区间估计

求谁	$\sigma是否已知$	置信区间	置信区间
求$\mu$	$\sigma未知$	$1-\alpha$	$(\overline X- \frac{\sigma}{\sqrt(n)}Z_{\frac{\alpha}{2}},\overline X+\frac{\sigma}{\sqrt(n)}Z_{\frac{\alpha}{2}})$
求$\mu$	$\sigma已知$	$1-\alpha$	$(\overline X- \frac{\sigma}{\sqrt(n)}t_{\frac{\alpha}{2}}(n-1),\overline X+\frac{\sigma}{\sqrt(n)}t_{\frac{\alpha}{2}}(n-1))$
$求\sigma$	$\sigma未知$	$1-\alpha$	$(\overline X - \frac{\sqrt{n-1}S}{\sqrt{\chi^2_{\frac{\alpha}{2}}(n-1)}},\overline X + \frac{\sqrt{n-1}S}{\sqrt{\chi^2_{1-\frac{\alpha}{2}}(n-1)}})$

来源：CSDN

作者：Philtell

链接：https://blog.csdn.net/CCCrunner/article/details/103810034