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901.
Estimation of the population average by means of a conditional strategy has been considered e.g. in [2–6,9] and [10]. Let us assume that the sampling design depends on a function of an auxiliary variable called an auxiliary statistic like: the sample mean or the sample variance. Under the conditional versions of these designs several estimators of the population mean are considered: the Horvitz-Thompson statistic, ratio and regression type estimators. The unbiasedness and accuracy of the strategies are considered. The empirical example of the accuracy comparisons of strategies is developed. The conditional strategies could improve the accuracy of estimation and protect it against outliers observations.  相似文献   
902.
An algorithmic method is described for the construction of optimal incomplete block designs when a known correlation structure is assumed for observations from plots in the same block. The method is applicable to a wide class of designs and correlation structures. Some examples are given to illustrate the procedure.  相似文献   
903.
In this paper, the spherical distribution is generalized to the Lp-norm spherical distribution, S(n, p), through the stochastic representation. Then the form of its p.d.f. characterizing the S(n, p) distribution is derived. Marginal, conditional distributions and the moments of S(n, p) distribution are obtained. The order statistics and the invariance property of S(n,p) distribution are also investigated.  相似文献   
904.
The joint distribution of (X,Y) is determined if the conditional expectation E {g(X)|Y = y} is given and the conditional distribution of Y|(X = x) is a conditional power series distribution, where g(·) is a function satisfying some minor conditions.  相似文献   
905.
The use of maximum-likelihood estimation as discussed by Sprott and Viveros (1984) is extended to include the log F distribution to accommodate skewness. The role played by linear pivotals in relation to likelihood and efficiency is discussed. Normal, t, and log F likelihoods are defined and used to generate possible normal, t, and log F linear pivotal quantities. The results are applied to the location-scale family, where exact results are available to assess the numerical accuracy of the proposed procedure. Refinements using saddlepoint approximations are obtained.  相似文献   
906.
A simple model for a stationary sequence of dependent integer-valued random variables {Xn} is given. The sequence to be called integer-valued moving average (INMA) process, is taken as the “survivals” of i.i.d. non-negative integervalued random variables. It is argued that the model’s structure reflects to some extent the mechanism generating real life data for many counting process and consequently it is useful for modelling such processes. Various properties for the special case in which {Xn} is Poisson INMA (1) process, such as the joint distribution, regression, time reversibility, along with the conditional and partial correlations, are discussed in details. Extension of the INMA of first order to higher order moving average is considered.  相似文献   
907.
针对矩阵风险,给出了矩阵估计量的多种优良性准则.在这些准则下,得到了带有线性约束的多元回归系数的线性估计是可容许的充要条件,进而由于不同的线性约束所引起的可容许的估计类的不同,我们得到了不同的估计类之间的一种刻划。  相似文献   
908.
Conditions on the hazard functions under the usual log-rank test remains locally optimal for the Cox regression model under random censoring (withdrawal) are examined. In the light of these, the asymptotic efficiency results pertaining to the Cox partial likelihood statistic and the log-rank statistic are studied.  相似文献   
909.
Let f?n, h denote the kernel density estimate based on a sample of size n drawn from an unknown density f. Using techniques from L2 projection density estimators, the author shows how to construct a data-driven estimator f?n, h which satisfies This paper is inspired by work of Stone (1984), Devroye and Lugosi (1996) and Birge and Massart (1997).  相似文献   
910.
自动驾驶汽车是指在没有驾驶员操作的情形下,能够自主、安全地行驶车辆。对其交通肇事后刑事责任的分析应当区分为纯自动驾驶和有条件自动驾驶两种情形。纯自动驾驶汽车交通肇事后,基于“成本收益”的考量,不应当由车辆本身作为刑事责任主体,但由于此时的驾驶者相当于乘客的角色,自始不参与车辆操作,故而设计者成为责任主体,对于肇事行为与结果之间的因果关系宜采用“可能性”的概率论。有条件自动驾驶汽车交通肇事后由驾驶者作为主要的责任人,依据“合法则条件说”对肇事结果承担罪责,设计者、生产者或销售者依其预见可能性,在可能的范围内承担产品过失的罪责。  相似文献   
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