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101.
Agriculture remains sensitive to variation in rainfall and temperature. Fortunately, our ability to predict the lower frequency variation in the earth's atmosphere is increasing rapidly. While information cannot affect the underlying source of variability, it allows unexpected shocks to be anticipated and acted upon. This paper develops and analyzes an intertemporal Ricardian trade model with Bayesian beliefs. Results in this paper show that improved climate prediction reduces expected prices, but increases price variability. In addition, trade is crucial to realizing the potential benefits of climate prediction. The value of climate prediction is highest with both storage and trade, and falls by over 300% when a country is in autarky.  相似文献   
102.
如今,全球都笼罩在经济衰退之中.如果下一个就要轮到贵公司,你该怎么办?当然你要尽力保证企业财务的稳定.但更重要的是,你还必须了解公司在衰退结束后的目标设计.如果你知道企业的发展方向和如何实现这一目标,那么衰退时期是改善公司相对战略地位的好时机.  相似文献   
103.
In this paper we illustrate how certain design problems can be simplified by reparametrization of the response function. This alternative viewpoint provides further insights than the more traditional approaches, like minimax, Bayesian or sequential techniques. It will also improve a practitioner’s understanding of more general situations and their “classical” treatment.  相似文献   
104.
Encouraged by a highly expansionary economic policy, the global economy is enjoying a rapid upturn. Utilisation of capacity is high in many sectors, particularly in the growth centres of the USA and East Asia, where China leads the field. With inflationary risks on the increase, most countries are now shifting the focus of economic policy. Fiscal policy in particular can be expected to provide little in the way of further stimulus. In addition, there has been a turnaround in interest rates in many countries. Yet how quickly can the monetary reins be tightened without jeopardising growth or endangering price stability?  相似文献   
105.
Ethics in business and economics is often attacked for being too superficial. By elaborating the conclusions of two such critics of business ethics and welfare economics respectively, this article will draw the attention to the “ethics behind” these apparently well-intended, but not always convincing constructions, by help of the “fundamental ethics” of Emmanuel Levinas. To Levinas, responsibility is more basic than language, and thus also more basic than all social constructions. Co-operation relations in organizations, markets and value networks are generated from personal relations and personal responsibilities. It is not sufficient to integrate ethics in an impersonal, rational system, neither in business organizations nor in the world economy. Ethics has its source not in rationality, but in the personal.  相似文献   
106.
The margin system is the first line of defense against the default risk of a clearinghouse. From the perspectives of a clearinghouse, the utmost concern is to have a prudential system to control the default exposure. Once the level of prudentiality is set, the next concern will be the opportunity cost of the investors, because high opportunity cost discourages people from hedging futures, and thus defeats the function of a futures market. In this article, we first develop different measures of prudentiality and opportunity cost. We then formulate a statistical framework to evaluate different margin‐setting methodologies, all of which strike a balance between prudentiality and opportunity cost. Three margin‐setting methodologies, namely, (1) using simple moving averages; (2) using exponentially weighted moving averages; (3) using a GARCH approach, are applied to the Hang Seng Index futures. Keeping the same prudentiality level, it is shown that the one using a GARCH approach by and large gives the lowest average overcharge. © 2004 Wiley Periodicals, Inc. Jrl Fut Mark 24:117–145, 2004  相似文献   
107.
This article uses a nonparametric test based on the arc‐sine law (see, e.g., Feller, 1965 ), which involves comparing the theoretical distribution implied by an intraday random walk with the empirical frequency distribution of the daily high/low times, in order to address the question of whether the abandonment of pit trading has been associated with greater market efficiency. If market inefficiencies result from flaws in the market microstructure of pit trading, they ought to have been eliminated by the introduction of screen trading. If, on the other hand, the inefficiencies are a reflection of investor psychology, they are likely to have survived, unaffected by the changeover. We focus here on four cases. Both the FTSE‐100 and CAC‐40 index futures contracts were originally traded by open outcry and have moved over to electronic trading in recent years, so that we are able to compare pricing behavior before and after the changeover. The equivalent contracts in Germany and Korea, on the other hand, have been traded electronically ever since their inception. Our results overwhelmingly reject the random‐walk hypothesis both for open‐outcry and electronic‐trading data sets, suggesting there has been no increase in efficiency as a result of the introduction of screen trading. One possible explanation consistent with our results would be that the index futures market is characterized by intraday overreaction. © 2004 Wiley Periodicals, Inc. Jrl Fut Mark 24:337–357, 2004  相似文献   
108.
This article analyzes the effects of the length of hedging horizon on the optimal hedge ratio and hedging effectiveness using 9 different hedging horizons and 25 different commodities. We discuss the concept of short‐ and long‐run hedge ratios and propose a technique to simultaneously estimate them. The empirical results indicate that the short‐run hedge ratios are significantly less than 1 and increase with the length of hedging horizon. We also find that hedging effectiveness increases with the length of hedging horizon. However, the long‐run hedge ratio is found to be close to the naïve hedge ratio of unity. This implies that, if the hedging horizon is long, then the naïve hedge ratio is close to the optimum hedge ratio. © 2004 Wiley Periodicals, Inc. Jrl Fut Mark 24:359–386, 2004  相似文献   
109.
The primary purpose of this paper was to empirically explore some of the reasons that logistics has become more important, or salient, in comparison to other functions within the firm. A survey of 296 managers across multiple industries in the U.S. found logistics becomes more important within the firm when the industry increases in uncertainty, when there is an emphasis on time‐based competition, when there is greater adoption of information technology, and when there is an emphasis on cross‐functional integration.  相似文献   
110.
THE SQUARED ORNSTEIN-UHLENBECK MARKET   总被引:2,自引:0,他引:2  
We study a complete market containing J assets, each asset contributing to the production of a single commodity at a rate that is a solution to the squared Ornstein-Uhlenbeck (Cox-Ingersoll-Ross) SDE. The assets are owned by K agents with CRRA utility functions, who follow feasible consumption/investment regimes so as to maximize their expected time-additive utility from consumption. We compute the equilibrium for this economy and determine the state-price density process from market clearing. Reducing to a single (representative) agent, and exploiting the relation between the squared-OU and squared-Bessel SDEs, we obtain closed-form expressions for the values of bonds, assets, and options on the total asset value. Typical model parameters are estimated by fitting bond price data, and we use these parameters to price the assets and options numerically. Implications for the total asset price itself as a diffusion are discussed. We also estimate implied volatility surfaces for options and bond yields.  相似文献   
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