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41.
We examine the presence or absence of asymmetric volatility in the exchange rates of Australian dollar (AUD), Euro (EUR), British pound (GBP) and Japanese yen (JPY), all against US dollar. Our investigation is based on a variant of the heterogeneous autoregressive realized volatility model, using daily realized variance and return series from 1996 to 2004. We find that a depreciation against USD leads to significantly greater volatility than an appreciation for AUD and GBP, whereas the opposite is true for JPY. Relative to volatility on days following a positive one-standard-deviation return, volatility on days following a negative one-standard-deviation return is higher by 6.6% for AUD, 6.1% for GBP, and 21.2% for JPY. The realized volatility of EUR appears to be symmetric. These results are robust to the removal of jump component from realized volatility and the sub-samplings defined by structural-changes. The asymmetry in AUD, GBP and JPY appears to be embedded in the continuous component of realized volatility rather than the jump component.  相似文献   
42.
基于引力模型的中美农产品贸易边境效应研究   总被引:1,自引:0,他引:1  
针对中美两国在农产品贸易上的新变化,应用引力模型的派生模型——边境效应引力模型对中美两国农产品贸易的流量和流向进行理论和实证研究。首先介绍了边境效应引力模型基本模型的推导过程,并引入了调整模型。然后采用1987至2005年其中5年的截面数据进行计算,结果发现:中美农产品贸易的边境效应显著存在,且呈逐年下降趋势;两国之间的农产品贸易边境效应存在流向和区域上的差异;距离的平方并不影响模型的可靠性。  相似文献   
43.
We develop a model explaining the consolidation patterns in the agricultural biotechnology industry. Among different consolidation and cooperation mechanisms, we consider collaborative and licensing agreements, joint ventures, acquisitions, and exchanges of ownership and spin-offs. The key results derive from the benefits of coordinated actions, distinction between transferable and nontransferable payoffs, the substitutability, complementarity, and the importance of the managers' noncontractible investments, and access and expansion of markets. Results from the model are used to examine the cooperation and consolidation activities for four major players in the agricultural biotechnology industry, DuPont , Dow Chemical , Monsanto , and Novartis .  相似文献   
44.
隋唐五代时期园艺作物的培育与引进   总被引:1,自引:0,他引:1  
魏露苓 《中国农史》2003,22(4):18-23
隋唐五代时期是我国园艺业发展史上的重要时期。多种园艺作物培育成功并有为数不少的域外作物引进中土。这些新品种的花果、蔬菜、香料等,为我国园艺业增添了新的内容,丰富了人民生活。有的作物后来传到国外,为世界园艺提供了宝贵的种质资源。培育与引进的成功,则是与隋唐五代时期经济发展、气候条件适宜以及园艺技术提高等因素紧密相关的。  相似文献   
45.
邱丽萍 《价值工程》2004,23(4):76-77
随着知识经济的日益发展,尤其是我国改企建制工作的广泛推行和进一步深化,勘察设计企业为了能更好地应对市场竞争的挑战,其日常运作的各项工作就需要有所改进。而作为企业管理的核心,财务管理则需要密切配合企业改制工作的整体部署,进行相应的创新。本文结合勘察设计企业的实际情况,谈谈实现财务管理创新的几点思路。  相似文献   
46.
The purpose of this article is to use Albert Hirschman's Exit, Voice, and Loyalty framework to analyze the extent to which corporate employees are merely attached to the firm rather than committed. A model of managerial loyalty is developed where loyalty is defined as the percentage pay increase that an employee would require to leave the current firm for alternative employment. Independent variables in the model include barriers to exit and voice. This model was tested on three data sets from North American airlines. This model received empirical support during a stable environment but was not strongly supported during a more turbulent environment. Implications of the results are discussed.  相似文献   
47.
This paper evaluates the performance of glamour and value strategies and tests the extrapolation model for the Japanese equity market. In general, value stocks outperform glamour stocks by between 6 and 12 percent per annum for the five years after portfolio formation. Evidence from past, future and expected growth provides strong support for the story developed in Lakonishok, Shleifer and Vishny (1994). It is difficult to attribute the value premia to the difference, if any, in risk factors. In addition, the book-to-market premium is much closer to an arbitrage opportunity than the size premium.  相似文献   
48.
This paper employed eleven data series which consist of stocks, bonds, bills, equity premiums, term premiums, and various default premiums to investigate whether January seasonality reported in existing literature is robust across different states of the economy as this has important trading implications. For the periods 1926–1990, small stocks, small stock premiums, low grade bonds, and default premiums (spread between high grade, low grade and government bonds) reveal January seasonality and that the seasonality is robust across different states of the economy except for low grade bond returns and default premiums. January seasonality for low grade bond returns and low grade bond default premiums are primarily driven by results found during periods of economic expansion. Overall, January seasonality is more evident during the economic expansion periods although the magnitude of default premiums is larger during periods of economic contraction. Furthermore, prior findings of strong summer equity returns are primarily driven by the results found during the periods of economic contraction. It is also found that equity returns are generally higher during periods of economic expansion.  相似文献   
49.
在当今世界,俄罗斯在解决国际重大争端,处理全球重大事务等方面具有不可或缺、不可替代的重要地位和作用.因此,研究普京的内政外交新动向意义重大.在内政方面,普京正在全力实施以能源、武器和原材料生产为核心的中长期经济振兴计划,提出了10年内翻番的目标.在对外事务中的布局层次是--独联体是重中之重,欧洲及美国是首要,亚太一些周边大国是关键,东欧、中东、非洲和拉美不可忽视.  相似文献   
50.
纯氧曝气的研究进展   总被引:9,自引:0,他引:9  
介绍了纯氧曝气的生化机理、应用领域、供氧方式、污泥性能等以及它与普通空气曝气相比在技术、经济方面显示出的优越性。随着纯氧曝气的发展和国家新标准增加了脱氮除磷方面的排放要求,使得纯氧曝气在城市污水处理老厂的改造和新厂的建设中具有很好的前昔。  相似文献   
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