====== 点二列相关 Point Biserial Correlation ======
**点二列相关的适用情况**Application of point biserial correlation：\\
  - 一列为正态等距变量
One column is a normal equidistant variable\\
  - 另一列为二分命名变量
The other column is a dichotomous named variable\\
  - 常用于试卷的信度分析
Often used in reliability analysis of test papers\\

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**点二列相关的公式**Formulas for point biserial correlation：\\
{{ ::点二列相关系数公式.png?200 |}}

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**r<sub>pb</sub>与t的关系**r<sub>pb</sub> versus t：\\
{{ ::rpq与t之间关系.png?300 |}}\\
其中n<sub>1</sub>、n<sub>2</sub>分别为两点变量的样本分布。\\
Where n<sub>1</sub>,n<sub>2</sub> are the sample distributions of the two point variables respectively.