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891.
Abstract

In this paper, we establish the complete convergence and complete integral convergence for arrays of row-wise extended independent random variables under sub-linear expectation space with some conditions. At the same time we extend some complete convergence and complete integral convergence theorems from the classical probability space to the sub-linear expectation space. The results generalize corresponding results obtained by Wu et al. (2017 Zhang, L. X. 2016b. Exponential inequalities under the sub-linear expectations with applications to laws of the iterated logarithm. Science China Mathematics 59 (12):250326. doi: 10.1007/s11425-016-0079-1.[Crossref], [Web of Science ®] [Google Scholar]).  相似文献   
892.
Empirical Bayes (EB) methods are very useful for post selection inference. Following Datta et al. (2002 Datta, G. S., M. Ghosh, D. D. Smith, and P. Lahiri. 2002. On an asymptotic theory of conditional and unconditional coverage probabilities of empirical Bayes confidence intervals. Scandinavian Journal of Statistics 29:13952.[Crossref], [Web of Science ®] [Google Scholar]), we construct EB confidence intervals for the selected population mean. The EB intervals are adjusted to achieve the target coverage probabilities asymptotically up to the second order. Both unconditional coverage probabilities of EB intervals and corresponding probabilities conditional on ancillary statistics are found.  相似文献   
893.
Bayesian statistics offers an alternative to classical (frequentist) statistics. It is distinguished by its use of probability distributions to describe uncertain quantities, which leads to elegant solutions to many difficult statistical problems. Although Bayesian demography, like Bayesian statistics more generally, is around 250?years old, only recently has it begun to flourish. The aim of this paper is to review the achievements of Bayesian demography, address some misconceptions, and make the case for wider use of Bayesian methods in population studies. We focus on three applications: demographic forecasts, limited data, and highly structured or complex models. The key advantages of Bayesian methods are the ability to integrate information from multiple sources and to describe uncertainty coherently. Bayesian methods also allow for including additional (prior) information next to the data sample. As such, Bayesian approaches are complementary to many traditional methods, which can be productively re-expressed in Bayesian terms.  相似文献   
894.
Conditioning Capacities and Choquet Integrals: The Role of Comonotony   总被引:1,自引:0,他引:1  
Chateauneuf  Alain  Kast  Robert  Lapied  André 《Theory and Decision》2001,51(2-4):367-386
Choquet integrals and capacities play a crucial role in modern decision theory. Comonotony is a central concept for these theories because the main property of a Choquet integral is its additivity for comonotone functions. We consider a Choquet integral representation of preferences showing uncertainty aversion (pessimism) and propose axioms on time consistency which yield a candidate for conditional Choquet integrals. An other axiom characterizes the role of comonotony in the use of information. We obtain two conditioning rules for capacities which amount to the well-known Bayes' and Dempster–Schafer's updating rules. We are allowed to interpret both of them as a lack of confidence in information in a dynamic extension of pessimism. This revised version was published online in June 2006 with corrections to the Cover Date.  相似文献   
895.
Decades of rigorous quantitative scholarship have generated a wealth of knowledge regarding the causes and consequences of crossnational variations in social trust. However, while some social science disciplines have made significant contributions to this conversation, others have largely failed to do so. The field of international relations, for example, has lagged behind in producing aggregate-level scholarship on social trust. This is surprising given that (1) trust influences public opinion and thereby the incentive structure for political leaders and (2) many peacebuilding efforts directly target the levels of trust in post-conflict settings. Country-level trust scholarship in international relations and the social sciences more generally is hampered by data scarcity. The main purpose of this article is to present a new publicly available data set on aggregate levels of social trust. Relying on a set of 19 widely accepted correlates, we construct a new cross-sectional measure of the concept that covers all countries from 1946 to 2010. We then perform a series of empirical tests establishing the validity of our measure. Finally, we offer a number of bivariate analyses to demonstrate the broad utility of our new variable for scholars in the social sciences.  相似文献   
896.
A number of researchers have called attention to the lack of information available on transracial adoption at the national level. This project was a concerted effort to identify detailed informational about transracial adoption in the United States from nationally representative data sources. The 2000 U.S. Census and 2008–2012 American Community Survey data were analyzed to identify information about the number of young adoptees adopted transracially in the population, the proportion of transracial adoptions that are international, which racial groups adopt transracially, and which racial groups are transracially adopted in the 21st century.  相似文献   
897.
Swati Agiwal 《Risk analysis》2012,32(8):1309-1325
In the aftermath of 9/11, concern over security increased dramatically in both the public and the private sector. Yet, no clear algorithm exists to inform firms on the amount and the timing of security investments to mitigate the impact of catastrophic risks. The goal of this article is to devise an optimum investment strategy for firms to mitigate exposure to catastrophic risks, focusing on how much to invest and when to invest. The latter question addresses the issue of whether postponing a risk mitigating decision is an optimal strategy or not. Accordingly, we develop and estimate both a one‐period model and a multiperiod model within the framework of extreme value theory (EVT). We calibrate these models using probability measures for catastrophic terrorism risks associated with attacks on the food sector. We then compare our findings with the purchase of catastrophic risk insurance.  相似文献   
898.
Summary Modified formulas for the Wald and Lagrangian multiplier statistics are introduced and considered together with the likelihood ratio statistics for testing a typical null hypothesisH 0 stated in terms of equality constraints. It is demonstrated, subject to known standard regularity conditions, that each of these statistics and the known Wald statistic has the asymptotic chi-square distribution with degrees of freedom equal to the number of equality constraints specified byH 0 whether the information matrix is singular or nonsingular. The results of this paper include a generalization of the results of Sively (1959) concerning the equivalence of the Wald, Lagrange multiplier and likelihood ratio tests to the case of singular information matrices.  相似文献   
899.
针对同时要求布料运动实时性、真实性和稳定性的应用,该文从简化布料运动仿真模型和改进积分方法着手,提供了实时布料运动仿真方法。使用该方法实现的布料仿真系统速度快、稳定性好,且易于实现。  相似文献   
900.
When testing the equality of the means from two independent normally distributed populations given that the variances of the two populations are unknown but assumed equal, the classical Student's two-sample t-test is recommended. If the underlying population distributions are normal with unequal and unknown variances, either Welch's t-statistic or Satterthwaite's approximate F test is suggested. However, Welch's procedure is non-robust under most non-normal distributions. There is a variable tolerance level around the strict assumptions of data independence, homogeneity of variances, and identical and normal distributions. Few textbooks offer alternatives when one or more of the underlying assumptions are not defensible. While there are more than a few non-parametric (rank) procedures that provide alternatives to Student's t-test, we restrict this review to the promising alternatives to Student's two-sample t-test in non-normal models.  相似文献   
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