Dear Johann,
I just tested group comprison results with different input in 'Variables.xlsx'.
One case is input with numbers (e.g. group 1 / group 2), the other is input with letters (e.g. group a / group b).
The results were quite different each other.
For group comparison, should I input only letters in 'Variables.xlsx' as the attached figure ?
Best regard,
Saske
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'Variables.xlsx' for group comparison
Hi Saske,
for group comparison it does not matter if you put in "letters", "group label names", or "numbers". The (parametric) results will always be the same. I belief that you may have used permutation testing to test for group differences. As this is based on random permutations it can be the case that the non-parametric p-values may differ from "run to run" (the actual group difference and the parametric p-values will remain the same as this is independent of the permutation testing). If non-parametric p-values differ substantially, it is an indicator that you did not perform sufficient permutations to obtain a reliable estimate. The same thing holds for network based statistics.
Best,
Johann
P.S.: I just substituted the group labels "male, female" in the variables sheet from the sample workspace with "0, 1" and parametric results are identical - please try this out if you have any doubts.
I tried what you replied.
First of all, thanks for your kind reply.
I tried what you mentioned.
I run with same parameter except for group labellings, but I got different results as the attached pdf file.
In addition to this problem, I wonder how I could get one-sample t-test result without any covariates(e.g., age, IQ).
I just only get a raw matrix of one specific group.
Best regard,
Saske