When the sample size is great, QIF approach shows that the selection of working correlation is same to the selection of unbiased estimating equation.
当样本量较大时，QIF方法表明工作相关阵的选择等价于无偏估计方程的选择。
2
According to the special structure of unitary code, it is very simple to analyze the effect of fading correlation from the equationof PWEP.
鉴于酉空时码的独特结构，在差错概率公式中可以很容易地分析衰落相关系数矩阵带来的影响。
3
Moreover, the fitting degree of curvilinear regression equation is tested by correlation index, in stead of correlation coefficient which has been unsuitably used for testing in similar works.