This tool is used to test the null hypothesis that there is no difference between two population means against either one-sided or two-sided alternative hypotheses.

此工具用于检验两个总体平均值之间不存在差异的空值假设，而不是单方或双方的其他假设。

youdao

The second one is two-sided hypothesis test problem.

第二个是双边假设检验问题。

youdao

They are a spirited one-day and Twenty20 side, but three Test match victories in 10 years is not good enough - and Test cricket simply cannot afford to produce one-sided contests with Twenty20 cricket around.

BBC: Jonathan Agnew column

It is a view that would find plenty of backing among those who feel a Test match between Australia and Bangladesh is simply too one-sided to benefit anyone.

BBC: Champion for the underdog