For a study using a t test for independent means, the approximate number of participants needed for 80% power for an estimated small effect size and using a one-tailed test is:
A)50
B)64
C)310
D)393

Question

Quizplus · Accepted Answer

For a small effect size, a larger sample size is needed to achieve 80% power. Typically, around 310 participants are required for a one-tailed test with a small effect size.

For a Study Using a T Test for Independent Means