You plan to conduct a study where your nondirectional hypothesis will be assessed with a t test for independent means at the .05 significance level.If you are predicting a large effect size,how many participants would you need in total (assuming equal Ns per group)to obtain 80% power?
A)20
B)26
C)40
D)52

Question

Quizplus · Accepted Answer

To calculate the sample size needed under these conditions, we can use a power analysis. Assuming a large effect size, an alpha level of .05, and 80% power, we can input these values into a power analysis calculator. With these inputs, we find that we would need a total sample size of 52 participants, with 26 participants in each group. Therefore, the best choice is D.

You Plan to Conduct a Study Where Your Nondirectional Hypothesis