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311.
This note consists of two parts . In the first part, we provide a pedagogic review on the multivariate generalized hyperbolic (MGH) distribution. We show that this probability family is close under margining, conditioning, and linear transforms; however, such property does not hold for its subclasses. In the second part, we obtain the Stein-type inequality in the context of MGH distribution. Moreover, we apply the Stein-type inequality to prove a lower bound for Var[h(X)]. Particularly, we present examples when X belongs to some well-known subclasses in MGH family.  相似文献   
312.
We propose some Stein-rule combination forecasting methods that are designed to ameliorate the estimation risk inherent in making operational the variance–covariance method for constructing combination weights. By Monte Carlo simulation, it is shown that this amelioration can be substantial in many cases. Moreover, generalized Stein-rule combinations are proposed that offer the user the opportunity to enhance combination forecasting performance when shrinking the feasible variance–covariance weights toward a fortuitous shrinkage point. In an empirical exercise, the proposed Stein-rule combinations performed well relative to competing combination methods.  相似文献   
313.
基于其天人合一的自然观,孔子提出了“仁爱、民本、求利循义”,“因民之所利而利之”等意深境远的价值论根据和“为学、中庸、仁知统一”等贯通古今的方法论遵循,这不仅为古代中国的科技发展,而且也为人类技术的未来发展提供了坚实的世界观基础、正确的价值观导向和科学的方法论指导。  相似文献   
314.
语言静态是相对的,动态是绝对的。当下“猪流感”到“甲型H1N1流感”术语变更的实际情形表明,语言生成会经过“基础、修正、生成”的直线过程,经受从言语到语言的心理认知过程。  相似文献   
315.
应急物流的高效运作能够降低突发事件造成的危害,因而得到了理论界的广泛关注。鉴于甲流感疫情下我国防控工作的严峻性,在指出我国现阶段应急物流中存在的问题并提出相关建议后,构建了疫情防控工作下的应急物流体系,并对每个流程做了详细阐述。  相似文献   
316.
This paper considers regression analysis of multivariate panel count data with the focus on variable selection and estimation of significant covariate effects. For the problem, we adopt the penalized estimating equation approach with a focus on the use of the seamless‐$L_0$ penalty. The proposed approach selects variables and estimates regression coefficients simultaneously and the asymptotic properties of the resulting estimates are established. The procedure can be easily carried out with the Newton–Raphson algorithm and is evaluated by simulation studies. Also it is applied to a motivating data set arising from a skin cancer study. The Canadian Journal of Statistics 41: 368–385; 2013 © 2013 Statistical Society of Canada  相似文献   
317.
318.
Classes of distribution-free tests are proposed for testing homogeneity against order restricted as well as unrestricted alternatives in randomized block designs with multiple observations per cell. Allowing for different interblock scoring schemes, these tests are constructed based on the method of within block rankings. Asymptotic distributions (cell sizes tending to infinity) of these tests are derived under the assumption of homogeneity. The Pitman asymptotic relative efficiencies relative to the least squares statistics are studied. It is shown that when blocks are governed by different distributions, adaptive choice of scores within each block results in asymptotically more efficient tests as compared with methods that ignore such information. Monte Carlo simulations of selected designs indicate that the method of within block rankings is more power robust with respect to differing block distributions.  相似文献   
319.
Elementary inductive proofs are presented for the binomial approximation to the hypergeometric distribution, the density of an order statistic, and the distribution of when X 1, ···, X n are a sample from N (μ, 1).  相似文献   
320.
In this paper, I study the impact of managers’ affiliations with the Freemasonry on the performances of companies. Using a unique data set of 412 companies quoted on the London Stock Exchange between 1895 and 1902, I find that young and small firms run by Masonic managers exhibited larger leverage ratios. These companies earned higher profits, although the effect is not statistically significant. Large publicly quoted corporations managed by Freemasons instead had lower profits and lower Tobin’s Q. I discuss the issue of the endogeneity of Freemasonry membership, and I use four different approaches to partially address this.  相似文献   
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