误差的均方

The second chapter mainly compares the superiority between ridge estimate and James-Stein estimate under the generalized mean squared errors criterion, and gives a improvement method about ridge estimate under growth curve model, and gives a comparison with ridge estimate.

论文第二章，在广义均方误差准则下比较了James -Stein估计和岭估计的优良性，又提出了生长曲线模型中参数岭估计的一种改进方法，并将提出的新估计与已有的岭估计作了比较。

There exist many literatures concerning the research that the biased estimators with certain restricted conditions outperform the least squares estimator under the criterion of the mean-square error.

2在均方误差准则下，满足一定约束条件的有偏估计优于最小二乘估计的研究相当多，在Pitman准则下的类似研究存在比较大的困难。

From the analysis,we can relate the convergence and the mean square error in terms of the slope and the clipping level of the nonlinear function.

根据该分析，可以将NRLS的收敛和均方误差表示为非线性函数的斜率和限幅水平的函数。

Computer simulations show that the scheme proposed increases the transmission efficiency, and at the same time, can obtain lower error bit rate and mean square error of channel estimation than conventional OFDM systems with relative low complexity.

仿真实验表明，该策略可提高传输效率、增强系统的抗噪性能、获得比传统OFDM系统更低的信道估计均方误差和误码率，且具有较低的计算复杂度。

A new compression algorithm of historical data is presented from the mean square error of view in this paper and compared with the well-known swinging door algorithm developed by OSI Software Inc.

文章基于均方误差的设计思想，提出了一种新的历史数据压缩算法、给出其详细步骤，并和OSI软件公司开发的旋转门算法进行比较。

Based on the analysis of the Doppler effect of the mobile channel, the performance of two MIMO-OFDM systems (STTC-OFDM and SFBC-OFDM) in the fast-moving environment is studied. Then, the algorithm for channel estimation based on the training sequence is extended into the fast-moving environment by introducing the space-frequency coding, the method of the equal-interval pectinate pilot-inserting, and the complete Maximum-Likelihood space-frequency decoding.

针对快速移动环境中存在的多普勒效应，研究了两种多输入多输出正交频分复用系统在快衰落信道中的误码性能，采用空频编码梳状等间隔导频插入方式，以及完全最大似然空频分组码解码算法，使用导频与接收信号进行信道参数估计，将一般多输入多输出正交频分复用系统中的基于训练序列的最小均方误差信道估计算法推广到了快衰落信道环境中。

Considering the fat-tail phenomenon that may exist in practical data, we have also studied the PTLE for the multi-t distribution model based on the three large sample tests above. Performances of the estimators according to the quadratic bias and mean square error are similarly compared in detail.

考虑到实际数据可能存在的厚尾情况，本文研究了文献中讨论颇多的多元t分布模型的基于大样本检验的等式约束预检验Liu估计，并同样在平方偏差和均方误差两个准则下对其优良性进行了详细比较。

We give the approximation formulas of the variance of the sample ratio estimator for a population mean and its asymptotically non-biased estimator in multi-stage sampling.

讨论多阶段抽样比率估计及其样本量选择的问题，给出了比率估计抽样均方误差的近似公式及其渐近无偏估计的公式。

The superiority of a class of linear estimator with respect to generalized least square(GLS estimator of regression coefficients was studied in terms of the mean square error matrix(MSEM criterion, and the lower bound and super bound of three relative efficiencies were obtained respectively.

在均方误差矩阵准则下研究了回归系数的一类线性估计相对于广义最小二乘估计的优良性问题，并讨论了三种不同相对效率的上、下界。

The objective function of the optimization problem consists of both the performance metrics of the image fusion, such as the root mean square error, and those of individual filters.

该优化问题的目标函数包括了图像融合的性能指标，如最小均方误差以及一些与传统滤波器相关的性能指标，包括阻带和通带能量。

According to the clear water experiment, aeration performance of the new equipment is good with high total oxygen transfer coefficient and oxygen utilization ratio.

曝气设备的动力效率在叶轮转速为120rpm～150rpm时取得最大值，此时氧利用率和充氧能力也具有较高值。

The environmental stability of that world - including its crushing pressures and icy darkness - means that some of its most famous inhabitants have survived for eons as evolutionary throwbacks, their bodies undergoing little change.

稳定的海底环境─包括能把人压扁的压力和冰冷的黑暗─意谓海底某些最知名的栖居生物已以演化返祖的样态活了万世，形体几无变化。