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1.
部分线性模型是一类非常重要的半参数回归模型,由于它既含有参数部分又含有非参数部分,与常规的线性模型相比具有更强的适应性和解释能力。文章研究带有局部平稳协变量的固定效应部分线性面板数据模型的统计推断。首先提出一个两阶段估计方法得到模型中未知参数和非参数函数的估计,并证明估计量的渐近性质,然后运用不变原理构造出非参数函数的一致置信带,最后通过数值模拟研究和实例分析验证了该方法的有效性。 相似文献
2.
AbstractThe problem of testing equality of two multivariate normal covariance matrices is considered. Assuming that the incomplete data are of monotone pattern, a quantity similar to the Likelihood Ratio Test Statistic is proposed. A satisfactory approximation to the distribution of the quantity is derived. Hypothesis testing based on the approximate distribution is outlined. The merits of the test are investigated using Monte Carlo simulation. Monte Carlo studies indicate that the test is very satisfactory even for moderately small samples. The proposed methods are illustrated using an example. 相似文献
3.
以风险理论审视非物质文化遗产的现行法律制度,根据风险产生根源不同,非物质文化遗产保护的制度风险会表现为制度运转失灵风险、制度功能偏差风险和公平性缺失风险。化解制度风险,形成制度风险的维度,不可基于同一个标准,而是需要在大的框架之下论及制度风险的法律管控,需要有针对性地创构"建立私权,善用公权"的多元法律控制体系,并在体系内引入技术规制,创设"非物质文化遗产权",推动民间习惯法与法律制度、公法与私法的互动式发展。 相似文献
4.
系统总结了在伸展构造背景下,导致反映构造特征的地层倾角模式复杂化的多种因素。沉积相的不同、岩性变化、井眼状况和测井作业时间等多种因素都可能使地层倾角资料复杂化。进一步指出在拉张盆地中,进行倾角资料的构造解释,必须了解其构造样式的多样性和复杂性,解释存在的多解性。重点解剖了铲式断层在横剖面情况下,对于不同构造位置下的倾角模式。详细分析了一个倾角模式对应多种构造样式的倾角构造解释实例。倾角资料的构造解释应是综合解释,既要综合井筒的相关地质资料,又要综合测井与地质知识,还必须考虑综合地震资料。 相似文献
5.
Random effects regression mixture models are a way to classify longitudinal data (or trajectories) having possibly varying lengths. The mixture structure of the traditional random effects regression mixture model arises through the distribution of the random regression coefficients, which is assumed to be a mixture of multivariate normals. An extension of this standard model is presented that accounts for various levels of heterogeneity among the trajectories, depending on their assumed error structure. A standard likelihood ratio test is presented for testing this error structure assumption. Full details of an expectation-conditional maximization algorithm for maximum likelihood estimation are also presented. This model is used to analyze data from an infant habituation experiment, where it is desirable to assess whether infants comprise different populations in terms of their habituation time. 相似文献
6.
Catastrophic events, such as floods, earthquakes, hurricanes, and tsunamis, are rare, yet the cumulative risk of each event occurring at least once over an extended time period can be substantial. In this work, we assess the perception of cumulative flood risks, how those perceptions affect the choice of insurance, and whether perceptions and choices are influenced by cumulative risk information. We find that participants' cumulative risk judgments are well represented by a bimodal distribution, with a group that severely underestimates the risk and a group that moderately overestimates it. Individuals who underestimate cumulative risks make more risk‐seeking choices compared to those who overestimate cumulative risks. Providing explicit cumulative risk information for relevant time periods, as opposed to annual probabilities, is an inexpensive and effective way to improve both the perception of cumulative risk and the choices people make to protect against that risk. 相似文献
7.
Mihyun Kim 《Statistics》2019,53(4):699-720
Functional principal component scores are commonly used to reduce mathematically infinitely dimensional functional data to finite dimensional vectors. In certain applications, most notably in finance, these scores exhibit tail behaviour consistent with the assumption of regular variation. Knowledge of the index of the regular variation, α, is needed to apply methods of extreme value theory. The most commonly used method of the estimation of α is the Hill estimator. We derive conditions under which the Hill estimator computed from the sample scores is consistent for the tail index of the unobservable population scores. 相似文献
8.
在零售4.0时代,渠道的多样化不仅丰富了数据源,还能迅速生成大量数据,需要通过分析大数据,为决策提取有意义的信息,通过分析先行发货的重要性,提出了一种基于遗传算法(GA)的优化模型,预测顾客何时购买,然后在顾客线下单前将产品运送到距顾客最近的配送中心,解决先行发货中存在的问题。研究认为,需要先部署云计算来存储所有渠道生成的大数据,再应用基于集群的关联规则挖掘研究顾客的购买行为,根据“如果-那么”预测规则预测未来的采购情况,最后利用修正的遗传算法生成最优的先行发货计划;这种遗传算法考虑了其在运输成本和运输距离之外,还有预测规则的置信度,利用大量的数值实验权衡了先行发货中的不同因素,验证了模型的最优可靠性 相似文献
9.
罗勇 《重庆大学学报(社会科学版)》2020,26(2):153-162
数字货币,是一种具有财产性价值属性的电磁记录型数据。数字货币在其依存的区块链体系中所彰显的与不特定者之间的支付对价性、与法定货币之间的互换性、使用电子信息处理系统进行转移的在线转移性等特点,得以从数据说的角度,将其作为一种数据性财产权在现行法律框架内对其私法性质进行讨论。有鉴于我国民法总则已将数据纳入保护客体的范畴,数字货币作为数据之一种,理应成为一种新型法律客体,在得到法律理论支撑的基础上获得保护。 相似文献
10.
Politics and Scientific Expertise: Scientists, Risk Perception, and Nuclear Waste Policy 总被引:2,自引:0,他引:2
To study the homogeneity and influences on scientists'perspectives of environmental risks, we have examined similarities and differences in risk perceptions, particularly regarding nuclear wastes, and policy preferences among 1011 scientists and engineers. We found significant differences ( p 0.05)in the patterns of beliefs among scientists from different fields of research. In contrast to physicists, chemists, and engineers, life scientists tend to: (a)perceive the greatest risks from nuclear energy and nuclear waste management; (b)perceive higher levels of overall environmental risk; (c)strongly oppose imposing risks on unconsenting individuals; and (d)prefer stronger requirements for environmental management. On some issues related to priorities among public problems and calls for government action, there are significant variations among life scientists or physical scientists. We also found that–independently of field of research–perceptions of risk and its correlates are significantly associated with the type of institution in which the scientist is employed. Scientists in universities or state and local governments tend to see the risks of nuclear energy and wastes as greater than scientists who work as business consultants, for federal organizations, or for private research laboratories. Significant differences also are found in priority given to environmental risks, the perceived proximity of environmental disaster, willingness to impose risks on an unconsenting population, and the necessity of accepting risks and sacrifices. 相似文献