Yes... I am essentially trying to do mixed-effects ANOVA with subject modeled
as a random effect. Is it not possible to do this using an exchangeability
matrix in randomise?
On Tuesday, May 01, 2012 15:45:35 you wrote:
> I don't believe this is a valid design as you are violating the
> assumption of independence between observations.
>
> Best Regards, Donald McLaren
> =================
> D.G. McLaren, Ph.D.
> Postdoctoral Research Fellow, GRECC, Bedford VA
> Research Fellow, Department of Neurology, Massachusetts General Hospital
> and Harvard Medical School
> Website: http://www.martinos.org/~mclaren
> Office: (773) 406-2464
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> On Tue, May 1, 2012 at 2:42 PM, Benjamin Kay <[log in to unmask]> wrote:
> > I have a group-level design where each subject has an activation map from
> > 1, 2, or 3 identical sessions. I want to use randomise to test for
> > significant differences in the activation map between groups.
> >
> > I created a design.grp file that looks something like this:
> > /NumWaves 1
> > /NumPoints 192
> > /Matrix
> > 1
> > 1
> > 2
> > 3
> > 4
> > 5
> > 6
> > 6
> > 6
> >
> > And so on, for 192 rows and 99 subjects. My design.mat file has the same
> > number of rows (192) and 7 columns. The first contrast in design.con is:
> > 1 -1 0 0 0 0 0
> >
> > When I run randomise with '-m design.mat -t design.con -e design.grp',
> > randomise says:
> > 1 permutations required for exhaustive test of t-test 1
> > Doing all 1 unique permutations
> >
> > I would think that more than one permutation is possible/advisable for
> > this contrast. How should I be setting up my exchangeability matrix?
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