Question

What happens to the rejection region as the level of significance decreases?

(a) Rejection region becomes smaller
(b) Rejection region becomes larger
(c) Rejection region remains the same
(d) Rejection region disappears entirely

Answer 1

The rejection region becomes smaller as the level of significance decreases.

Step-by-step explanation:

The correct answer is (a) Rejection region becomes smaller.

The rejection region is the set of values in the sample space for which the null hypothesis is rejected. The level of significance, often denoted by alpha (α), determines the boundary of the rejection region. As the level of significance decreases, the rejection region becomes smaller. This means that the null hypothesis is less likely to be rejected.

For example, if the level of significance is 0.05, then the rejection region corresponds to the 5% of the sample space that leads to rejecting the null hypothesis. If the level of significance is decreased to 0.01, then the rejection region becomes smaller and corresponds to only 1% of the sample space.