Which of the following would increase the power of a test?
I.Increase the sample size
II.Decrease the significance level
III.Increase alpha
A)I only
B)II only
C)III only
D)I and II
E)I and III

Question

Quizplus · Accepted Answer

Increasing the sample size (I) makes it easier to detect a true effect if one exists, thus increasing the power of a test. Increasing alpha (III) also increases the power because it raises the probability of rejecting the null hypothesis when it is false, albeit at the cost of increasing the Type I error rate. Decreasing the significance level (II) would actually decrease the power of a test, as it makes the criteria for rejecting the null hypothesis more stringent.

Which of the Following Would Increase the Power of a Test