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841.
842.
Can economically efficient outcomes be obtained and sustained in the absence of externally enforced property rights? We study the evolutionary properties of a game that exhibits two well-defined Nash equilibria: one generates an inefficient outcome while the other set generates an efficient outcome supported by the potential for retaliation. Although standard forward-looking refinements eliminate the efficient equilibrium, neither equilibrium type satisfies strict evolutionary stability criteria. However, both types of equilibrium define strategies that are neutrally stable, which makes them vulnerable to drift in dynamic environments. We conduct computer simulation experiments in which players learn adaptively via a tournament selection mechanism called sophisticated experimentation. Our simulations demonstrate that while the system spends a disproportionately high proportion of time in the inefficient equilibrium set, the efficient equilibrium is pervasive as the system drifts back and forth between the equilibrium sets, never settling on one or the other.  相似文献   
843.
A First Assessment of Some Measures of Core Inflation for the Euro Area   总被引:1,自引:0,他引:1  
Abstract. Core inflation plays an important role in the deliberations of monetary policy-makers. In this paper we evaluate a number of measures of core inflation constructed using euro-area data. In addition to the traditional exclusion-type core measures, we examine two newer ones, documenting their properties and evaluating their performance in terms of their ability to track underlying or trend inflation in real time. We focus on core measures derived from the Harmonized Index of Consumer Prices (HICP) as the European Central Bank has chosen to define its mandate for price stability in terms of this index, and because this is the only index of consumer prices that is compiled in a comparable manner across all members of the European Union. We document significant excess kurtosis in the cross-section distribution of price changes in the euro area, and show that several categories of prices are more volatile than those typically excluded from traditional measures of core inflation. Contrary to what one might expect, traditional measures of core inflation are not significantly less volatile than headline measures. We document the superior performance of alternative measures of core inflation in tracking trend inflation on average, but show that none of the various measures of core gave significant advance warning of the pickup in trend inflation at the beginning of 1999.  相似文献   
844.
We develop a model in which the mode of acquisition conveys information concerning the value of the bidder. The model incorporates the possibility that offers containing both cash and stock can be made in a setting consistent with the U.S. tax code. We demonstrate that bidders with unfavorable private information about their equity value choose offers containing some stock to avoid the capital gains tax consequences of cash offers. The model yields a number of unique predictions about the construction of acquisition offers. We present evidence consistent with the model.  相似文献   
845.
In a participative bureaucracy, group-based employee participation mechanisms provide opportunities to reexamine old routines and to take advantage of informal shortcuts that employees have worked out on their own. Instead of proving to be dinosaurs, older and larger bureaucratically structured organizations are demonstrating a capability for adaptation and change and achieving new productivity advantages through such participative structures. For small firms, a participative bureaucracy is complementary to the productive use of information technology in the machining process.  相似文献   
846.
通过对油价波动的历史原因、市场内在因素和人为因素的分析可以看出,石油市场已进入一个新时期,油价将变得更加动荡,而且在波动中呈上升趋势。预计新的平均价位大体为每桶20美元。为此,石油公司应积极研究贸易策略,一方面设法使自身免受损失,另一方面还要寻求从价格波动中赢利。只有准备充分,才能够抗御油价的剧烈波动和周期性变化,进而获得生存与发展。  相似文献   
847.
Stop and Go Agricultural Policies with a Land Market   总被引:1,自引:0,他引:1  
This article studies the design of farm policy in the presence of asymmetric information about farmers' productivity, a government objective to insure farmers a minimum "parity" income, an endogenous land rent, and diminishing returns on alternative (nonprogram crop) land uses. In this setting, acreage set asides are never part of an optimal farm policy, although compensated acreage limits are. When there are new farmer entrants who cannot be excluded from farm programs, optimal policy takes the form of a pure voluntary acreage limitation—or "buyout"—program in which high-cost producers participate and low-cost producers do not.  相似文献   
848.
The introduction of unspanned sources of risk (and frictions) implies that option prices include a risk premium. Prima facie evidence of the existence of risk premia in option prices is contained in the implied volatility smile patterns reported in the literature. This article isolates the risk premium (defined as the simple difference between estimated and observed option prices) on options on U.K. Gilts, German Bunds, and U.S. Treasury bond futures using models that include price jumps and stochastic volatility. This study finds that single and multi‐factor stochastic volatility models with jumps may explain the empirical regularities observed in bond futures. © 2003 Wiley Periodicals, Inc. Jrl Fut Mark 23:169–215, 2003  相似文献   
849.
The Chicago Board Options Exchange concurrently listed European‐style and American‐style options on the Standard and Poor's 500 Index from April 2, 1986 through June 20, 1986. This unique time period allows for a direct measurement of the early exercise premium in American‐style index options. In this study, using ask quotes, we find average early exercise premiums ranging from 5.04 to 5.90% for calls, and from 7.97 to 10.86% for puts. Additionally, we are able to depict a potentially useful functional form of the early exercise premium. As in previous studies, we find some instances of negative early exercise premiums. However, a trading simulation shows that traders must be able to trade within the bid–ask spread to profit from these apparent arbitrage opportunities. © 2003 Wiley Periodicals, Inc. Jrl Fut Mark 23:287–313, 2003  相似文献   
850.
In this article, we examine the impact of 21 different types of scheduled macroeconomic news announcements on S&P 100 stock‐index option volume and implied volatility. We find that there is a 2‐h delay after the announcement before volume increases. However, there is an immediate increase in volatility, which slowly dissipates over several hours. Further analysis shows that most of the high volume and volatility after announcements come from the announcements that are considered bad news. That is, bad news creates high volatility and high volume, whereas good news elicits lower volume and is not associated with higher volatility. These results are not consistent with the predictions of any one model. We also find that the announcements that cause the largest reaction in the equity option market are Consumer Credit, Consumer Spending, Factory Inventories, NAPM, and Non‐Farm Payrolls. Six other announcements elicit a mild response. © 2003 Wiley Periodicals, Inc. Jrl Fut Mark 23:315–345, 2003  相似文献   
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