Assuming the same sample size is used, how does changing the significance level from 0.2 to 0.05 affect the power of a test?
A)The power decreases.
B)The power increases.
C)The power does not change.
D)The power does change, but it might either decrease or increase.
E)It is not possible to predict whether the power will increase, decrease, or remain the unchanged.

Question

Assuming the same sample size is used, how does changing the significance level from 0.2 to 0.05 affect the power of a test? ​
A)The power decreases.
B)The power increases.
C)The power does not change.
D)The power does change, but it might either decrease or increase.
E)It is not possible to predict whether the power will increase, decrease, or remain the unchanged.

Quizplus · Accepted Answer

Lowering the significance level from 0.2 to 0.05 reduces the probability of making a Type I error (rejecting a true null hypothesis). However, this also makes the test more conservative, requiring stronger evidence to reject the null hypothesis, which can lead to a higher probability of a Type II error (failing to reject a false null hypothesis), thereby decreasing the power of the test.

Assuming the Same Sample Size Is Used, How Does Changing