Hi Thomas,

Regarding your analysis with 3dRegAna, do the age groups and two sexes have roughly the same average value of the explanatory variable A? What effects are you testing?

> Secondly, I have a separate dataset consisting of three groups: controls, patient responders,
> and patient nonresponders. I would like to find areas that discriminate between the groups in
> that nonresponders<controls<responders, and also in the opposite direction. Is the best
> choice to attack this question to run ttests on each pair of groups, determine their pairwise
> significance levels, and run a conjunction in which both nonresponders<controls significantly
> and controls<responders significantly, and vice versa? Or, is there a more sophisitcated way
> to address this?

With only three groups, pairwise comparison (followed by conjunction analysis) is the best way to go.

Gang