Hi all,
I have a very basic question:
I am trying to compare IC maps of two groups of controls and patients and I was wondering whether I should perform a one-tailed t-test (SPM's default ttest) or a two-tailed t-test? Also, is selecting the two contrasts of [1 -1] and [-1 1] in "contrast manager" and using "Conjunction" in the "Results" panel, equivalent to a two-tailed t-test or using a F-contrast of [1 -1] ? Also, I have the same question of whether performing one-tailed or two-tailed in case of performing t-test in each group separately (ie. one sample).
Thanks,
-Mojdeh
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