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981.
We study the asymptotic behavior of the ruin probabilities in the renewal risk model, in which the insurance company is allowed to invest a constant fraction of its wealth in a stock market which is described by a geometric Brownian motion and the remaining wealth in a bond with nonnegative interest force. We give the expression of the wealth process by the Itô formula, and finally we derive the asymptotic behavior of finite-time and infinite-time ruin probabilities in the presence of pairwise quasi-asymptotically independent claims with dominant varying tails for this model. In the particular case of compound Poisson model, explicit asymptotic expressions for the ruin probabilities are given with tails of regular variation, where the relation of the infinite-time ruin probability is the same as Gaier and Grandits (2004). For this case, we give some numerical results to assess the qualities of the asymptotic relations. 相似文献
982.
Social Indicators Research - It is generally agreed that decentralized decision-making is conducive to the efficient allocation of resources, but detrimental to the equitable redistribution of... 相似文献
983.
Diagnostic odds ratio is defined as the ratio of the odds of the positivity of a diagnostic test results in the diseased population relative to that in the non-diseased population. It is a function of sensitivity and specificity, which can be seen as an indicator of the diagnostic accuracy for the evaluation of a biomarker/test. The naïve estimator of diagnostic odds ratio fails when either sensitivity or specificity is close to one, which leads the denominator of diagnostic odds ratio equal to zero. We propose several methods to adjust for such situation. Agresti and Coull’s adjustment is a common and straightforward way for extreme binomial proportions. Alternatively, estimation methods based on a more advanced sampling design can be applied, which systematically selects samples from underlying population based on judgment ranks. Under such design, the odds can be estimated by the sum of indicator functions and thus avoid the situation of dividing by zero and provide a valid estimation. The asymptotic mean and variance of the proposed estimators are derived. All methods are readily applied for the confidence interval estimation and hypothesis testing for diagnostic odds ratio. A simulation study is conducted to compare the efficiency of the proposed methods. Finally, the proposed methods are illustrated using a real dataset. 相似文献
984.
985.
包心鉴 《山东理工大学学报(社会科学版)》2001,17(3):5-9
我国新时期经济社会转型,不仅意味着对社会主义市场经济体制的选择和对经济增长的追求,而且内涵着对社会文明尤其是人的现代文明的重铸;社会主义现代文明大厦的建构,不仅要有现代市场经济作为其坚固的基础,而且要有全社会成员文化品位的提升和精神素质的增强作为其不朽的支柱.高度重视转型时期人文精神的建构,既是经济社会转型的重要内容,又是顺利推进经济社会转型的重要保证. 相似文献
986.
The Wilcoxon–Mann–Whitney (WMW) test is a popular rank-based two-sample testing procedure for the strong null hypothesis that the two samples come from the same distribution. A modified WMW test, the Fligner–Policello (FP) test, has been proposed for comparing the medians of two populations. A fact that may be under-appreciated among some practitioners is that the FP test can also be used to test the strong null like the WMW. In this article, we compare the power of the WMW and FP tests for testing the strong null. Our results show that neither test is uniformly better than the other and that there can be substantial differences in power between the two choices. We propose a new, modified WMW test that combines the WMW and FP tests. Monte Carlo studies show that the combined test has good power compared to either the WMW and FP test. We provide a fast implementation of the proposed test in an open-source software. Supplementary materials for this article are available online. 相似文献
987.
用热力学方法研究了塔式太阳能热发电中冷回热再热三级不可逆闭式燃气轮机循环的功率和效率.通过数值分析方法,计算了中冷度、回热度对循环最优功率、最优效率及其中间压比分配的关系.与闭式中冷回热燃气轮机循环的功率和效率比较,最大平均功率、最优功率和最优功率效率都有很大的提高. 相似文献
988.
提高广州制造业的文化元素和科技元素的含量,加强文化创意产业与制造业的融合,不仅是提升广州产业竞争力的良方,也是提升广州整体经济竞争力切实可行的举措. 相似文献
989.
Zhang Yuansheng Song Tianjian Jin Qiongyu Huang Yikai Tang Xiaoming Sun Xiaohang Liu Fangming Zhang Zhenhuan Bao Weidong 《Urban Ecosystems》2020,23(1):147-157
Urban Ecosystems - Invasive alien species pose a serious threat to native biodiversity and the ecosystem structure through predation or competition, and this threat is especially severe in China.... 相似文献
990.
新时期党的统一战线的本质,是坚持大团结、大联合,最广泛、最充分地调动一切积极因素,团结一切可以团结的力量,为实现党和国家的宏伟目标而奋斗。本文从坚持马克思主义人本观、民本观、劳动观、财富观、人才观等新的视域,深入阐述了如何发挥统一战线的凝聚共识、团结爱国、整合力量、创造财富、聚集人才等强大功能。 相似文献