Hello!
I have been working for a while now trying to get cluster thresholds by using 3dClustSim for a 3dLME group analysis I ran, but the thresholds I am getting still seem strangely low. For a wholebrain with functional data smoothed at 6 with 3dBlurToFWHM, at p threshold of .005, alpha of .05, NN2, bi-sided, it recommends a threshold of 16.3 (voxel size 3.125 mm x 3.125 mm x 3.125 mm). I am calculating my ACF values using 3dFWHMx and the input file is the residuals I collected from the 3dLME analysis I ran (which was supported as an option here: [
afni.nimh.nih.gov]). Below are the ACF values output:
0 0 0 0
0.572146 2.46819 7.35051 6.73157
Do you have any ideas about what I might be missing? Please know if I can add additional information to help get to the bottom of this.
Thank you,
Heather