non-parametric confidence interval

例句：

1. 1. The non-parametric test is used to compare the means of two independent samples without assuming that the distributions are normal.
   非参数测试用于比较两个独立样本的均值，而无需假设分布是正态的。
2. 2. In this study, we used a non-parametric method to estimate the population mean.
   在本研究中，我们使用了非参数方法来估计总体均值。
3. 3. The non-parametric approach has been shown to be more robust than parametric methods in certain situations.
   在某些情况下，非参数方法比参数方法更稳健。