查询词典 estimators

Describes general methods of point and interval parameter estimation and the small and large sample properties of estimators: method of moments, maximum likelihood, unbiased estimation, Rao-Blackwell and Lehmann-Scheffe theorems, information inequality, asymptotic relative efficiency of estimators.

点估计和区间估计的一般方法，估计量的小样本和大样本性质：矩法，极大似然估计，无偏估计，Rao-Blackwell 和 Lehmann-Scheffe 理论，信息不等式，渐进相对有效估计量。

In this paper, three robust estimators: robust best invariant quadratic unbiased estimator, robust minimum norm quadratic unbiased estimator and robust Helmert estimator have been designed. Finally, this paper states that these three classical estimators are particular cases of the RBIQUE.

导出了稳健最优不变二次无偏估计、稳健最小范数二次无偏估计、稳健Helmert估计，并说明了最优不变二次无偏估计、最小范数二次无偏估计以及Helmert估计等均是稳健最优不变二次无偏估计的特例。

To overcome this problem, many authors proposed some biased estimators to alternate the least squared estimator. In some sense, these estimators improved the least squared estimator.However, the biased estimator was apart from the true value of parameter, so some statisticians proposed the notation of the almost unbiased estimator.

人们发现设计阵的"病态"是导致Stein现象的根源，为了克服共线性性，人们在文献中相继提出了许多有偏估计来替代最小二乘估计，这些估计从某种意义上讲，都改进了最小二乘估计。

And then some ellipses that AUGR estimator is better than the OLS estimator and AUGL estimator is better than the OLS estimator are given, respectively.Second, the definition of the almost unbiased unified biased estimator is proposed. This definition includes the familiar almost unbiased estimators in literatures, and it is the unified expression of the familiar almost unbiased estimators. Followed the biased and variance are compared of AUUB estimator and the unified biased estimator, respectively. AUUB estimator has smaller bias than UB estimator and the variance of AUUB estimator is between the variance of UB estimator and 4 times of the variance of UB estimator. Finally the properties of AUUB estimator are discussed. The conclusion is gained that there are parameters made AUUB estimator is better than OLS estimator in terms of their mean square error. The sufficient and necessary condition that AUUB estimator is admissible is given. The ellipse is given that AUUB estimator is

然后给出了几乎无偏统一有偏估计的定义，该定义包括了文献中常见的几乎无偏估计，实现了常见几乎无偏估计的统一表达式；接下来我们比较了几乎无偏统一有偏估计与统一有偏估计的偏度与方差，得出了几乎无偏统一有偏估计比统一有偏估计有较小的偏度，几乎无偏统一有偏估计的方差介于统一有偏估计的方差与统一有偏估计的方差的四倍之间的结论；最后我们对统一有偏估计的主要性质作了讨论，证明了存在参数K，S使得几乎无偏统一有偏估计在均方误差意义下优于最小二乘估计的结论，给出了几乎无偏统一有偏估计为可容许估计的充要条件，还给出了在均方误差阵意义下几乎无偏统一有偏估计优于最小二乘估计的椭球。

The thesis analyzes the methods for parameter estimation of distributed sources in detail, and low complexity estimators, comes up with RELAX in parameter estimation and robust method of high resolution parameter estimators for distributed sources, and gives theory analysis and simulation results. The main work is:1 This text gives a study of the signal models of two kinds of distributed sources: coherent distributed sources and incoherent distributed sources, analyzes eigenvalue distribution of correlation matrix.2 Systematically introduced parameter estimation of distributed sources on the base of models, including the maximum likelihood estimate, least squares estimator, DSPE, DISPARE, etc.

论文详细分析了已有分布式目标参数估计方法及低复杂度的参数估计方法，提出了分布式目标参数估计的RELAX算法和具有稳健性的分布式目标高分辨估计方法，并给出了相应的理论分析和仿真实验结果。

Using the result for non-restricted model, we transform the restricted model to common model, and multi collectivity model to single collectivity model, thus, the necessary and sufficient conditions that nonhomogeneous linear estimators for Sβ are admissible in the class of nonhomogeneous linear estimators are obtained which filled the blank for admissibility for restricted linear model.

对线性等式约束的共同均值线性模型，利用无约束单总体模型的现有结果，通过适当变换，把等式约束模型向无约束转换，并把多总体转换为单总体，在矩阵损失下找到了均值参数β的条件可估函数Sβ的线性估计∑mAiyi+a在非齐次线性估计类中可容许的充要条件，填补了等式约束的共同均值线性模型可容许性方i=1面的空白。

First, this paper gives an introduction of some methods of unequal probability sampling, their estimators and variance estimators, including sampling with pps with replacement, methods of sampling without replacement suggested by Brewer, Durbin, Sampford , Des Raj , Murthy , Rao-Hartley-Cochran. Then, at the basis of Rao and Bayless's study , we consider that population can be splited two random subpopulations, which are respectively drawn from different infinite super-populations, and compare the stabilities of estimators of the methods that given above.

本文首先从理论上介绍了若干种不等概率抽样方法，它们的估计量、估计量的方差及其估计，其中包括有放回PPZ及PPS抽样，不放回不等概率抽样中的Brewer、Durbin、Sampford、Des Raj，Murthy、Rao-Hartley-Cochran等人的方法；其次，在Rao和Bayless两人就样本单元数n=2的情形对上述抽样方法进行比较的基础上，将总体随机地分成两个子总体，视每个子总体取自不同的线性超总体，在文中，我们利用计算机实现随机分组，并通过画图比较各方法估计量的稳定性，结果表明，对变异系数C.V。

First, this paper gives an introduction of some methods of unequal probability sampling, their estimators and variance estimators, including sampling with pps with replacement, methods of sampling without replacement suggested by Brewer, Durbin, Sampford , Des Raj , Murthy , Rao-Hartley-Cochran.Then, at the basis of Rao and Baylesss study , we consider that population can be splited two random subpopulations, which are respectively drawn from different infinite super-populations, and compare the stabilities of estimators of the methods that given above.

本文首先从理论上介绍了若干种不等概率抽样方法，它们的估计量、估计量的方差及其估计，其中包括有放回PPZ及PPS抽样，不放回不等概率抽样中的Brewer、Durbin、Sampford、Des Raj，Murthy、Rao-Hartley-Cochran等人的方法；其次，在Rao和Bayless两人就样本单元数n=2的情形对上述抽样方法进行比较的基础上，将总体随机地分成两个子总体，视每个子总体取自不同的线性超总体，在文中，我们利用计算机实现随机分组，并通过画图比较各方法估计量的稳定性，结果表明，对变异系数C.V。

For the multisensor linear discrete time-varying stochastic control systems with the different local dynamic models, using the Kalman filtering method, under the optimal fusion criterion weighted by scalars, the unified and universal optimal information fusion white noise deconvolution estimators are presenced, and for the corresponding time-invariant systems, the steady-state optimal information fusion white noise deconvolution estimators are also presented.

对于带不同局部动态模型的多传感器线性离散时变随机控制系统，应用Kalman滤波方法，在按标量加权最优融合准则下，提出了统一和通用的最优信息融合白噪声反卷积估值器，并对定常系统提出了稳态最优信息融合白噪声反卷积估值器。

For the multisensor linear discrete time-varying stochastic control systems with the different local dynamic models, using the Kalman filtering method, under the optimal fusion criterion weighted by scalars, the unified and universal optimal information fusion white noise deconvolution estimators are presenced, and for the corresponding time-invariant systems, the steady-state optimal information fusion white noise deconvolution estimators are also presented.

黑龙江大学自动化系，哈尔滨150080中文摘要：对于带不同局部动态模型的多传感器线性离散时变随机控制系统，应用Kalman滤波方法，在按标量加权最优融合准则下，提出了统一和通用的最优信息融合白噪声反卷积估值器，并对定常系统提出了稳态最优信息融合白噪声反卷积估值器。

This is not an ordinary box, which is used as a background picture of the dialog box, very pretty.

详细说明：这可不是一个一般的对话框，它是用图片作为背景的对话框，非常好看。

Conceal me what I am,and be my aid for such disguise as haply shall become the form of my intent.

遮掩我的身份，帮助我，我的面具将成为我的目的。