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61.
浅析中国土族人口分布格局及其社会发展 总被引:2,自引:0,他引:2
人口分布格局,既是人在空间分布上呈现出来的地理状态,又是许多附着于分布环境上的社会人文变量的外在表现,因此对其进行研究具有探索自然和认识社会的双重意义。本文就中国土族人口的分布格局进行探讨,从历史和现实两方面分析了形成这种分布的原因,并在此基础上探讨了与人口分布格局密切相关的人口城市化、人口流动、人口素质提高、区域经济发展等社会热点问题,以期为政府政策的制定提供可靠的依据。 相似文献
62.
西部人口与可持续发展 总被引:1,自引:0,他引:1
可持续发展要求有良好的人口环境。人口是西部可持续发展的首要问题。在西部发展中 ,制定积极的人口政策 ,控制人口、提高人口素质 ,为西部可持续发展创造良好的人口环境 相似文献
63.
This paper investigates the effect of cognitive abilities on financial behavior among older adults. Using the U.S. Health and Retirement Study, I find that cognitive abilities significantly affect financial behavior through two channels: ability and self-efficacy. People with higher cognition scores achieve better financial outcomes. This positive association is especially strong in tasks having high demand of cognitive abilities, which confirms the ability channel of the cognitive ability effect. In addition, there is evidence for the self-efficacy channel as a secondary source of cognitive influence. Lower cognitive abilities decrease people’s sense of self-efficacy, which, in turn, significantly decreases financial management efficiency. The findings have important policy implications, specifically that more effort is needed to assist the growing older population through the cognitive aging process and that noncognitive skills, as a secondary source of influence, also warrant attention. 相似文献
64.
Bridget M. Nugent Rajanikanth Madabushi Barbara Buch Vasum Peiris Victor Crentsil Virginia M. Miller Jonca Bull Marjorie R. Jenkins 《Pharmaceutical statistics》2021,20(5):929-938
Differences in patient characteristics, including age, sex, and race influence the safety and effectiveness of drugs, biologic products, and medical devices. Here we provide a summary of the topics discussed during the opening panel at the 2018 Johns Hopkins Center for Excellence in Regulatory Science and Innovation symposium on Assessing and Communicating Heterogeneity of Treatment Effects for Patient Subpopulations: Challenges and Opportunities. The goal of this session was to provide a brief overview of FDA-regulated therapeutics, including drugs, biologics and medical devices, and some of the major sources of heterogeneity of treatment effects (HTE) related to patient demographics, such as age, sex and race. The panel discussed the US Food and Drug Administration's role in reviewing and regulating drugs, devices, and biologic products and the challenges associated with ensuring that diverse patient populations benefit from these therapeutics. Ultimately, ensuring diverse demographic inclusion in clinical trials, and designing basic and clinical research studies to account for the intended patient population's age, sex, race, and genetic factors among other characteristics, will lead to better, safer therapies for diverse patient populations. 相似文献
65.
66.
长春市城乡人口老龄化与老年社会保障问题研究 总被引:1,自引:1,他引:1
依据国际人口年龄结构类型判断标准,目前长春市正从初步人口老龄化向全面老年型转变。长春市人口老龄化的特征是:人口老龄化速度快,未来人口老龄化形势严峻;老龄化程度在吉林省内属于较高水平;人口老龄化超前于社会经济发展水平;高龄老年人口增长迅速。人口老龄化问题对长春市社会经济发展,以及全面建设小康社会的影响作用日益显著。通过对长春市老年社会福利保障、城乡养老保险制度改革、特殊老年群体问题的深入分析,提出健全与完善长春市养老保障体制,解决老年社会保障问题的对策建议。 相似文献
67.
The Best Linear Unbiased Predictor (BLUP) in mixed models is a function of the variance components and they are estimated using maximum likelihood (ML) or restricted ML methods. Nonconvergence of BLUP would occur due to a drawback of the standard likelihood-based approaches. In such situations, ML and REML either do not provide any BLUPs or all become equal. To overcome this drawback, we provide a generalized estimate (GE) of BLUP that does not suffer from the problem of negative or zero variance components, and compare its performance against the ML and REML estimates of BLUP. Simulated and published data are used to compare BLUP. 相似文献
68.
Confidence intervals for parameters of distributions with discrete sample spaces will be less conservative (i.e. have smaller coverage probabilities that are closer to the nominal level) when defined by inverting a test that does not require equal probability in each tail. However, the P‐value obtained from such tests can exhibit undesirable properties, which in turn result in undesirable properties in the associated confidence intervals. We illustrate these difficulties using P‐values for binomial proportions and the difference between binomial proportions. 相似文献
69.
The authors study the asymptotic behaviour of the likelihood ratio statistic for testing homogeneity in the finite mixture models of a general parametric distribution family. They prove that the limiting distribution of this statistic is the squared supremum of a truncated standard Gaussian process. The autocorrelation function of the Gaussian process is explicitly presented. A re‐sampling procedure is recommended to obtain the asymptotic p‐value. Three kernel functions, normal, binomial and Poisson, are used in a simulation study which illustrates the procedure. 相似文献
70.
Hu Yang 《统计学通讯:理论与方法》2013,42(22):4078-4085
In this article, we first present four matrix norm Kantorovich-type inequalities involving non negative definite matrix. Then, based on these inequalities, we propose four new efficiency criteria and present their lower bounds to make efficiency comparisons between the ordinary least squares estimator and the best linear unbiased estimator in a singular linear model. 相似文献