In a study with a non-directional hypothesis…
A) There is a single rejection region with an area that corresponds to the alpha level.
B) There is a single rejection region with an area that corresponds to the p-value.
C) There are two rejection regions that have the same area that adds up to the alpha level.
D) There are two rejection regions that have the same area that adds up to the p-value.

Question

Quizplus · Accepted Answer

In a non-directional hypothesis, we are testing for any significant difference, regardless of the direction. This means that we need to consider the possibility of the difference being in either direction. Therefore, we need two rejection regions, one for each tail of the distribution. Each of these rejection regions should have half of the alpha level, so that when added together, they equal the full alpha level. For example, if our alpha level is 0.05, each rejection region would have an area of 0.025, and so the total alpha level would be 0.05.

In a Study with a Non-Directional Hypothesis…