意思是：相关系数；
句子实例：
A correlation coefficient in which one variable is many-valued and the other is dichotomous.
一个多值变数和一个双值变数的相关系数。
The approximation of the distribution is justified by looking at two correlation coefficients.
通过计算两类相关系数，证明了该近似分布函数的合理性。
