Efficient price and capacity choices under uncertain demand: An empirical analysis

Traditional economic analyses of the peak-load problem typically assume an unrealistic degree of regularity in demand during well-defined peak and off-peak periods. This issue is addressed through a comprehensive statistical model that separates demand into its systematic and stochastic components. This model is combined with a traditional economic model and applied to local telephone service, leading to substantive conclusions relevant for managerial decisions as well as further research, among them:

? Neglecting the systematicand stochastic structure of demand may lead to inefficient tariffs. Efficient measured service structures typically price individual callsbelow incremental capacity cost.

? Industry wide capacity decision rules that are exclusively driven by blockage probability targets during narrowly defined time periods may be economically inefficient.

? For telephone service, spot pricing, which sets high prices during periods ofactual congestion, has the potential to be considerably more efficient than traditional tariffs that set high prices during periods ofexpected congestion.

     

中国经济周期特征与财政政策效应——一个基于三部门RBC模型的实证分析

本文采用随机动态一般均衡方法,将政府支出作为外生随机冲击变量,构建中国三部门实际经济周期(RBC)模型,并对改革后的中国经济进行了实证检验,从而考察中国宏观经济波动的周期特征及财政政策的效应问题。研究发现,在包含政府部门的RBC模型中,技术冲击和政府支出冲击可以解释70%以上的中国经济波动特征,中国经济波动是技术因素、供给因素和需求因素综合影响的共同产物。此外,本文证实改革后政府支出对居民消费产生了一定的挤出效应。     

An economic theory of leadership turnover

In an infinite-horizon stochastic model, a coup not only disciplines a dictator's policy towards a group of “kingmakers”, but also enables a kingmaker to become a dictator. Greater competition for the dictator's position, a lower impact of the dictator's policy on the kingmakers, or lower risks of staging a coup raises the benefit of a coup relative to its opportunity cost and so raises the probability of a coup. Since periodic shocks affect the efficacy of the dictator's policy, a bad enough shock makes it too costly for even talented dictators to avert a coup. More talented dictators are able to survive more negative shocks, so the worst shock in a dictator's reign is informative about the probability of a coup. Conditional on the worst shock, the probability of a coup is independent of a dictator's duration in office. The unconditional probability declines with duration.     

Pricing power supplied on an interruptible basis

This paper deals with Pareto-optimal pricing of an electric utility whose demand is subject to random fluctuations. Its purpose is to extend previous results obtained by Boiteux and Drèze in two directions. First, the maximum power contracted by subscribers is charged instead of the variance of individual consumptions, which makes the model closer to most existing rate structures. Second, subscribers are allowed to choose among several types of supply differentiated by the probability with which their delivery is guaranteed. Most electricity companies are indeed known to supply power on an interruptible basis. In return for a reduction in their electricity bills, some customers give the company the right to cut off part of their supply when demand rises close to generating capacity.     

Demand uncertainty and capacity utilization in airlines

This paper studies the relationship between demand uncertainty—the key source of excess capacity—and capacity utilization in the US airline industry. We present a simple theoretical model that predicts that lower demand realizations are associated with higher demand volatility. This prediction is strongly supported by the results of estimating a panel GARCH framework that pools unique data on capacity utilization across different flights and over various departure dates. A one unit increase in the standard deviation of unexpected demand decreases capacity utilization by 21 percentage points. The estimation controls for unobserved time-invariant specific characteristics as well as for systematic demand fluctuations.     

Entry preemption through capacity expansion in the U.S. titanium industry

This study investigates the impact of expected excess capacity on the probability of firm entry into a single-product oligopoly, specifically, the U.S. titanium industry. Predicted values for excess capacity as well as its components, production, and capacity are generated. By disentangling the components of excess capacity and estimating them independently, it is possible to separate incumbents' discretionary actions regarding capacity expansion, which may preempt entry, from the effects of underlying cycles in demand, which subsequently affect production. These predicted values are utilized in logit models which indicate that expected levels of capacity expansion did appear to decrease the probability of firm entry, while expected levels of production and excess capacity had no effect on the probability of entry into the U.S. titanium industry.     

Small noise asymptotics for a stochastic growth model

We develop analytic asymptotic methods to characterize time-series properties of nonlinear dynamic stochastic models. We focus on a stochastic growth model which is representative of the models underlying much of modern macroeconomics. Taking limits as the stochastic shocks become small, we derive a functional central limit theorem, a large deviation principle, and a moderate deviation principle. These allow us to calculate analytically the asymptotic distribution of the capital stock, and to obtain bounds on the probability that the log of the capital stock will differ from its deterministic steady-state level by a given amount. This latter result can be applied to characterize the probability and frequency of large business cycles. We then illustrate our theoretical results through some simulations. We find that our results do a good job of characterizing the model economy, both in terms of its average behavior and its occasional large cyclical fluctuations.     

Global sunspots in OLG models: Theory and computational analysis

This paper discusses sunspots equilibria in a context that is general in the sense that: (i) the evolution of the system takes place in a general state space (i.e., a space which is not necessarily finite or even countable); and (ii) the orbits of the unperturbed, deterministic component of the system converge to subsets of the state space which can be more complicated than a stationary state or a periodic orbit, i.e., they can be aperiodic or chaotic. This problem is represented mathematically as a system of stochastic difference equations the invariant probability distributions of which correspond to stationary sunspots equilibria. The conditions for stochastic stability are recalled and the theoretical results are applied to a model of overlapping generations with individuals living three periods. A computational analysis of this model is provided, covering the basic different cases suggested by the theory.     

Debt as a collusive device in an oligopoly supergame

This paper explores the impact of debt holdings on the output decisions of firms in an oligopoly supergame with stochastic demand fluctuations. It is demonstrated that when perfect collusion is not feasible then there exist circumstances in which increased debt holdings may facilitate tacit collusion. This occurs because higher debt levels act as a credible commitment device which lowers the payoffs accruing to a firm when it defects from the tacitly collusive equilibrium. It is further shown that in these circumstances firms may have an incentive to hold debt for strategic purposes which promote collusion.     

Demand Aggregation and the Weak Axiom of Stochastic Revealed Preference

We address the problem of aggregating demand across a group of consumers, who are identical in terms of wealth and face identical price vectors, but vary in their chosen consumption bundles. We show that, when a stochastic demand function is constructed to aggregate a number of deterministic demand functions, satisfaction of the weak axiom of stochastic revealed preference by this stochastic demand function is weaker than the restriction that every underlying deterministic demand function satisfy Samuelson's weak axiom of revealed preference. Journal of Economic Literature Classification Number: D11.     

Stochastic Demand for Hospitals and Optimizing "Excess" Bed Capacity

This paper addresses the issue of hospital bed capacity by considering the stochastic demand for United States hospitals. An equilibrium condition for the optimal number of "excess" beds is derived and applied using a cost function estimated with a panel data model for the period 1987-1992. Results indicate that it may be difficult to justify the costliness of existing levels of empty hospital beds. The Department of Justice and the Federal Trade Commission should be cognizant of the potential effects of hospital mergers on undesirable excess bed capacity.     

人民币汇率波动与货币政策调控难度

文章采用动态随机一般均衡（DSGE）模型研究了中国货币政策实施时不能忽略的人民币汇率波动特征。文章构建了人民币汇率波动与中国货币政策及其宏观经济系统影响机制的理论模型,并在模型参数校准的基础上进行了政策模拟。研究结果表明,较大的人民币汇率波动会在一定程度上减弱中国货币政策的调控效果,但是对每个变量冲击响应的影响程度有所不同。较大的人民币汇率波动将显著干扰货币政策对宏观经济需求的调控,人民币汇率升值波动幅度较大时,货币政策对需求变量的调控作用会减弱,但不会影响相关需求变量在不同时点的冲击响应走势特征。较大的汇率波动会减弱利率上行对出口的负面影响,有利于缓解货币政策对出口的负面冲击,但会导致贸易条件（出口价格和进口价格的比值）进一步恶化。     

The dynamics of efficient asset trading with heterogeneous beliefs

This paper analyzes the dynamic properties of portfolios that sustain dynamically complete markets equilibrium when agents have heterogeneous priors. We argue that the conventional wisdom that belief heterogeneity generates continuous trade and significant fluctuations in individual portfolios may be correct but it needs some qualifications. We consider an infinite horizon stochastic endowment economy populated by many Bayesian agents with heterogeneous priors over the stochastic process of the states of nature. Our approach hinges on studying the portfolios that decentralize Pareto optimal allocations. Since these allocations are typically history dependent, we propose a methodology to provide a complete recursive characterization when agents believe that the process of states of nature is i.i.d. but disagree about the probability of the states. We show that even though heterogeneous priors within that class can indeed generate genuine changes in the portfolios of any dynamically complete markets equilibrium, these changes vanish with probability one if the true process consists of i.i.d. draws from a common distribution and the support of some agent's prior belief contains the true distribution. Finally, we provide examples in which asset trading does not vanish because either (i) no agent learns the true conditional probability of the states or (ii) some agent does not know the true process generating the data is i.i.d.     

Seasonality and stochastic trends in German consumption and income, 1960.1–1987.4

The quarterly time series of German consumption and income are analyzed with respect to seasonality and stochastic trends. It emerges that both variables can be appropriately described by a periodically integrated autoregression. An implication is that the stochastic trend and the seasonal fluctuations are not independent for each of the univariate series. In order to test for cointegration across the two series, we propose several methods which take account of the relationship between seasons and trends in the univariate series. Some of these methods boil down to extracting the stochastic trend from the univariate series in a first step and to relating these trends using cointegration techniques in a second step. Another method is an extension of the Johansen cointegration testing approach to periodic vector autoregressions. Monte Carlo simulations are used to evaluate the empirical performance of the various methods. The main empirical result is that only in the first quarter there seems to be cointegration between German consumption and income.     

An Incentive Water Pricing Policy for Sustainable Water Use

By adopting the Water Framework Directive (WFD), the European Commission (EC) and the European Council made recommendations for water pricing policies in European Union (EU) member states with a view to enhancing the sustainability of water resources. Clearly, the directive integrates economic instruments in environmental policies to provide incentives for the sustainable use of water resources. Our analysis will focus on public water utilities, required to be financially self-sufficient, facing demand and capacity shocks. The paper deals with the simultaneous determination of incentive pricing policies and investment rules under an ex~ante maximum demand charge. We will characterize the welfare-optimal capacity selection rule and the welfare-optimal maximum demand pricing rule. Heterogeneous consumers demands are considered when tariffs are set ex~ante, before demands are known. Our results are state-contingent nonlinear pricing that responds to demand fluctuations and capacity constraints.      

A welfare analysis of tariffs and equivalent quotas under demand uncertainty: Implications for tariffication

Under market demand uncertainty, we show that quotas can result in a welfare advantage over tariffs for an importing country despite that its government does not capture any quota rents. Specifically, the conditions under which an equivalent quota yields higher expected welfare than a tariff are shown to depend on a set of economic variables. These variables include the initial tariff rate, the relative efficiency in production between home and foreign firms, the probability distribution of random demand shocks that make the quota binding or non-binding under uncertainty, as well as the variance of the stochastic market demand. The analysis of this paper has welfare implications for tariffication.     

The Evolution of Social and Economic Networks

We examine the dynamic formation and stochastic evolution of networks connecting individuals. The payoff to an individual from an economic or social activity depends on the network of connections among individuals. Over time individuals form and sever links connecting themselves to other individuals based on the improvement that the resulting network offers them relative to the current network. In addition to intended changes in the network there is a small probability of unintended changes or errors. Predictions can be made regarding the likelihood that the stochastic process will lead to any given network at some time, where the stochastic process selects from among the statically stable networks and cycles. We apply these results to examples including the Gale-Shapley marriage problem. Thus the paper achieves two goals. First, it outlines a dynamic solution concept for networks. Second, it applies this concept to matching problems. Journal of Economic Literature Classification Numbers: A14, D20, J00.     

Asymmetries in price and quantity adjustments by the competitive firm

Focusing on the crucial role of inventory carry-overs in the production and sales decision, we describe the profit maximizing behavior of a dynamic competitive firm facing random prices. Each firm's behavior is incorporated into a stochastic equilibrium model of the competitive industry with uncertain demand. The industry model exhibits asymmetric cyclical fluctuations of the “Keynesian” sort: when demand is weak, output contracts while price holds at a fixed floor; when demand is strong, price increases as output is constrained by a ceiling. Even in a pure world of constant returns, without increasing costs, the inability to instantaneously coordinate production and sales along with the existence of inventories is sufficient to yield a “backward L” shaped supply curve for the short run.     

Fixed-term contracts as a source of labour demand fluctuations

Employment fluctuations are one of the central issues in the business cycle literature. The fluctuations depend crucially not only on the economic conditions but also on the labour market institutions. Since most previous studies have assumed indefinite-term contracts (ITC) implicitly, the implications of fixed-term contracts (FTC) on dynamic labour demand have been rather overlooked. This article investigates dynamic labour demand of a firm with FTC to show that the employment fluctuations under FTC can be totally different from those under ITC. In particular, a productivity shock that takes place at a future date generates the current fluctuations in employment under FTC, while it does not under ITC.     

Price-making in a competitive market

An attempt is made to analyze the behavior of a price-maker in a purely competitive market. Assuming the price-maker maximizes expected profit subject to the constraint of satisfying periodic excess demand, we derive characteristics of his optimal prices as they depend on current state variables and then obtain properties of the expectation and variance of the long-run stationary probability distribution of price.