查询词典 unbiased

At the same time, we prove that the best linear unbiased prediction of a linear predictable variable Qy and the best linear unbiased prediction βn=(X"sV-1Xs)-1 X"sVs-1ys of regression coefficients of the finite populations βn=(X"V-1X)-1X"V-1y are admissible under matrix loss function and in the class of the linear predictions and the class that contains all predictions, and under quadratic loss function in the class of the linear predictions.

在线性预测类和一切预测类中是可容许预测，而在二次损失函数下其在线性预测类中是可容许预测。

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。

Secondly, in this study, China's staple food demand is offered to have both long-term and short-term stability, and it fits the "best linear unbiased estimator", goodness of fit , hence it is predictable and has long-term developing co-relation--the rise of food consumption causes the rise of food price and the increase of food consumption stimulate the increase of income.

实证结果发现：中国粮食长、短期发展具稳定性、最小变异线性不偏估计式(best linear unbiased estimator，BLUE)、有配适性且残差变异数齐一，亦无自我相关性、故具可预测性与长远发展关系，乃粮食消费增加，刺激粮食售价的攀升；粮食消费量增加，刺激所得增加。

Though the almost unbiased estimator was still a biased estimator, it has smaller bias than corresponding biased estimator.In this paper, we first study the properties of the almost unbiased generalized ridge estimator and the almost unbiased generalized Liu estimator.

但有偏估计毕竟偏离参数的真值，因此学者们又提出了几乎无偏估计的概念，虽然几乎无偏估计仍然是有偏估计，但是它比相应的有偏估计有更小的偏度。

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。

When the estimator is unbiased, the numerical estimate is frequently also called unbiased.

当估计量无偏时，数字估计值也常叫做无偏的。

The adjusted R-square is still not an unbiased estimator of the population R-squared, because the ratio of two unbiased estimators is not an unbiased estimator.

调整过的R2仍不是总体R2的一个无偏估计量，因为两个无偏估计量的比例不是一个无偏估计量。

By means of combinatin of unscented transformation and best linear unbiased filter, a new filter named unscented transformation-best linear unbiased estimator filter was proposed to solve the above nonlinear tracking problem.

通过将无迹变换与最优线性无偏滤波器有机结合，提出一种新的BLUE滤波算法，以便解决上述非线性跟踪问题。

The competing ostariophysan topologies were tested by using the approximately unbiased test, the Kishino-Hasegawa test, and the Shimodaira-Hasegawa test.

采用approximately unbiased test、Kishino-Hasegawa test和Shimodaira-Hasegawa test检验相互竞争的拓扑树或系统育假设。

A software for QTL mapping—QTLMapper 2. 0 written by C/C++ language was developed. The sotftware could analyze populations of DH, RIL, F〓 and permanent F〓, and could provide unbiased estimation for all genetic main effects and/or unbiased prediction for all QE interaction effects. The software could also predict heteroses of single-cross offspring based on QTL genetic main effects and/or QE interaction effects obtained in QTL analysis of F〓 or permanent F〓 population.

用C／C++语言编写了适于分析DH群体、RIL群体、F〓群体和永久F〓群体的QTL作图软件QTLMapper 2.0，能够提供对各项遗传主效应的无偏估计和／或对QE互作效应的无偏预测，还能基于F〓群体或永久F〓群体估计的QTL遗传主效应和／或QE互作效应预测单交后代杂种优势。

The absorption and distribution of chromium were studied in ryeusing nutrient culture technique and pot experiment.

采用不同浓度K2CrO4(0，0.4，0.8和1.2 mmol/L)的Hoagland营养液处理黑麦幼苗，测定铬在黑麦体内的亚细胞分布、铬化学形态及不同部位的积累。

By analyzing theory foundation of mathematical morphology in the digital image processing, researching morphology arithmetic of the binary Image, discussing two basic forms for the least structure element: dilation and erosion.

通过分析数学形态学在图像中的理论基础，研究二值图像的形态分析算法，探讨最小结构元素的两种基本形态：膨胀和腐蚀；分析了数学形态学复杂算法的基本原理，把数学形态学的部分并行处理理念引入到家实际应用中。