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101.
In this study, we propose nonparametric tests using the several quantile statistics simultaneously for the right censored data. First of all, we consider statistics of the quadratic form with estimated covariance matrices. Then we derive the limiting distribution using the large sample approximation theory. Also we consider different forms of statistics such as the maximal and summing types with their limiting distributions. Then we illustrate our procedure with examples and compare performance among tests with empirical powers through a simulation study. Also we comment briefly on some interesting features including re-sampling methods as concluding remarks. Finally in Appendices, we provide proofs for the theoretic results needed for the derivation of the limiting distributions of the proposed test statistics.  相似文献   
102.
In this article, we first establish a theorem that represents the price of an Asian option in terms of standard European options with a shorter term and different strikes. Then using Gauss–Hermite numerical integration, we discretize our theorem so as to use Monte Carlo simulation to examine the error of the static hedging under the Black–Scholes model and the Merton jump-diffusion model. For ease of comparison, we also provide the error of the dynamic hedging. The numerical results show that the static hedging strategy performs better than the dynamic one under both models.  相似文献   
103.
赵会荣 《北方论丛》2022,(1):53-62+172
新冠肺炎疫情对白俄罗斯经济、社会和政治造成巨大冲击,暴露并加剧了白俄罗斯国家和社会治理领域存在的问题。在疫情背景下,白俄罗斯第六届总统选举触发政治危机。卢卡申科政府通过采取有效措施应对使紧张局势逐渐趋于缓和,国内恢复正常秩序,内外政策随之调整,对内宣布启动修宪,对外加强非西方外交,尤其加强与俄罗斯的联盟关系。疫情发生以来,中国与白俄罗斯开展了行之有效的合作,对于促进白俄罗斯稳定与发展发挥了积极的作用,并为后疫情时代构建中白卫生健康命运共同体奠定了良好基础。  相似文献   
104.
105.
运用ARFIMA-FIAPARCH-skst模型对沪深300指数和香港恒生指数建立收益-波动模型, 然后结合估计的参数对模型进行修正以确立最终模型, 排除金融市场典型事实对相依关系的影响, 进而运用由Clayton、Frank和Gumbel组成的混合copula模型对相依结构进行建模。研究结果表明:内地市场和香港市场均未观察到显著的杠杆效应;由Clayton、Frank和Gumbel组成的混合Copula模型能够准确地描述两个市场之间的相依结构, 且两个市场下尾相依关系要强于上尾的相依关系, 通过动态混合copula也验证了这一明显的非对称关系。  相似文献   
106.
This paper contrasts and compares the institutional framework for fatherhood and father involvement and the survey evidence relating to fathers’ contribution to childcare and domestic work in the two countries. It shows that while men's contribution to such activities appears to be increasing in both France and the UK, change is slow and father involvement does not necessarily seem to correlate directly either with patterns of female labour force participation or with the support offered by the institutional framework. The authors explore the theoretical frameworks most appropriate for explaining their findings and situate them primarily in terms of Pfau-Effinger's theorization of the gender arrangement (1998, 2002, 2004). The authors conclude that while change in father involvement is slow, the introduction of statutory and organizational work–life balance measures which alter the gender order open up opportunities for negotiated change in the division of the labour in the home.  相似文献   
107.
Summary. Many biomedical studies involve the analysis of multiple events. The dependence between the times to these end points is often of scientific interest. We investigate a situation when one end point is subject to censoring by the other. The model assumptions of Day and co-workers and Fine and co-workers are extended to more general structures where the level of association may vary with time. Two types of estimating function are proposed. Asymptotic properties of the proposed estimators are derived. Their finite sample performance is studied via simulations. The inference procedures are applied to two real data sets for illustration.  相似文献   
108.
Public–private partnerships (PPPs) are perhaps the key emergent theme in the delivery of what the socio-economic literature terms global public goods. In light of the problems relating to the distribution of health services and products in developing countries, partnerships between public and private institutions are often proposed as an innovative mechanism to reconnect and reorient supply and demand. In this area, the International Aids Vaccine Initiative (IAVI), which is driving the development of candidate HIV/AIDS vaccines through injections of capital into the research process, represents a significant case study. IAVI seeks to form partnerships between key public and private interests committing them to sharing the risks, costs and benefits of research into an effective and affordable vaccine against HIV. Our empirical work covers partnerships based in several countries including Kenya, Uganda, Rwanda and India. Our early findings highlight IAVI's ability as a learning institution as it adapts its institutional arrangements to various local contexts. An offshoot of this appears to be the building of real local capacity.  相似文献   
109.
A pressing need in the area of food safety is a tool for making overall, macro-judgments about which risks should be given priority for management. Governments often seek to base this prioritization on public health impacts only to find that other considerations also influence the prioritization process. A multi-factorial approach formally recognizes that public health, market-level impacts, consumer risk preferences and acceptance, and the social sensitivity of particular risks all play a role in prioritization. It also provides decision-makers with a variety of information outputs that allow risk prioritization to be considered along different dimensions. Macro-level prioritization of risks based on multiple factors is an important expanded use of cost–benefit analysis to manage risk.  相似文献   
110.
Rivest Wells (2001) showed that in situations where the dependence between a lifetime and a censoring variable can be modeled by a given Archimedean copula, the copula‐graphic estimator of Zheng Klein (1995) has an explicit form. The authors extend this work to the fixed design regression case. They show that the copula‐graphic estimator then has an asymptotic representation and a Gaussian limit. They also assess the influence of a misspecified copula function on the performance of the estimator. Their developments are illustrated with data on the survival of the Atlantic halibut.  相似文献   
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