Dear all,
I wonder how to decide which options to choose for "Covariates" in a 2-sample t-test of a VBM study.
Under "Interactions", there are 4 options:
- None
- Factor 1
- Factor 2
- Factor 3
Under "Centering", there are 8 options:
- Overall mean
- Factor 1 mean
- Factor 2 mean
- Factor 3 mean
- No centering
- User specified value
- As implied by ANCOVA
- GM
I'm going to use age and education level to be the covariates. What are Factor 1/2/3 ? What should I consider when deciding which options to choose for "Interaction" and "Centering"?
Thanks for any suggestions!
Best wishes,
Meikei
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