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31.
In this paper, a nonparametric method for reliability of the stress-strength model is proposed when the dependent stress variable and strength variable are subject to right censoring. The dependence between variables is measured by the common Farlie-Gumbel-Morgenstern copula function and Clayton copula function. Using the empirical process theory, consistency and asymptotic normality of the proposed estimator is established in this paper. The results of numerical simulation show that the proposed method performs well in the case of finite sample. The method proposed in this paper has a wide application prospect in practice.  相似文献   
32.
兰冲锋  吴群英 《数学杂志》2015,35(3):665-671
本文研究了扩展负相依(END)样本最近邻密度估计的强相合性问题.利用END序列的Bernstein型不等式和截尾的方法,获得了END样本最近邻密度估计的强相合速度,推广了NA样本和ND样本最近邻密度估计的相应结果.  相似文献   
33.
We develop in this article an a posteriori error estimator for the P1‐nonconforming finite element approximation, for a diffusion‐reaction equation. We adopt the error in a constitutive law approach in two and three dimensional space, for not necessary piecewise constant data of problems. The efficiency and the reliability of our estimators are proved, neither Helmholtz decomposition of the error nor saturation assumption. The constants are explicitly given, which prove the robustness of these estimators. © 2014 Wiley Periodicals, Inc. Numer Methods Partial Differential Eq 31: 950–976, 2015  相似文献   
34.
部分线性模型中估计的收敛速度   总被引:30,自引:0,他引:30  
高集体  洪圣岩  梁华 《数学学报》1995,38(5):658-669
考虑回归模型(Ⅰ):其中(x_i,t_i)是固定非随机设计点列,x_i=(x_(il),…,x_(ip))'β=(β_1,…,β_p)'(p>1),g是定义在[0,1]上的未知函数,β是未知待估参数,0<t_i<1,e_i是i.i.d.随机误差,且Ee_i=0,Ee=σ ̄2<∞。基于g的估计取一类非参数权估计(包括常见的核估计和近邻估计),我们讨论了β的最小二乘估计及g的估计的最优强弱收敛速度。  相似文献   
35.
Consider the classical nonparametric regression problem yi = f(ti) + ii = 1,...,n where ti = i/n, and i are i.i.d. zero mean normal with variance 2. The aim is to estimate the true function f which is assumed to belong to the smoothness class described by the Besov space B pq q . These are functions belonging to Lp with derivatives up to order s, in Lp sense. The parameter q controls a further finer degree of smoothness. In a Bayesian setting, a prior on B pq q is chosen following Abramovich, Sapatinas and Silverman (1998). We show that the optimal Bayesian estimator of f is then also a.s. in B pq q if the loss function is chosen to be the Besov norm of B pq q . Because it is impossible to compute this optimal Bayesian estimator analytically, we propose a stochastic algorithm based on an approximation of the Bayesian risk and simulated annealing. Some simulations are presented to show that the algorithm performs well and that the new estimator is competitive when compared to the more standard posterior mean.  相似文献   
36.
Let X 1 ,...,X n be a random sample drawn from distribution function F(x) with density function f(x) and suppose we want to estimate X(x). It is already shown that kernel estimator of F(x) is better than usual empirical distribution function in the sense of mean integrated squared error. In this paper we derive integrated squared error of kernel estimator and compare the error with that of the empirical distribution function. It is shown that the superiority of kernel estimators is not necessarily true in the sense of integrated squared error.  相似文献   
37.
RANDOM WEIGHTING APPROXIMATION IN LINEAR REGRESSION MODELS   总被引:1,自引:0,他引:1  
RANDOMWEIGHTINGAPPROXIMATIONINLINEARREGRESSIONMODELSSHIJIAN(DepartmentofProbabilityandStatistics,PekingUniversity,Beijing1008...  相似文献   
38.
Representation theorem and local asymptotic minimax theorem are derived for nonparametric estimators of the distribution function on the basis of randomly truncated data. The convolution-type representation theorem asserts that the limiting process of any regular estimator of the distribution function is at least as dispersed as the limiting process of the product-limit estimator. The theorems are similar to those results for the complete data case due to Beran (1977, Ann. Statist., 5, 400–404) and for the censored data case due to Wellner (1982, Ann. Statist., 10, 595–602). Both likelihood and functional approaches are considered and the proofs rely on the method of Begun et al. (1983, Ann. Statist., 11, 432–452) with slight modifications.Division of Biostatistics, School of Public Health, Columbia Univ.  相似文献   
39.
分位点函数的光滑非参数估计的BAHADUR表示   总被引:1,自引:0,他引:1  
文中对分位函数给出了具有更广泛应用的光滑分位估计,证明了该光滑分位估计的逐点和一致的Bahadur强表示定理;并由此结果推导了估计的重对数律,强逼近等深刻结果。  相似文献   
40.
For a simple multivariate regression model, nonparametric estimation of the (vector of) intercept following a preliminary test on the regression vector is considered. Along with the asymptotic distribution of these estimators, their asymptotic bias and dispersion matrices are studied and allied efficiency results are presented.  相似文献   
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