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41.
In this paper, we consider the laws of large numbers for NSD random variables satisfying Pareto-type distributions with infinite means. Based on the Pareto-Zipf distributions, some weak laws of large numbers for weighted sums of NSD random variables are obtained. Meanwhile, we show that a weak law for Pareto-Zipf distributions cannot be extended to a strong law. Furthermore, based on the two tailed Pareto distribution, a strong law of large numbers for weighed NSD random variables is presented. Our results extend the corresponding earlier ones. 相似文献
42.
Let X = {X1, X2, …} be a sequence of independent but not necessarily identically distributed random variables, and let η be a counting random variable independent of X. Consider randomly stopped sum Sη = ∑ηk = 1Xk and random maximum S(η) ? max?{S0, …, Sη}. Assuming that each Xk belongs to the class of consistently varying distributions, on the basis of the well-known precise large deviation principles, we prove that the distributions of Sη and S(η) belong to the same class under some mild conditions. Our approach is new and the obtained results are further studies of Kizinevi?, Sprindys, and ?iaulys (2016) and Andrulyt?, Manstavi?ius, and ?iaulys (2017). 相似文献
43.
近年来,由于中美经济联系日趋紧密,中美股票市场大幅波动的互激效应明显增强。本文考虑中美股市时差和法定节假日差异等因素,运用标值Hawkes过程对2006-2017年CSI300和S&P500大幅波动收益率数据进行建模,结果表明:(1)中美股市大幅波动互激效应存在不对称性,美股市场大幅波动对中国股市的互激效应更强;(2)中美股市大幅波动的幅度对互激效应不存在显著影响;(3)中美股票市场对于大幅波动互激效应的消化速度存在差异,中国股票市场消化美股大幅波动互激效应的速度较快。本研究对金融市场监管者和投资者均有一定意义。 相似文献
44.
本文结合我国上市公司所面临的内部治理机制特点及外部治理环境,从大股东行为的视角对公司现金持有量的影响因素进行实证分析。在加入年度控制变量、行业控制变量和公司财务特征控制变量后,对三项反映大股东行为特征的因素,即大股东持股比例、大股东属性和制度环境因素对公司现金持有量的影响进行了检验。结果表明,第一大股东持股比例较高的公司持有较多的现金,大股东的高持股比例是其占用企业资金侵占中小股东利益的基础。与国有企业相比,民营企业因遭受较强的外部融资约束而持有较高水平的现金。此外,制度环境的发展程度与公司现金持有水平正相关,表明制度环境较好地区的公司持有较多的现金。 相似文献
45.
An Examination of the Dual Model of Perfectionism and Adolescent Athlete Burnout: A Short-Term Longitudinal Research 总被引:1,自引:0,他引:1
The dual model of perfectionism (Slade and Owens, Behav Modificat 22(3):372–390, 1998) is adopted to examine the influence
of adaptive and maladaptive perfectionism on adolescent athlete burnout in Taiwan. Participants were 188 high school adolescent
student-athletes (M = 16.48, SD = .59). They were administered the Multidimensional Inventory of Perfectionism in Sport (Stoeber et al., Pers Individ Dif
43(1):131–141, 2007) and the Chinese Athlete Burnout Questionnaire (ABQ) (Lu et al., Phys Educ J 39(3):83–94, 2006). A field
longitudinal design was used. In cross-sectional analyses, hierarchical multiple regressions indicated that adaptive perfectionism
negatively predicted athlete burnout while maladaptive perfectionism had an inverse relationship with burnout. However, after
controlling for the initial scores of burnout, neither adaptive nor maladaptive perfectionism significantly predicted athlete
burnout after a three month interval. Possible mechanisms of this relation, limitations, and practical implications are discussed. 相似文献
46.
47.
In this paper, we investigate the precise large deviations for sums of φ-mixing and UND random variables with long-tailed distributions. The asymptotic relations for non random sum and random sum of random variables with long-tailed distributions are obtained. 相似文献
48.
The aim of this paper is to propose methods of detecting change in the coefficients of a multinomial logistic regression model for categorical time series offline. The alternatives to the null hypothesis of stationarity can be either the hypothesis that it is not true, or that there is a temporary change in the sequence. We use the efficient score vector of the partial likelihood function. This has several advantages. First, the alternative value of the parameter does not have to be estimated; hence, we have a procedure that has a simple structure with only one parameter estimation using all available observations. This is in contrast with the generalized likelihood ratio-based change point tests. The efficient score vector is used in various ways. As a vector, its components correspond to the different components of the multinomial logistic regression model’s parameter vector. Using its quadratic form a test can be defined, where the presence of a change in any or all parameters is tested for. If there are too many parameters one can test for any subset while treating the rest as nuisance parameters. Our motivating example is a DNA sequence of four categories, and our test result shows that in the published data the distribution of the four categories is not stationary. 相似文献
49.
50.
西部大开发所面临的环境代价问题及对策 总被引:2,自引:0,他引:2
我国西部地区生态环境脆弱,近年来由于经济发展过程中的一些不正确行为,使得西部地区生态环境问题日趋严重。实施西部大开发必然要面临着环境代价这一问题,为了有效地控制环境代价问题,必须一靠政府有效干预,正确引导;二靠加强技术进步转变资源配置方式;此外,还要牢固地树立“可持续发展”观念。 相似文献