风险厌恶与国有寡占市场的资源配置效率——以我国成品油市场为例

作为传统寡占理论与我国国情相结合的产物,国有寡占市场受到越来越多的关注。本文以风险厌恶倾向为切入点,从缺少职业经理人市场、优越的生存环境和目标多重性三方面分析了国有寡占企业风险厌恶倾向的成因,并构建理论模型分析这种风险厌恶倾向对国有寡占市场资源配置效率的影响。结果表明,风险厌恶倾向使国有寡占企业面对成本风险时,价格和产量相对利润最大化值分别升高和降低,面对需求风险时,价格和产量同时低于利润最大化值,两种情况都使国有寡占市场资源配置效率降低,而固定成本的升高会进一步加大资源配置效率的损失。本文最后以我国石化行业成品油市场为案例,验证理论模型的结论,并提出了政策建议。     

Information Markets and the Comovement of Asset Prices

Traditional asset pricing models predict that covariance between prices of different assets should be lower than what we observe in the data. This paper introduces markets for information that generate high price covariance within a rational expectations framework. When information is costly, rational investors only buy information about a subset of the assets. Because information production has high fixed costs, competitive producers charge more for low-demand information than for high-demand information. The low price of high-demand information makes investors want to purchase the same information that others are purchasing. When investors price assets using a common subset of information, news about one asset affects the other assets' prices; asset prices comove. The cross-sectional and time-series properties of comovement are consistent with this explanation.     

Rent Seeking and Allocative Efficiency

This paper considers a rent‐seeking game (specifically, a winner‐takes‐all contest) with incomplete information. By allowing for sequential moves, a Bayesian‐Stackelberg equilibrium can be constructed. It can be shown that, at the Bayesian‐Stackelberg equilibrium, it is always possible that the allocative efficiency argument fails. That is, there are cases in which the Stackelberg follower is more efficient but loses the contest. Using a specific class of distributions, it is also shown that sometimes the corrupt official will choose the Bayesian‐Stackelberg equilibrium over the Bayesian‐Nash equilibrium in order to maximise the expected bribe revenue. That is, when designing the rules of the rent‐seeking game, the dynamic nature of competition will be taken into account.     

Incomplete Markets, Transitory Shocks, and Welfare

Although equilibrium allocations in models with incomplete markets are generally not Pareto-efficient, it is often argued that quantitative welfare losses from missing assets are small when time horizons are long and shocks are transitory. In this paper we use a computational analysis to show that even in the simplest infinite horizon model without aggregate uncertainty welfare losses can be substantial. Furthermore we show that in this model welfare losses from incomplete markets do not necessarily disappear when one considers calibrations of the model in which agents become very patient. We argue that when the economic model is calibrated to higher frequency data, the period persistence of negative income shocks must increase as well. In this case the welfare loss of incomplete markets remains constant even as agents' rate of time preference tends to one. Journal of Economic Literature Classification Numbers: D52, D58, D60.     

Demand Uncertainty, Incomplete Markets, and the Optimality of Rationing

When the arrival of traders at the market is stochastic, and it is impossible for traders who might arrive to meet ex ante, then Walrasian spot-market clearing presents consumers with price-risk and is typically not Pareto optimal. Instead, with an indivisible good and a divisible numeraire, the first-best can be achieved by an “Exchange” selling raffle tickets at a fixed price. When only spot market trading is feasible and consumers cannot commit to pay unless they purchase the indivisible good, efficiency implies price-fixing with rationing. Potential disadvantages of black markets and scalping are discussed.Journal of Economic LiteratureClassification Numbers: D45, D52, D8.     

Information Efficiency in Betting Markets: a Survey

The concept of information efficiency is central to many studies of financial markets, and these studies have been well surveyed to date. A betting market is an example of a simple financial market, but one which offers researchers the added advantage that it is characterized by a well-defined termination point at which each asset (or bet) possesses a definite value. In consequence, it is much more convenient to use this particular context to formulate tests of information efficiency, and from these tests to draw useful conclusions. This paper surveys the rapidly growing literature which has to date addressed this issue of information efficiency in betting markets.     

Price Convergence and Information Efficiency in German Natural Gas Markets

In 2007, Germany changed network access regulation in the natural gas sector and introduced a so‐called entry–exit system. The spot market effects of the reregulation remain to be examined. We use cointegration analysis and a state space model with time‐varying coefficients to study the development of natural gas spot prices in the two major trading hubs in Germany and the interlinked spot market in the Netherlands. To analyse information efficiency in more detail, the state space model is extended to an error correction model. Overall, our results suggest a reasonable degree of price convergence between the corresponding hubs. Market efficiency in terms of information processing has increased considerably among Germany and the Netherlands.     

Information,Pricing and Efficiency in Cash and Futures Markets: The Case of Hogs

The price leadership roles among hog cash and futures markets are assessed to locate points of price discovery and to examine flows of information among these markets. Several years of data are analyzed using lead/lag causality analysis and strength of linear causality measures. Although significant instantaneous relationships exist among hog cash and futures markets, one-way causality tests indicate that generally the futures market dominates cash hog markets in the price discovery process.     

Duplicating and Pricing Contingent Claims in Incomplete Markets

The paper studies the problem of pricing contingent claims in the situation where the constraints imposed on an investor's portfolios are important. There are two types of rule of constraint: under a rigid rule, an investor must strictly limit his portfolios inside the constraint; under an elastic rule, an investor pays a penalty when the constraint is violated. The central problem of pricing a contingent claim is to determine the initial investment required to duplicate the contingent claim. The following results are obtained: (i) under elastic rules, the cost to duplicate a contingent claim exists and is unique;(ii) this cost depends nonlinearly and convexly on the contingent claim;(iii) the cost under rigid rules resulting from passing the penalty to infinity is also a nonlinear and convex function of the contingent claim. Owing to this nonlinearity, the cost of duplication may be or may not be the nonarbitrage price of the contingent claim; this depends on how the market organizes the production of contingent claims. The conclusion that the cost of duplication is a convex function of the contingent claim provides an explanation for why the service of providing contingent claims is often a highly profitable business. The main mathematical tool in the analysis is backward stochastic differential equations (BSDEs). In fact the cost to duplicate a contingent claim is the solution of a BSDE in which the contingent claim is the terminal value.     

Fiscal Policy with Heterogeneous Agents and Incomplete Markets

I undertake a quantitative investigation into the short run effects of changes in the timing of proportional income taxes for model economies in which heterogeneous households face a borrowing constraint. Temporary tax changes are found to have large real effects. In the benchmark model, a temporary tax cut increases aggregate consumption on impact by around 29 cents for every dollar of tax revenue lost. Comparing the benchmark incomplete-markets model to a complete-markets economy, income tax cuts provide a larger boost to consumption and a smaller investment stimulus when asset markets are incomplete.     

Income Taxation, Endogenous Factor Prices and Production Efficiency

In an analysis of a two‐type income tax model with endogenous wages, this paper shows that production efficiency is violated in the optimum with (i) non‐linear and (ii) linear income taxation if and only if a distortionary tax schedule is implemented. These findings complement earlier results of the literature. In passing, it is also shown that optima with non‐linear redistributive income taxation cannot be identified with the redistributive regime if the assumption of endogenous wages is taken seriously.     

A Brief Overview of the Economics of Incomplete Markets

This paper was motivated by my participation in the Economic Theory Symposium of the 1988 Australian Economics Congress, Canberra. It represents only one perspective on an immense literature. As the reader will notice, I have often referred to my own work. for two reasons. The first is because it is what I know best, the second is to provide an illustration of the in efficiency resulting from the incentive constraints editors face in contracting for surveys .     

基于股价异常波动的中国股市监管效率实证分析

证券市场监管究竟是有效的还是无效的,在理论上存在着长期争论。目前,证券市场监管的有效性只能通过实证的方法加以甄别。文章将监管股市的政策手段分为经济手段、法律手段、舆论手段和行政手段,并采用事件研究法对股价异常波动点对应的四种监管股市的政策事件产生的市场反应进行研究。研究结果表明:股价异常波动点的分布与监管政策事件存在着明显的对应关系,监管政策事件对中国股票市场波动的影响较大;近年来证券市场监管的力度在加强,监管的效率逐渐提高;相对于其他监管手段而言,经济手段的监管效率较高。     

On the Effects of Suggested Prices in Gasoline Markets

There is a widespread suspicion that suggested prices act as a focal point for individual firms when setting their prices. Oil companies announce suggested prices for gasoline stations in the Dutch retail market. We show that, compared to the gasoline spot market price, suggested prices contain additional information that explains retail price changes. We conclude that suggested prices have a horizontal coordinating effect in the sense that retail prices react to information that suggested prices contain and that is unrelated to firms’ costs (i.e., the information that firms use under normal competitive conditions).     

不完全信息、反倾销威胁与最优出口贸易政策

通过扩展Brander和Spencer(1985)的基本模型,本文首先证明了,在反倾销威胁下,基于完全信息假设的最优出口贸易政策要求出口国政府给予低成本企业更高的出口补贴或更低的出口征税,在无效激励机制下必然导致出口企业隐匿自己的真实成本类型,基于完全信息假设的最优出口贸易政策失效。在此基础上,本文进一步论证了不完全信息和反倾销威胁下激励相容的最优出口贸易政策,该政策要求出口国政府依据进口国国内要求保护压力的大小,采用不同的出口征税和一次性转移支付政策组合,激励出口企业如实报告成本类型,并使国家整体福利最大化。