A continuity property for local price adjustment mechanisms

This paper makes a case that a (local) continuity property is a reasonable one for any local price adjustment mechanism. This property means that if the starting points (i.e., initial prices) of the adjustment process are ‘close' to one another, and if the characteristics of the economies are ‘close' to one another, then, given any price adjustment mechanism, agents should compute equilibria that are ‘close' to one another. Under preferences which satisfy a ‘surjectivity hypothesis', it is shown that the tâtonnement process satisfies this continuity property on a nice subset of the space of all economies. A characterization of these economies for which the tâtonnement process is locally stable is given. Chart logic is a useful way to think about the path dependent property of implied volatility and about the relationship between implied volatility and historical volatility.     

Convergence of Bayesian learning to general equilibrium in mis-specified models

A central unanswered question in economic theory is that of price formation in disequilibrium. This paper lays the groundwork for a model that has been suggested as an answer to this question in, particularly, Arrow [Toward a theory of price adjustment, in: M. Abramovitz, et al. (Ed.), The Allocation of Economic Resources, Stanford University Press, Stanford, 1959], Fisher [Disequilibrium Foundations of Equilibrium Economics, Cambridge University Press, Cambridge, 1983] and Hahn [Information dynamics and equilibrium, in: F. Hahn (Ed.), The Economics of Missing Markets, Information, and Games, Clarendon Press, Oxford, 1989]. We consider sellers that monopolistically compete in prices but have incomplete information about the structure of the market they face. They each entertain a simple demand conjecture in which sales are perceived to depend on the own price only, and set prices to maximize expected profits. Prior beliefs on the parameters of conjectured demand are updated into posterior beliefs upon each observation of sales at proposed prices, using Bayes’ rule. The rational learning process, thus, constructed drives the price dynamics of the model. Its properties are analysed. Moreover, a sufficient condition is provided, relating objectively possible events and subjective beliefs, under which the price process is globally stable on a conjectural equilibrium for almost all objectively possible developments of history.     

Smooth preferences and the regularity of equilibria

To study equilibria we describe an economy by its distribution of consumers' preferences and endowments. All preferences are smooth and weakly convex. Demand of an economy need not be single valued, but there is an open dense set of economies for which demand is a C¹-function in a neighborhood of the equilibrium prices. We call an economy regular if its excess demand is transversal to zero. A regular economy has locally unique equilibria. It is shown that regular economies form an open dense set on which the equilibrium price correspondence varies continuously and the number of equilibria is locally constant.     

Further remarks on the Global Newton method

In this work, we are concerned with the behavior of Smale's ‘Global Newton’ process, starting from points not necessarily on the boundary. We find that the process is locally system stable in the sense that, sufficiently near an equilibrium, one is almost always led to some equilibrium of the system. However, the ‘Global Newton’ process is found typically not to be globally stable; instead, families of cycles appear, preventing convergence to equilibrium.     

Asset price and wealth dynamics in a financial market with heterogeneous agents

This paper considers a discrete-time model of a financial market with one risky asset and one risk-free asset, where the asset price and wealth dynamics are determined by the interaction of two groups of agents, fundamentalists and chartists. In each period each group allocates its wealth between the risky asset and the safe asset according to myopic expected utility maximization, but the two groups have heterogeneous beliefs about the price change over the next period: the chartists are trend extrapolators, while the fundamentalists expect that the price will return to the fundamental. We assume that investors’ optimal demand for the risky asset depends on wealth, as a result of CRRA utility. A market maker is assumed to adjust the market price at the end of each trading period, based on excess demand and on changes of the underlying reference price. The model results in a nonlinear discrete-time dynamical system, with growing price and wealth processes, but it is reduced to a stationary system in terms of asset returns and wealth shares of the two groups. It is shown that the long-run market dynamics are highly dependent on the parameters which characterize agents’ behaviour as well as on the initial condition. Moreover, for wide ranges of the parameters a (locally) stable fundamental steady state coexists with a stable ‘non-fundamental’ steady state, or with a stable closed orbit, where only chartists survive in the long run: such cases require the numerical and graphical investigation of the basins of attraction. Other dynamic scenarios include periodic orbits and more complex attractors, where in general both types of agents survive in the long run, with time-varying wealth fractions.     

Why a simple herding model may generate the stylized facts of daily returns: explanation and estimation

The paper proposes an elementary agent-based asset pricing model that, invoking the two trader types of fundamentalists and chartists, comprises four features: (i) price determination by excess demand; (ii) a herding mechanism that gives rise to a macroscopic adjustment equation for the market fractions of the two groups; (iii) a rush towards fundamentalism when the price misalignment becomes too large; and (iv) a stronger noise component in the demand per chartist trader than in the demand per fundamentalist trader, which implies a structural stochastic volatility in the returns. Combining analytical and numerical methods, the interaction between these elements is studied in the phase plane of the price and a majority index. In addition, the model is estimated by the method of simulated moments, where the choice of the moments reflects the basic stylized facts of the daily returns of a stock market index. A (parametric) bootstrap procedure serves to set up an econometric test to evaluate the model’s goodness-of-fit, which proves to be highly satisfactory. The bootstrap also makes sure that the estimated structural parameters are well identified.     

On the existence,uniqueness and stability of spatial equilibrium in an open city with externalities

This paper deals with the existence, uniqueness and stability of a spatial equilibrium in an open city with external diseconomies like air pollution generated by manufacturing activities. First, assuming that both production functions and utility functions are Cobb-Douglas, we prove the existence of a spatial equilibrium under some reasonable assumptions. It is shown, however, that the uniqueness and stability of the equilibrium may not be obtained, unless the degree of externality is sufficiently small. In fact, none of the equilibria will be stable for a certain set of speeds of adjustment in the labor market and the land market, if the degree of externality is relatively large. Finally, some implications of our results are derived in regard to the application of the hedonic price concept within the context of a spatial equilibrium model.     

Sluggish quantity adjustment in a non-clearing market—a disequilibrium econometric application to the loan market

The paper argues that the estimated speed of price adjustment in a disequilibrium econometric model is likely to be biased if allowance is not made for quantity adjustment inertia on both sides of the market. Furthermore, if the model estimated is static rather than dynamic then, in certain circumstances, an excess demand regime may be mistaken for one of excess supply and vice-versa. In an empirical application to the loan market for the clearing banks in Ireland we can claim to have obtained some support for this belief.     

A Theoretical Analysis of Liner Shipping Conferences and Strategic Alliances

We analyze the economic impacts of industrial organizational struggles on the international liner shipping market. Operating ratios of different markets are discussed by incorporating rate, service level, and other variables into a standard microeconomic model. If two different carriers agree on a shipping conference price and/or share a strategic alliance service level, and maximize consolidated profit, a member carrier finds it easier to make its operation profitable than the individual profit optimization case; other carriers are worse off in becoming profitable. If the carriers face inelastic demand, the price continues rising until demand becomes elastic enough for the equilibrium to be relevant. The conference is expected to play a coordination role so that the market does not become unsustainable in the adjustment process to reach equilibrium.     

Perturbed utility and general equilibrium analysis

We study general equilibrium theory of complete markets in an otherwise standard economy with each household having an additive perturbed utility function. Since this function represents a type of stochastic choice theory, the equilibrium of the corresponding economy is defined to be a price vector that makes its mean expected demand equal its mean endowment. We begin with a study of the economic meaning of this notion, by showing that at any given price vector, there always exists an economy with deterministic utilities whose mean demand is just the mean expected demand of our economy with additive perturbed utilities. We then show the existence of equilibrium, its Pareto inefficiency, and the upper hemi-continuity of the equilibrium set correspondence. Specializing to the case of regular economies, we finally demonstrate that almost every economy is regular and the equilibrium set correspondence in this regular case is continuous and locally constant.     

Minimaximin results with applications to economic equilibrium

Abstract theorems are proved that can be used to establish the existence of a free disposal equilibrium in some infinite dimensional models of the economy. The results generalize those previously proved in that they apply to concave–convex functions rather than bilinear functions and excess demand correspondence dedicated to Professor Heinz König rather than excess demand functions.     

一类价格调整问题的数学模型及其求解方法

虽然市场需求是价格的函数，但企业在价格调整实践中往往不能直接获取需求函数的具体表达式，而只能在某一给定价格水平下观察到市场需求量的值。因此，企业通常不能直接利用需求函数来调整价格以完成预期的市场需求调整的战略计划。本文将企业为达到市场需求战略调整目的而考虑的价格调整问题归结为一个隐式互补问题。在该模型中，企业可以依据自身经营战略目标的调整相应地调整各类产品的市场价格，使得价格调整后的产品销量迭到预定的目标。文章给出了求解这类隐式互补问题的直接迭代法，并给出了数值结果。     

城镇专业市场形成的供需机制分析

在分析本地专业市场的地理意义及其对供需的空间聚集能力的基础上,由生产带动和消费带动两种模式入手对本地专业市场的供需互动形成机制进行探讨.通过分析行业平均价格指导下的供需曲线变化,寻求对本地专业市场形成机制的解答,并以国内相关城镇的专业市场实例进行印证,得出在不同模式下本地专业市场的形成条件.结论显示,城镇专业市场是在本地与外地的供给与需求互动过程中有条件地形成的.     

房地产市场调控，要坚持更要完善——“十年调控”问卷调查的启示和思考

通过对196份问卷的总结分析，得到对于未来房地产调控的许多启示：十年房地产调控是必要的；总体评价消极的依据是供求依然失衡，房价越来越高。调控成效不彰的原因有：对住房供求政策、调控配套政策评价消极，还认为财政税收压力是地方政府不积极的首要原因。大多数问卷建议：推动供求和房价基本稳定还是调控首要目的确立；房价合理上升的几个界限；房地产调节机制应该以市场调节为主、政府调节为辅；明确住房需求政策、住房供给政策、住房土地政策、经济手段、行政手段和税收手段改进的方向。     

Residential energy demand in the United States: A regional econometric analysis

A static equilibrium and a dynamic partial adjustment model of residential demand for electricity and natural gas are presented and estimated for the United States over a recent period characterized by sharply increasing energy prices. The static model is estimated using Ordinary Least Squares while the instrumental variables method is used for the dynamic partial adjustment model. The estimates of long-run elasticities suggest the residential demand for electricity and natural gas are price and income elastic. Intercept and slope dummies used in the models identify significant regional differences in demand functions.     

Output-inflation cycles in an economy with staggered wage setting

The question whether increased price flexibility is stabilizing in macromodels of the business cycle has been recently questioned by De Long and Summers (1986). The present paper is an attempt to reconsider the question by applying some methods from the theory of nonlinear dynamics, especially bifurcation theory, to the analysis of a dynamic model with sluggish price adjustment. It is argued that, when inflation plays a destabilizing role through the Mundell effect, a stable closed orbit representing the perfect-foresight dynamics of the output-inflation pair may appear in the vicinity of a stationary state. Moreover, bifurcation theory is applied to find analytical results about the relation between the amplitude of the cycles and the ‘degree’ of flexibility of prices. This relation is shown to be positive in a variety of cases.     

Unemployment,disequilibrium and the short run phillips curve: An econometric approach

The paper specifies a disequilibrium model for the aggregate labour market consisting of demand and supply functions for labour, an adjustment equation for wages as well as for prices, a transactions equation and, finally, an equation that relates measured unemployment to vacancies and to excess demand. The model has a more sophisticated treatment of dynamics than earlier disequilibrium models. The parameter estimates and the goodness-of-fit are satisfactory and the model's implications for the behaviour of several important variables are sensible. In particular, excess demand estimates computed in various ways are reasonable.     

The economics of retail firms

This paper identifies retail firms as an economic institution which delivers explicit products or services to consumer together with a variety of distribution services that determine the levels of distribution costs experienced by consumers in their purchase activities. The demand for the retailer's product is derived from a household production model in which the levels of distribution services provided by the retailer play the role of fixed inputs in the household's production functions. The supply of the retailer's product is derived from a joint cost function which is non-decreasing in the levels of distribution services provided. Profit-maximizing behavior in monopolistically competive markets shows that retail firms have special economic incentives to become complex organizations by integrating backwards, offering multiple explicit products and operating in more than one market. In addition, monopolistically competitive retail firms in long-run equilibrium will exhibit excess capacity, price dispersion and product choice in distribution services.     

On pure-strategy Nash equilibria in price–quantity games

This paper examines the existence and characteristics of pure-strategy Nash equilibria in oligopoly models in which firms simultaneously set prices and quantities. Existence of a pure-strategy equilibrium is proved for a class of price–quantity games. If the demand function is continuous, then the equilibrium outcome is similar to that of a price-only model. With discontinuous demand and limited spillover, there are rationing equilibria in which combined production falls short of market demand. Moreover, there might again be an equilibrium reflecting the outcome of a price game. Competition in price and quantity thus yields Bertrand outcomes under a variety of market conditions.     

CHINESE EXPERIENCE IN THE INTRODUCTION OF A MARKET MECHANISM INTO A PLANNED ECONOMY: THE ROLE OF PRICING

Abstract. A brief review is first presented of the changes in pricing institutions in China since 1949, with particular emphasis on the shift from an equilibrium price system to a distorted price system. The authors argue that distorted prices are harmful to economic growth even in a planned economy, since even an experienced economic planner can never escape from the full implications of a distorted price system. Examples are given showing the detrimental results of such a system. The central point of China's economic reform is the extension of decision-making power to enterprises and the introduction of a market mechanism so as to improve microeconomic efficiency. But such a goal cannot easily be achieved due to the false information provided by the distorted price system. So price adjustment becomes an issue of primary importance, and the authors discuss the difficulties for price adjustment posed by various interest groups.