Whenever the alternative hypothesis is written as "mean 1 is greater than mean 2", then
A) a one-tail t test is allowed
B) only a two-tail t test is allowed
C) an independent t test is not allowed
D) sample sizes must be greater than 30

Question

Quizplus · Accepted Answer

When the alternative hypothesis specifies a direction ("mean 1 is greater than mean 2"), a one-tail t-test is allowed. The directionality allows for a more specific test of the hypothesis, rather than just looking for a difference between the means. The other answer choices are not necessarily true or relevant for this scenario.

Whenever the Alternative Hypothesis Is Written as "Mean 1 Is