Dear All
I am only getting started with SPM and I have some questions regarding the first analyses.
I have tried to analyze PET Data which is already normalized to MNI space and scaled to a reference region.
There are two independent groups with unequal sample size 23 versus 85 and I want to perform a simple t-test for independent samples (Controls versus HCS).
Here come the questions:
1. Is there any problem with unequal sample size using the t-test in SPM when one considers independent groups?
2. Is there any advantage in including the ancova function for subject for PET data as the data is already scaled? or more in general - in which case is it recommended to use the ancova function?
Kind regards
Anton
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