方差,variance
1)variance[英]['ve?ri?ns][美]['v?r??ns]方差
1.Improving methods to calculate estimator minimum variance of the finite population mean;总体均值估计量最小方差的改进
2.Image compression based on the criterion of variance and energy;基于能量和方差标准的图像压缩方法
3.A real time fault diagnosis system based on variance of power spectrum at characteristic frequency;基于特征频率功率谱方差的故障实时检测
英文短句/例句

1.unbias(s)ed variance无偏方差, 均方差
2.variance-covariance propagation law方差-协方差传播律
3.nonscalar variance-covariance matrix非纯量方差-协方差矩阵
4.The square of the standard deviation.方差标准偏差数的平方
5.sample variance-covariance matrix样本方差-协方差矩阵
6.variance components method方差分析法 方差分析法
7.Variance Component Esti mation with Gross Errors or Systematic Errors含有粗差或系统误差的方差分量估计
8.Comparative Research on Analysis of Covariance for Difference Value and Analysis of Covariance;“差值的方差分析”与协方差分析的比较研究
9.Interval Estimation of Mean Square Error for Linerar Statistic Model;统计模型中误差方差的均方误差的区间估计
10.The positive square root of the variance is called the standard deviation.方差的正的平方根叫做标准差。
11.A GENERALIZED VARIANCE-RATIO TEST FOR A HETEROSKEDASTIC REGRESSION;异方差回归中的广义方差比检验(英文)
12.Discussions on prospected error of observation s systematic error and comprehensive error;关于观测值系统误差与综合误差的方差的探讨
13.The Comparison of the Risk Measuring Methods Based on the Semi-Variance and Variance基于方差与半方差的风险刻画方法比较
14.Empirical Likelihood Ratio Confidence Regions for the Differences of Two Populations Variance两总体方差差异的经验似然置信区间
15.covariance for simple random sampling简单随机抽样协方差
16.alternate test for variance heterogeneity非齐性方差的替换检验
17.Uniformly minimum variance unbiased estimate方差一致最小无偏估计
18.ANLAB colour-difference equationANLAB色差方程
相关短句/例句

deviation[英][,di:vi'e??n][美]['div?'e??n]方差
1.After several discrete wavelet transforms, another expression of the deviation of white noise on every scale is given by us.推导出了经过多次离散小波变换后,白噪声在不同尺度上方差的另外一种表达式,应用到小波域硬阈值滤波中,通过数字仿真发现,二进小波的计算量较大,滤波效果较好,离散小波的计算量较小,滤波效果稍差,并对原因进行了说明。
2.The author thinks that sampling methods should be chosen according to the characteristics of cases studies and phasing of deducing should be replaced by direct stratificated to optimize the calculation of deviation which can make case deducing studies scientific and more practicable.本文针对现行限额以下贸易业抽样调查方案在实施过程中反映出来的问题 ,提出了融复合分层和顺序抽选阶段于一体的架构及灵活地选用不同的抽样方法 ,改分阶段推断为直接分层推断 ,优化抽样方差计算等设想 ,目的在于使调查方案更科学、更具有可操作性。
3)square deviation方差
1.The mean value and square deviation of residence time measured at different outlet with different stirring speeds and flow rates were calculated and analyzed by L_9(3~3) orthogonal experiments.用NaCl溶液做示踪剂测定该管式反应器内的停留时间分布(RTD)曲线,并计算了平均停留时间和方差
2.Taking the minimum square deviation of the irrigation rate and successive images over the whole irrigation duration as objective function, this model considers 4 kinds of possible adjustment approaches and the corresponding adjustment rules in the actual applications.该模型以保证灌水率方差在总灌水延续时间内最小和图像连续为目标函数 ,考虑了实际中 4种可能的调整途径及相应的调整规则。
4)Variances[英]['v??ri?ns][美]['v?r??ns]方差
1.Estimations of the means and variances from normal populations under simultaneous semi-order restrictions;半序约束下正态均值和方差的估计
2.And also,we obtained the statistical properties of the expected values and variances of implied standard deviations,while changing the powers or striking prices.并改变期权中幂的值或执行价格的值,得到隐含标准差的期望和方差等统计特征。
3.Different from the usual way of obtaining the network parameters via iterative training,a kind of centers,variances and weights direct determination method is revisited based on matrix pseudo-inverse and/or inverse in this paper.区别于反复迭代训练而得到网络参数的惯常做法,重新探讨一种基于矩阵伪逆或逆的中心、方差及权值可直接确定的方法。
5)standard deviation方差
1.Data expectation,standard deviation,the space between the especially apices,the distance of especially poles and the width of the half especially poles of section data define as factor of this method.利用地球物理异常显示参数表示剖面数据,以剖面数学期望、方差、特征峰间距、特征峰半极值为信息参数,对放射性测量剖面进行模糊聚类分析。
2.In order to assess the veracity of scheduled loss ratio,the standard deviation between scheduled loss ratio and practical com-pleting value was utilized to express the precision.以线损理论计算为基础,并充分考虑站用电、低压配网损耗、管理线损,给出了计划线损率的计算公式,并提出利用计划线损率与实际完成线损率之间的最小方差来衡量其科学性。
6)error variance误差方差
1.Admissible nonhomogeneous quadratic form estimate of error variance in linear models;线性模型中误差方差的非齐次二次型可容许估计
2.An interval estimator of error variance in nonparametric regression model;回归误差方差的区间估计
3.Let σ_n be the bootsrapping estimator of σ~2 that is error variance in the linear model.设(?)~2为线性模型中误差方差σ~2的Bootstrap量,讨论了误差方差的Bootstrap估计量分布的逼近速度,这个结果类似关于u统计量的有关结论。
延伸阅读

方差方差variance表示随机变量与它的数学期望间偏离程度的量。是随机变量的基本数字特征之一。其算术平方根称为标准差。一个随机变量的方差越小,表明这个随机变量与它的数学期望越接近,否则,随机变量的取值则较离散。例如某校有两个班级,一个班的考生,考试成绩50分、60分和70分的各10人;而另一个班考生的成绩20分、60分和100分的各10人,这两个班的平均分数都是60分,但并不能说这两个班的学生学习成绩是相同的,因为它们的离散程度不同,第一个班的方差为1/3×(50-60)2+1/3×(60-60)2+1/3×(70-60)2=66.67,而第二个班的方差为1/3×(20-60)2+1/3×(60-60)2+1/3×(100-60)2=1066.67,它远远大于66.67,即说明第二个班的学生学习程度相差比较悬殊,而第一个班的学习程度比较平均。