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hi - some advise would be much welcome
this seems slighty different from previous posts.

I've got a sample of subjects and copes for task condition A and B.
now I want to assess whether A>B is modulated by task performance
so there is a different performance score for each subject on A and B
my design looks like - 
Note that behaviourally overall memory performance is superior in A than in B
 
I thought of something like this, 
rows: 1-4 are for the cope in condition A
rows: 5-8 are for the cope in condition B

Group    EV1  EV2  EV3  EV4  EV5  EV6      Performance EV
  subj1     1        1       1      0      0      0       0.7
  subj2     1        1       0      1      0      0       0.97
  subj3     1        1       0      0      1      0       0.85
  subj4     1        1       0      0      0      1       0.75
  subj1     1       -1       1      0      0      0       0.55
  subj2     1       -1       0      1      0      0       0..65
  subj3     1       -1       0      0      1      0       0.53
  subj4     1       -1       0      0      0      1       0.56


From prior posts it appears that I only need to multiply each performance score
by 1 or -1 (i.e adding +-signs accordingly for the performance EV)

then orthogonalise the Performance EV wrt EV2 (assume this is the same as overall demeaning
the performance EV, if only looking at covariation with this)

then specify contrast

0 0 0 0 0 0 +1 (to test for regions where A>B differences is modulated by performance EV
0 0 0 0 0 0 -1

my only concern is the fact that the behavioral mean for condition A is superior to the mean for conditions B,
so may reflect different things in quantity and quality
but guess this does not matter for the model?

cheers

david