thanks jesper,
is your suggested approach different mathematically from my approach A:
y = A1x1 + A2x2 + e
i.e. for your 3 column suggested approach is there still 2 regressors in the
GLM, one for mean vanilla effect and the other for the parametric
modulation? using the 3 column approach is the model treated differently
somehow than just plugging in 2 EV's?
thnx
v
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