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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   
23.
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   
24.
Asian‐Basket‐type moving‐window contracts are an increasingly used risk‐management tool in the North American hog sector. The moving‐window contract is decomposed into a portfolio of a long Asian‐Basket put and a short Asian‐Basket call option. A projected break‐even price is used to determine the floor price, and then Monte Carlo simulation methods are used to price both a moving‐ and a fixed‐window contract. These methods provide unbiased pricing of fixed‐ and moving‐window hog‐finishing contracts of 1‐year duration. © 2003 Wiley Periodicals, Inc. Jrl Fut Mark 23:1047–1073, 2003  相似文献   
25.
An Internet presence is a critical early component in the process of building towards a fully operational and unified e‐commerce strategy. E‐commerce has significantly impacted logistics/supply chain strategies and the development and implementation of a website have become key issues for many firms within the transportation industry. This study provides an overview of website content within the motor carrier industry. Content analysis was used to assess the site design, informational content, and the interactive content of 152 motor carrier websites, and to compare the features offered on the Top 100 motor carrier firm websites with those offered on the sites of smaller carrier firms.  相似文献   
26.
This article introduces and explores the concept of brand name imprinting. Brand name imprinting is the process of creating and strengthening the brand name node in the brand memory network through brand name exposure. Brand name imprinting at a time prior to the presentation of specific brand information is posited to improve the retention of that information by strengthening the association between the brand name and brand information. The effect is proposed to be automatic and independent of other known means to strengthen memory associations (e.g., level of attention, cognitive elaboration, stimuli vividness, and stimuli distinctiveness). This research also proposes that brand names with neutral meaning better facilitate the imprinting effect, because they do not carry perceptual baggage that can interfere with the creation of new brand name–information associations. An experiment involving brand name imprinting and the learning of brand information supports these assertions. Implications for communication strategy and brand name selection are discussed. © 2003 Wiley Periodicals, Inc.  相似文献   
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Cash settlement of derivative contracts makes them susceptible to manipulation by traders who expect to close large positions upon final settlement. Cash settlement also increases underlying volatility when hedgers unwind their hedges if they have no incentives to control their trading costs. Limits on the positions that traders can carry into final settlement can be used to mitigate associated economic inefficiencies when surveillance is insufficient. This article develops a model that regulators can use to set these limits that is based upon microstructure theory. The empirical findings indicate that existing position limits are largely inconsistent with those suggested by the model. © 2005 Wiley Periodicals, Inc. Jrl Fut Mark 25:945–965, 2005  相似文献   
29.
"This study surveys the policy issues associated with urbanization following the abolition of the pass laws [in South Africa]. The demographic background is briefly sketched. Using neo-classical analysis as a starting point, particular attention is paid to the present inefficiencies of city form associated with segregation. It is argued that current planning procedures are in danger of perpetuating or even worsening the situation. Obstacles to employment generation are considered and transport, local government and housing issues are discussed. On every front, urbanization policy is unstable and, even in the short term, there will be pressures to change it."  相似文献   
30.
The linkage between development and health is clearly spelt out in the definition of primary health care by the World Health Organisation. There is a widespread and growing disillusionment with the traditional Western approach to health care which fails to meet the real demands of the Third World situation.

This paper looks briefly at conditions in the developing world and the strategy proposed by the W H O to attempt to meet the objective of health for all by the year 2000 and refers to the South African situation.  相似文献   

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