Under which of these circumstances can a one-tailed test of significance be used?
A) whenever the alpha level exceeds 0.10
B) whenever the researcher feels like it
C) whenever the researcher can predict a direction for the difference
D) whenever the null hypothesis is thought to be true

Question

Quizplus · Accepted Answer

A one-tailed test is appropriate when the researcher has a specific hypothesis about the direction of the effect or difference they are testing.

Under Which of These Circumstances Can a One-Tailed Test of Significance