Dear SPMers,
Why does the correlation between two events increases as the temporal distance between them shortens? Does that mean that any two very closely spaced events can never be efficiently estimated? If we assume for the moment that the two events are very different conditions, why would they even be correlated? After all, we model those two conditions as separate regressors in the design matrix.
Relatedly, one of the points of jittering an efMRI design is to prevent correlation of successive points. But if the conditions are randomized, is correlation between successive points really an issue?
Thank you very much,
AJ
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