Reply To: MEA in mother-father-infant interactions

[fabian]

I would do it on the total sample.
Do you expect large differences between separate groups?

A good way to reach an empirically-based solution is to carefully look at the lagplot (and/or the heatmaps).
These graphical displays should give you a good insight into the decision on separate or group-level pre-processing.
Cheers, Fabian