On 1/23/2021 3:00 PM, Meike Hettwer wrote:
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Dear Freesurfer experts,
I ran a glm analysis a while back and corrected for MC using the glm-fit_sim --cache option / Monte Carlo simulation. I now saw that the AlphaSim algorithm this is based on is not recommended anymore (*MailScanner has detected a possible fraud attempt from "secure-web.cisco.com" claiming to be* https://afni.nimh.nih.gov/pub/dist/doc/program_help/AlphaSim.html). Instead, it suggests using 3DClustSim.
- Does that mean the Monte Carlo simulation as it is implemented in
FreeSurfer does not allow for valid analyses / MC corrections anymore?
No
- Is 3DClustSim implemented in Freesurfer? And if not, would I need
to export the FreeSurfer files as a volume (i.e. 3D) file and analyse it externally?
I don't know what 3DClustSim does.
What would you recommend? (My analysis is a regression analysis for one group, so the design matrix is not really suitable for a permutation).
You can use permutation for this using sign-flipping
Thanks in advance,
Meike
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