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I am trying to replicate some event-related analysis in FSL that I did
with UCLA's AIR tools and I am getting an error that my design is rank
deficient.

Here is the setup:

I have seven types of questions A,C,L,M,R,T,U.  The TR is 4 and I
collected three volumes for each question (the question, the answer,
and the rest: q, a, r).

In the AIR tools, I specified three contrasts of C vs L & M, L vs. C &
M, and M vs C & L.  I included all three volumes (qar) in the contrast
design as follows:

C vs L&M:
                q       a       r
        C       -1      -1      8
        L       -1      -1      -1
        M       -1      -1      -1

L vs C&M
                q       a       r
        C       -1      -1      -1
        L       -1      -1      8
        M       -1      -1      -1

M vs C&L
                q       a       r
        C       -1      -1      -1
        L       -1      -1      -1
        M       -1      -1      8

The results fit substantive expectations beautifully.  But, I want to
take advantage of FSL's mixed effects abilities.

So, I specified nine EVs corresponding to Cq, Ca, Cr, Lq, La, Lr, Mq,
Ma, Mr.  And, I tried to set up the contrasts like I had in the AIR
tools.

C vs LM -1      -1      8       -1      -1      -1      -1      -1      -1
L vs CM -1      -1      -1      -1      -1      8       -1      -1      -1
M vs CL -1      -1      -1      -1      -1      -1      -1      -1      8

What am I doing wrong?  How do I replicate the AIR results in FSL?

I have verified that the custom 3 column files specifying the timing of
the EVs is correct.

Of course, I know that EV1, EV2, and EV3 are not independent, but I am
not sure how to replicate the AIR results without setting up the same
contrast.

By the time I get to the course in Marina del Rey, I will have a very
good understanding of FSL, I think.  But, since I have to have my data
analysis done for a deadline before the class, I appreciate your
indulgence with the ceaseless barrage of questions.

        Darren