0 votes
in Use of WebPower by PL (150 points)

I am calculating the needed sample size for a new experiment using wp.rmanova function. The experiment is a fully crossed within-subject 2x2 design. I have two factors, and each factor has two levels. It is a signal detection type of experiment. For each condition, it has 180 trials. So, total 180 * 4 = 720 trials for each participant.

I am confused about what the inputs for ng and nm in this situation are. According to the manual, ng seems to be the number of between-subject factors, and nm seems to be the levels of the within-subject factors.

Thus, should the parameters be ng = 1 and nm = 4, ng = 1 and nm = 2, or considering each trial is one measurement, ng = 1 and nm = 720?

Thank you for your help!

1 Answer

0 votes
by johnny (3.3k points)
selected by PL
Best answer
Currently, wp.rmanova does not support the analysis with two within-subject factors. It can conduct analysis for one within-subject factor or one within-subject factor and one between-subject factor.
by PL (150 points)
Thanks for the reply! It's very helpful!