Comparative Statics,Informativeness, and the Interval Dominance Order

We identify a new way to order functions, called the interval dominance order, that generalizes both the single crossing property and a standard condition used in statistical decision theory. This allows us to provide a unified treatment of the major theorems on monotone comparative statics with and without uncertainty, the comparison of signal informativeness, and a non‐Bayesian theorem on the completeness of increasing decision rules. We illustrate the concept and results with various applications, including an application to optimal stopping time problems where the single crossing property is typically violated.     

Farms,Families, and Markets: New Evidence on Completeness of Markets in Agricultural Settings

The farm household model has played a central role in improving the understanding of small‐scale agricultural households and non‐farm enterprises. Under the assumptions that all current and future markets exist and that farmers treat all prices as given, the model simplifies households' simultaneous production and consumption decisions into a recursive form in which production can be treated as independent of preferences of household members. These assumptions, which are the foundation of a large literature in labor and development, have been tested and not rejected in several important studies including Benjamin (1992). Using multiple waves of longitudinal survey data from Central Java, Indonesia, this paper tests a key prediction of the recursive model: demand for farm labor is unrelated to the demographic composition of the farm household. The prediction is unambiguously rejected. The rejection cannot be explained by contamination due to unobserved heterogeneity that is fixed at the farm level, local area shocks, or farm‐specific shocks that affect changes in household composition and farm labor demand. We conclude that the recursive form of the farm household model is not consistent with the data. Developing empirically tractable models of farm households when markets are incomplete remains an important challenge.     

Prices and Portfolio Choices in Financial Markets: Theory,Econometrics, Experiments

Many tests of asset‐pricing models address only the pricing predictions, but these pricing predictions rest on portfolio choice predictions that seem obviously wrong. This paper suggests a new approach to asset pricing and portfolio choices based on unobserved heterogeneity. This approach yields the standard pricing conclusions of classical models but is consistent with very different portfolio choices. Novel econometric tests link the price and portfolio predictions and take into account the general equilibrium effects of sample‐size bias. This paper works through the approach in detail for the case of the classical capital asset pricing model (CAPM), producing a model called CAPM+ε. When these econometric tests are applied to data generated by large‐scale laboratory asset markets that reveal both prices and portfolio choices, CAPM+εis not rejected.     

Efficiency Wage,Fixed Employment Costs,and Dual Labour Markets

The standard efficiency wage‐based explanation of labour market dualism hinges on the existence of differences in monitoring across sectors. The paper proposes fixed employment costs as an alternative source of wage differentials for homogeneous workers. It shows that firms with larger fixed costs pay higher wages in order to elicit more effort from their workers, and tend to have higher capital/labour ratio and labour productivity. The model generates both involuntary unemployment and involuntary confinement in the secondary sector: high effort–high wage jobs are preferred to low effort–low wage jobs and either are preferred to unemployment. The proposed framework can also account for the various types of treatment of marginal jobs in primary sector firms envisaged by Doeringer and Piore (Internal Labour Markets and Manpower Analysis, 1971). In particular, an increase in fixed costs beyond a certain level may induce primary sector firms to restructure, segment production, and enter the secondary sector, thus converting their jobs into secondary jobs. From a welfare point of view, we cannot state in general the desirability of subsidizing fixed employment costs; however, we show that an employment subsidy financed by a wage tax is able to increase employment with no loss in terms of production.     

周日历效应传递吗?——伦敦和上海黄金市场的比较

首次系统探讨上海黄金市场从成立(2002年10月30日)至2007年6月29日期间收益和波动的周日历效应,并进一步研究与同期伦敦黄金市场周日历效应之间的关系。结果表明:上海黄金市场存在收益周一、周四正效应,波动周一、周三、周五高效应和周二、周四低效应,周日历效应整体显著;伦敦黄金市场存在周三、周五收益正效应,周三高波动和周五低波动效应,但整体的周日历效应并不显著;伦敦黄金市场收益周日历效应可以显著解释上海黄金市场收益周日历效应,收益周日历效应具有跨市场传递性;上海黄金市场的价格发现能力和有效性皆逊于伦敦;此外,两个市场都表现出杠杆效应。     

Uncertainty and Risk in Financial Markets

This paper considers a general equilibrium model in which the distinction between uncertainty and risk is formalized by assuming agents have incomplete preferences over state‐contingent consumption bundles, as in Bewley (1986). Without completeness, individual decision making depends on a set of probability distributions over the state space. A bundle is preferred to another if and only if it has larger expected utility for all probabilities in this set. When preferences are complete this set is a singleton, and the model reduces to standard expected utility. In this setting, we characterize Pareto optima and equilibria, and show that the presence of uncertainty generates robust indeterminacies in equilibrium prices and allocations for any specification of initial endowments. We derive comparative statics results linking the degree of uncertainty with changes in equilibria. Despite the presence of robust indeterminacies, we show that equilibrium prices and allocations vary continuously with underlying fundamentals. Equilibria in a standard risk economy are thus robust to adding small degrees of uncertainty. Finally, we give conditions under which some assets are not traded due to uncertainty aversion.     

全球金融危机下的股票市场波动跳跃研究——基于高频数据的中美比较分析

本文以雷曼破产日至2009年1月底这段时期内上证综指、恒生指数以及S&P500指数的日内高频数据作为研究对象,采用跳跃显著性检验方法和扩展HAR模型,对波动跳跃特征进行了实证研究.结果表明:雷曼危机导致股市波动的显著提高,但中国内地股市受到的影响最小;中国香港股市成为波动跳跃发生频率最高、跳跃幅度最大的市场,且波动跳跃主要发生在夜间休市时间内;雷曼危机使得波动率模型的预测精度大大降低,股市风险变得更加难以预测,对于新兴市场来说这一现象更加明显.     

On Strategy,Typologies and the Adoption of Technological Innovations in Industrial Markets

This paper investigates the role of strategy in the timing of adoption of technological innovation by industrial firms. In the course of this investigation we bring together and consolidate theoretical insights and empirical evidence from diverse yet fundamentally related streams of research. Strategy is placed within the wider context of the many factors that have been found to influence the timing of a firm's decision to adopt a technological innovation, and conjectures about its precise role are debated. The paper concludes with suggestions towards a synthesis of the highly fragmented work in the area, and identifies key directions for research aimed at a better understanding of the innovation adoption decision in contemporary firms and the interrelationships of the many factors influencing this decision.     

Herding and Contrarian Behavior in Financial Markets

Rational herd behavior and informationally efficient security prices have long been considered to be mutually exclusive but for exceptional cases. In this paper we describe the conditions on the underlying information structure that are necessary and sufficient for informational herding and contrarianism. In a standard sequential security trading model, subject to sufficient noise trading, people herd if and only if, loosely, their information is sufficiently dispersed so that they consider extreme outcomes more likely than moderate ones. Likewise, people act as contrarians if and only if their information leads them to concentrate on middle values. Both herding and contrarianism generate more volatile prices, and they lower liquidity. They are also resilient phenomena, although by themselves herding trades are self‐enforcing whereas contrarian trades are self‐defeating. We complete the characterization by providing conditions for the absence of herding and contrarianism.     

Entry and Exit in OTC Derivatives Markets

We develop a parsimonious model to study the equilibrium and socially optimal decisions of banks to enter, trade in, and possibly exit, an OTC market. Although we endow all banks with the same trading technology, banks' optimal entry and trading decisions endogenously lead to a realistic market structure composed of dealers and customers with distinct trading patterns. We decompose banks' entry incentives into incentives to hedge risk and incentives to make intermediation profits. We show that dealer banks enter more than is socially optimal. In the face of large negative shocks, they may also exit more than is socially optimal when markets are not perfectly resilient.     

Gray Markets,A Product of Demand Uncertainty and Excess Inventory

Diverting large quantities of goods from authorized distribution channels to unauthorized or “gray market” channels, albeit legal, significantly affects both firms and consumers due to effects on price, revenue, service and warranty availability, and product availability. In this paper we consider mechanisms by which the uncertainty surrounding inventory ordering decisions drives gray markets. We start with a minimal stochastic supply chain model composed of a producer and a retailer; then we restructure the model to add a distributor whereby the distributor and authorized retailer have the option of diverting inventory to a gray market. Our analysis sheds light on three issues: impacts of diversion on the various supply chain participants, strategies producers could use to combat or exploit gray markets, and important considerations for authorized retailers trying to set optimal order quantities in the presence of a gray market. Our analysis yields new insights into the behavior and impact of gray markets, which can inform management strategies and policies for confronting them.     

双长记忆GARCH族模型的预测能力比较研究——基于沪深股市数据的实证分析

GARCH族模型在金融风险的度量中有着广泛的应用。在考虑股市收益率和波动率序列双长记忆性的基础上,基于上证综合指数和深圳成份指数的日收盘价序列,从证券投资风险量化的角度,引入受险值VaR和相对正确符号指标PCS作为模型预测误差衡量指标,比较分析了双长记忆GARCH族模型在不同分布假设情况下的的拟合与预测精度。结果显示:偏t分布能较好描述沪深股市的厚尾特征;在较小的VaR水平下ARFIMA(2,d₁,0)-FIAPARCH(1,d₂,1)-skt模型对股市波动风险具有较强的预测能力,而ARFIMA(2,d₁,0)-HYGARCH(1,d₂,1)-skt对股市的涨跌趋势具有较强的预测能力。     

证券投资基金、资本市场及货币政策传导机制

从宏观和市场发展层面上,在SVAR分析框架内,结合有向非循环图技术和Granger因果方法,对2006年至2015年中国证券投资基金与M₂、M₀、SHIBOR、股票、债券以及居民存款之间的联动关系进行分析,研究证券投资基金与股票、债券、居民存款等金融市场和服务之间的因果联系以及证券投资基金发展对货币政策在资本市场的传导机制的影响效果。 研究结果表明,股票与证券投资基金存在紧密的因果互动关系,但它们与其他变量之间还没形成有效联动,表明当前中国金融体系发展还不完善,市场还处于分割状态。相对于M₀和M₂,SHIBOR与金融市场中主要指标变量之间相关性更小,反映了中国以货币供应量作为主要中介目标的现状以及利率还未完全市场化的事实。股票与证券投资基金相互冲击较大,但与其他变量的互动作用较小,说明当前中国金融市场还不成熟,证券投资基金的投资渠道狭窄,扎堆于高风险股票类资本市场,加剧了股票市场剧烈波动和风险集中。M₀、M₂和SHIBOR的波动性对基金、债券和股票的冲击较小,同时,它们自身受基金和股票冲击也不大。但债券对M₀具有较强冲击作用,说明当前的货币政策与资本市场相互影响较小,货币政策通过资产价格传导渠道影响资本市场的功能尚未发挥。将计入证券投资基金的广义货币M⁺₂作为货币政策的中介目标,对改善货币政策对资本市场监测和调控效果不大,但对减小财政政策对货币政策冲击、提高中国货币政策执行稳定性和独立性有正面作用。尽管从Granger因果关系看,M⁺₂没有提高货币政策与金融市场的互动效果,但从DAG因果关系看,它改善了货币政策与资本市场同期因果互动关系,从而提高了货币政策对资本市场的敏感性。     

Incentives,Contracts, and Markets: A General Equilibrium Theory of Firms1

This paper takes steps toward integrating firm theory in the spirit of Alchian and Demsetz (1972) and Grossman and Hart (1986), contract theory in the spirit of Holmstrom (1979), and general equilibrium theory in the spirit of Arrow and Debreu (1954) and McKenzie (1959). In the model presented here, the set of firms that form and the contractual arrangements that appear, the assignments of agents to firms, the prices faced by firms for inputs and outputs, and the incentives to agents are all determined endogenously at equilibrium. Agents choose consumption—but they also choose which firms to join, which roles to occupy in those firms, and which actions to take in those roles. Agents interact anonymously with the (large) market, but strategically within the (small) firms they join. The model accommodates moral hazard, adverse selection, signaling, and insurance. Equilibria may be Pareto ranked.     

Market Structure and Multiple Equilibria in Airline Markets

We provide a practical method to estimate the payoff functions of players in complete information, static, discrete games. With respect to the empirical literature on entry games originated by Bresnahan and Reiss (1990) and Berry (1992), the main novelty of our framework is to allow for general forms of heterogeneity across players without making equilibrium selection assumptions. We allow the effects that the entry of each individual airline has on the profits of its competitors, its “competitive effects,” to differ across airlines. The identified features of the model are sets of parameters (partial identification) such that the choice probabilities predicted by the econometric model are consistent with the empirical choice probabilities estimated from the data. We apply this methodology to investigate the empirical importance of firm heterogeneity as a determinant of market structure in the U.S. airline industry. We find evidence of heterogeneity across airlines in their profit functions. The competitive effects of large airlines (American, Delta, United) are different from those of low cost carriers and Southwest. Also, the competitive effect of an airline is increasing in its airport presence, which is an important measure of observable heterogeneity in the airline industry. Then we develop a policy experiment to estimate the effect of repealing the Wright Amendment on competition in markets out of the Dallas airports. We find that repealing the Wright Amendment would increase the number of markets served out of Dallas Love.     

证券市场上的存货与羊群效应分析

用金融市场微观结构模型的序贯交易框架分析了证券市场上羊群效应的发生机制.结论表明即便在一维不确定性下,交易者之间存货的变化可能引起羊群效应.当交易者的存货较低时,容易发生买的羊群行为;反之,当交易者的存货较高时,容易发生卖的羊群行为.     

Measurement and Pricing of Risk in Insurance Markets

The theory and practice of risk measurement provides a point of intersection between risk management, economic theories of choice under risk, financial economics, and actuarial pricing theory. This article provides a review of these interrelationships, from the perspective of an insurance company seeking to price the risks that it underwrites. We examine three distinct approaches to insurance risk pricing, all being contingent on the concept of risk measures. Risk measures can be interpreted as representations of risk orderings, as well as absolute (monetary) quantifiers of risk. The first approach can be called an "axiomatic" one, whereby the price for risks is calculated according to a functional determined by a set of desirable properties. The price of a risk is directly interpreted as a risk measure and may be induced by an economic theory of price under risk. The second approach consists in contextualizing the considerations of the risk bearer by embedding them in the market where risks are traded. Prices are calculated by equilibrium arguments, where each economic agent's optimization problem follows from the minimization of a risk measure. Finally, in the third approach, weaknesses of the equilibrium approach are addressed by invoking alternative valuation techniques, the leading paradigm among which is arbitrage pricing. Such models move the focus from individual decision takers to abstract market price systems and are thus more parsimonious in the amount of information that they require. In this context, risk measures, instead of characterizing individual agents, are used for determining the set of price systems that would be viable in a market.     

本土创新、能力发展和竞争优势——中国激光视盘播放机工业的发展及其对政府作用的政策含义

认为中国工业发展应当遵循“比较优势”的观点实质上是要求政府放弃工业政策和技术政策 ,但在解释工业竞争力源泉上却贫乏无力。本研究通过对中国激光光盘播放机工业发展经验的分析证明 ,基于本土市场需求特点的产品创新以及企业在技术学习和能力发展上的努力 ,才是技术相对落后国家的企业能够在开放市场条件下获得竞争优势的原因。中国DVD工业目前遭到被征收高额专利费的困境 ,突出说明了中国工业发展在技术结构上所面临的制约。突破这种制约不仅要求中国企业努力在技术上爬升 ,而且要求中国政府采取积极的技术政策和工业政策 ,因为在全球化条件下的市场机制既不能有效地解决通用技术知识的供给问题 ,也不可能公正地分配来自技术知识的收益。