Dear List,
Our design is a paired t-test (13 subjects) with a covariate (its value
is the same in both images of the same subject). We would like to test
the hypothesis of zero regression slope against the alternative of a
positive slope with the following contrast (value 1 in the column of the
covariate):
zeros(1,13) 1 0 0
But the contrast is invalid. What are we doing wrong?
Thanks a million
Verónica
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