Hi Alex,

Yes.

For any contrast, you can simply build the components of each and subtract them. So, for this case:

0=(A-B)-(C-D)

if we distribute the subtract sign, we get:

0=A-B-C+D

resulting in the contrast vector:
1 -1 -1 1

===============================================================
Now, lets form the two contrasts separately, then subtract them.

0=A-B, gives the contrast vector 1 -1 0 0
0=C-D, gives the contract vector 0 0 1 -1

If we now subtract the C-D vector from the A-B vector, we get:
1 -1 -1 1

These are the two ways to generate any contrast and they both generate the same result.

Best,
Donald


Originally posted by Alex Rainer: