发布日期 ： 2021-01-28 01:22:39 UTC
分类 ： Probability
Suppose the two populations X and Y are independent of each other and obey the normal distribution. The mean and variance of X areμ<sub>1</sub>,σ<sub>1</sub><sup>2</sup>, The mean and variance of Y areμ<sub>2</sub>,σ<sub>2</sub><sup>2</sup>, that is X~N(μ<sub>1</sub>,σ<sub>1</sub><sup>2</sup>), Y~N(μ<sub>2</sub>,σ<sub>2</sub><sup>2</sup>),This page is atσ<sub>1</sub><sup>2</sup>,σ<sub>2</sub><sup>2</sup> for known cases mean difference μ<sub>1</sub>-μ<sub>2</sub>as hypothetical test，the statistics are
<img align="middle" alt="" src="http://drr.ikcest.org/static/upload/da/dad25624-e971-11e9-bab5-00163e0618d6_m.jpg" style="width: 150px; " >，among them, n<sub>1</sub>,n<sub>2</sub> are two overall sample sizes. <br >