Hi Sean,
> I have received a hard time from more than one reviewer for this approach,
> but I still like it.
Interesting to see that the obsession with the ANOVA framework persists.
> How do I code (A1B1-A1B2)-(A2B1-A2B2)? It seems I would need to use
> 3dcalc to make the (A1B1-A1B2) and (A2B1-A2B2) files before running the
> t-test. Is it valid to just subtract to data files like that (assuming each was
> created with the same 3dDeconvolve)? Is there another way to do it?
If you want to run 3dttest, yes you can simply use 3dcalc to get (A1B1-A1B2) and (A2B1-A2B2), or even (A1B1-A1B2)-(A2B1-A2B2) directly in the case of both A and B being within-subject factors. However, if you want to try 3dMEMA, you'd have to run 3dDeconvolve (and 3dREMLfit) to obtain (A1B1-A1B2) and (A2B1-A2B2) [or (A1B1-A1B2)-(A2B1-A2B2)] and their t-statistics.
Gang