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991.
MARYELLEN R. KELLEY 《劳资关系》1996,35(3):374-399
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
992.
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
993.
The Nested PIGLOG Model: An Application to U.S. Food Demand 总被引:1,自引:0,他引:1
A new demand system is introduced, the Nested PIGLOG model, nesting thirteen other demand systems including five that are also new. This new model and its nested special cases are applied to models of U.S. food demand that include food-at-home (FAH), food-away-from-home (FAFH), and alcoholic beverages. Although nested tests and out-of-sample forecasting performance favor generalizing models to a certain degree, statistically insignificant improvements to in-sample-fit and even poorer out-of-sample forecast accuracy undermine further generalizations. Based on a subset of preferred models, FAFH is found to be price and income elastic compared to FAH which is price and income inelastic. 相似文献
994.
Robert G. Tompkins 《期货市场杂志》2003,23(2):169-215
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
995.
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
996.
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
997.
We investigate intraday bid‐ask spreads (BAS), volatility, and trading activity of thinly traded equity index futures contracts on the Singapore Exchange. Contrary to previous findings, we find a rather flat BAS pattern during the trading day. However, consistent with past findings, an increase in risk widens the spread and a higher trading activity reduces it. When trading occurs in a day, spreads are reduced. No significant difference in volatility between days with and without trades was detected. When trades occur, quote revisions increase, and it is positively related to the number of trades. An increase in the number of quote revisions increases the likelihood of a transaction, and when quotes are current, revisions that are accompanied by trades carry new information. We provide evidence that contracts that are thinly traded may possess liquidity attributes as long as their price quotes remain current. © 2003 Wiley Periodicals, Inc. Jrl Fut Mark 23:455–486, 2003 相似文献
998.
Jin E. Zhang 《期货市场杂志》2003,23(6):535-560
This article explores the price of continuously sampled Asian options. For geometric Asian options, we present pricing formulas for both backward‐starting and forward‐starting cases. For arithmetic Asian options, we demonstrate that the governing partial differential equation (PDE) cannot be transformed into a heat equation with constant coefficients; therefore, these options do not have a closed‐form solution of the Black–Scholes type, that is, the solution is not given in terms of the cumulative normal distribution function. We then solve the PDE with a perturbation method and obtain an analytical solution in a series form. Numerical results show that as compared with Zhang's ( 2001 ) highly accurate numerical results, the series converges very quickly and gives a good approximate value that is more accurate than any other approximate method in the literature, at least for the options tested in this article. Graphical results determine that the solution converges globally very quickly especially near the origin, which is the area in which most of the traded Asian options fall. © 2003 Wiley Periodicals, Inc. Jrl Fut Mark 23:535–560, 2003 相似文献
999.
This article provides empirical evidence on the intraday relation between spot volatility and trading volume in the Spanish stock index futures market. GARCH methodology is used to estimate spot volatility. We analyze the potential relation between spot and futures trading volume and spot volatility by estimating the corresponding conditional density functions as proposed in Quah (1997). Our results reveal no significant link between those variables. Similar findings arise when expected and unexpected volume is considered. Our results suggest that derivative market is not a force behind episodes of significant spot jump volatility. © 2003 Wiley Periodicals, Inc. Jrl Fut Mark 23:841–858, 2003 相似文献
1000.
Unlike the traditional futures contract risk‐based approach to margining, new security futures contracts are margined under a strategy‐based margining system similar to that which applies in the equity options markets. As a result, these new margin requirements are potentially much less sensitive to changes in market conditions. This article performs a simulation to evaluate whether these alternative margining methodologies can be expected to produce comparable outcomes. The analysis suggests that a 1‐day settlement period will likely lead to collection of customer margins that are virtually always greater than that which its traditional risk‐based counterpart would require. A 4‐day settlement period would lead to margin requirements that both significantly under‐ and overmargin relative to a comparable risk‐based system. This study argues that exchanges may approach the preferred probability of customer exhaustion by managing margin settlement intervals. Thus, the new strategy‐based rules, in and of themselves, will not necessarily inhibit new security futures trading activity. © 2003 Wiley Periodicals, Inc. Jrl Fut Mark 23:989–1002, 2003 相似文献