explain why When the alternative hypothesis states that the

explain why When the alternative hypothesis states that the difference between two groups can only be in one direction, we call this a:

One-tailed test

Bi-directional test

Two-tailed test

Non-parametric test

Solution

One-tailed test, as it given the diffrencce go in one direction either it can be increment or decrement. It defined to be U1>U2 or U1<U2