Using a one-tailed test allows us to increase statistical power over a two-tailed test because it:
A) divides the alpha into two tails but only focuses on one of those tails.
B) divides the alpha into two tails, which reduces the size of each.
C) puts the entire alpha into one tail, increasing the chances of rejecting the null hypothesis.
D) puts the entire alpha into one tail, decreasing the chances of rejecting the null hypothesis.

Question

Quizplus · Accepted Answer

Using a one-tailed test puts the entire alpha into one tail, which increases the chances of rejecting the null hypothesis. This is because we are only focused on one direction of the distribution (either above or below a certain value) and not considering the possibility of extreme values in the opposite direction. By not dividing the alpha into two tails, we have more power to detect an effect in our specified direction.

Using a One-Tailed Test Allows Us to Increase Statistical Power