SPMers,
I have employed a multiple regression model for a second level analysis in
SPM2 (the regression option without a constant), with two covariates (c1
and c2), and an appropriate contrast image for each participant. I have
three questions:
1. Does this model report standardised regression co-efficients?
2. To look at the effect of c1, without regressing out the effect of c2, I
have entered a contrast vector of [1 0]. Should this contrast report the
same effects as a simple correlation?
3. To obtain the effects of c1 with c2 regressed out, should I enter a
contrast vector of [1 -1], or [1 1]?
Thanks in advance,
Matt.
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