[FieldTrip] Cluster-based permutation test
emanuelvandenbroeke at hotmail.com
Thu Jun 19 14:11:31 CEST 2014
Dear Eric Maris or other fieldtrippers,
In my experiment (a 2x2x6 design) I want to test whether ERP waveforms are significant different between conditions. There is no a priori assumption about the effects.In this experiment I apply a somatosensory stimulus on both arms before and after an intervention on one arm. The somatosensory stimulus consists of 6 different intensities. So it is a within-subject design with 3 factors: Time (T0 and T1), Arm (intervention, control) and Intensity (6 different intensities).
I'm interested in the MAIN effect of INTENSITY, and the INTERACTION effects (TIME x ARM) and (TIME x ARM x INTENSITY).For the Interaction effect TIME x ARM, I first calculated difference-waves (postcontrol - precontrol and postintervention - preintervention) in Matlab en then applied the permutation test on these difference-waves to test whether the two arms are different. I hope this is correct?
But now my question, how to test the TIME x ARM x INTENSITY interaction? One possibility might be to calculate an ANOVA F statistic for this interaction effect (so perform a full factorial ANOVA) and perform the permutation test? Is this justified?
Very much thanks,Best wishes,Emanuel
-------------- next part --------------
An HTML attachment was scrubbed...
More information about the fieldtrip