查询词典 estimator

Second,a new estimator called generalized rootpower estimator of regression coefficients in growth curve model is obtained.For the newestimator,its superiority over the LS estimator and the root power estimator,and its admissibilityare proved.Two methods,two kinds of arithmetic of choosing the generalized root powerparameters are introduced.A demonstrative practical example is provided.

对增长曲线模型中的回归系数矩阵提出了一种新的估计——广义根方估计，并证明了通过广义根方偏参数的适当选取可使得该估计在均方误差和均方误差矩阵的意义下优于已有的最小二乘估计估计和根方估计；及证明了广义根方估计是可容许估计；还给出了选取广义根方偏参数的两种方法、算法和应用实例。

In the end, we can see the performance of MMSE estimator is the best, and the performance of LS estimator is the worst, while for the complexity of the three channel estimator methods, the condition is reverse comparing with the condition of the performance.

最后我们可以看出MMSE估计的性能要远好于LS估计，但其复杂度较高，SVD估计的性能及运算复杂度皆介于前两者之间。

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。

There are two findings summarized from previous studies:(1) the least squares estimator is a common choice of researchers, but under an unequal probability design, the estimator is biased,(2) the probability weighted estimator is consistent but may have a large variance.

过去的研究发现：(1)在不等机率抽样时，一般常用的最小平方法所得到的回归参数估计式并非不偏估计式；(2)机率加权最小平方法可以改善不偏性，然却增加估计的变异程度。

SNR maximum likelihood estimator based on data directed decision was evaluated first, and was concluded as a biased estimator. An unbiased estimator can be acquired through high order moments of received data.

摘要通过对基于判决反馈的信噪比最大似然估计推导过程的分析，得出：判决反馈最大似然估计得到的估计值是有偏估计；利用基带数据的高阶矩特性，可以获得渐近无偏估计。

Combining NA samples the EB estimation with convergence rates is also obtained; Thirdly, for one-parameter exponential distribution family, we give the parameters' EB estimator that is admissible and asymptotically optimal with convergence rates. Finally, Bayesian and hierarchical Bayesian approaches are applied to analyze the reliability performances for series system with cold standby units and the numerical simulation results show that multiple Bayes estimator is superior to Bayes estimator.

其次，针对一类双边截断分布族，在非对称linex损失下构造了经验Bayes决策函数，建立了它的收敛速度，给出了渐近最优的证明；并结合NA样本研究了参数的经验Bayes估计及其收敛速度；接着给出了指数族参数的经验Bayes估计，证明了它是渐近最优的，也是可容许的，同时也获得了该EB估计的收敛速度；最后，运用Bayes与多层Bayes方法研究了具有冷贮备部件串联系统的可靠性指标的估计，并给出了数值模拟结果，结果表明多层Bayes估计优于Bayes估计。

The main results are as follows:We review the existing Monte Carlo control variates estimators of the price of Asian options and propose a new one. According to pratical needs, we define efficiency as the inverse of the product of the variance of an estimator and its computational time and make it a standard for comparisons to draw the following conclusions: Firstly, the more control variates correlate with arithmetic average Asian options, the larger is the efficiency of an estimator with these control variates, but among which the geometric average option plays the most important role; Secondly, an estimator with more control variates is better than one with less ones only when the time to maturity is long and the volatility is high.

在综合已有研究工作的基础上，本论文的主要创新成果如下：（1）我们回顾了已有的亚洲期权价格的蒙特卡罗控制变量估计，并提出了一个新的控制变量估计，且从客观实际出发，将估计值的方差和计算时间的乘积的倒数定义为效率并以它为标准比较各估计，得到以下结论：与算术平均亚洲期权相关程度越大的控制变量构成的估计的效率越大，而其中起主要作用的控制变量为几何平均亚洲期权的价格；只有在到期时间较长且标的资产的波动率较大时，元素多的多元控制变量估计比元素少的效率大。

OD estimation was divided into fixed steps, with every step containing a bi-level programming. The upper-level problem was a generalized least squares estimator, while the lower level problem was a stochastic user equilibrium model. Namely, based on generalized least squares estimator and stochastic user equilibrium, a new estimator of the OD matrix was proposed by target matrix and traffic counts updating.

将OD估计分为固定的步数，每一步都是一个双层规划，上层为广义最小二乘估计，下层为随机用户均衡分配模型，即以广义最小二乘估计和随机用户均衡分配模型为基础，通过更新估计模型中目标矩阵和实测路段上的流量来估计OD矩阵。

Also in the paper,we get the point estimator of unknown parameters by using the maximum likelihood estimator method and simulated moment estimator method based on the censored sample.

给出了其寿命分布函数步进形式，在截尾样本场合利用极大似然估计方法和拟矩估计方法求出了未知参数的点估计，最后利用计算机模拟考察了说明本文方法的可行性。

With regard to the estimation of the variance components, many statisticians proposed a number of approaches, such as the Analysis of Variance Estimator, Maximum Likelihood Estimator, Restricted MLE, and the Minimum Norm Quadratic Unbiased Estimator, etc.

关于方差分量的估计统计学家们提出了许多方法，如方差分析估计，极大似然估计，限制极大似然估计，最小范数二次无偏估计等。

Putt your way through 36 fun-filled holes of minigolf on 3D designed courses with elevated greens, bunkers, bridges and water hazards, among other crazy obstacles.

您的推杆方式，通过36个有趣的填孔迷你的三维设计的课程，以提升绿党，掩体，桥梁和水的危害，除其他疯狂的障碍。

Some participles can be used either as attributes or as predicatives.

有些分词既可当定语用，也可当表语用。