. These values are predominantly culturally-shaped attitudes. They are not mutually exclusive but nonetheless cannot be subsumed under just one notion of value such as trade-offs and, consequently, models for evaluating open space based on the familiar utility function are inadequate representations of human reasoning. Public policy concerned with preserving open space must incorporate a multidimensional set of noncommensurate values and one paradigm for doing so is discussed.     

Competitive equilibria in general choice spaces

This paper primarily demonstrates the existence of Arrow-Debreu equilibria in a general class of topological vector spaces of commodity bundles. Two conditions based on production possibilities, preferences, and the topological nature of bounded sets are shown to substitute, in any locally convex space, for the advantages of the Euclidean topology. Examples fulfilling these conditions are supplied. The approach is that of Bewley, demonstrating equilibria on finite dimensional sub-economies and establishing a net of these equilibria that converges to an equilibrium on the whole commodity space. An example of equilibrium with a storage technology is given. An auxiliary result concerns the price support of efficient allocations.     

The Aubin private core of differential information economies

Abstract We establish characterizations of Radner equilibrium allocations via private core notions in the framework of differential information economies with a finite number of states of nature and a measure space of agents that may have atoms. The commodity space is an ordered separable Banach space whose positive cone admits an interior point. We introduce the notion of Aubin private core and prove that it provides a characterization of Radner equilibrium allocations. We show that the Aubin private core is equivalent to Edgeworth private equilibria and to privately non-dominated allocations of suitable associated economies. Mathematics Subject Classification (2000): 91B50, 91B44 Journal of Economic Literature Classification: D51, D82, D11