I have a problem with a contrast. I would like to make the comparison A>(B-C) with equal weight between conditions. I think that the best solution is the contrast [1 -0.5 0.5]. However the sum of elements of this contrast is different from 0 (=1 in this case).
How is it important that the sum of contrast arguments equal to 0 ? If yes, why is it the case ? If you are not agree with this contrast proposition, how would you do this comparison ?
Thanks a lot
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