afni fdr q method

Hi AFNI team,

In the afni result stats.$subj* files, we can always see the q and p values and set them as the threshold.

My question is: what’s the q value fdr procedure used here? Is it Benjamini-Hochberg procedure or is it something else? Need the information for the paper method section.

Thank you!


Hi, LW-

I think this page describes it all:


And note that the default processing by does not mask at the single subject level (aside from the extents mask), so those FDR values will not be so accurate. For more accuracy, run 3dFDR with a brain mask.

  • rick

The output of “3dFDR -help” has some explanation. The method is the basic B-H technique (voxel-wise, not cluster-wise), with an adjustment for estimated fraction of “true negatives”. As Rick says, a mask is important to cast out non-brain voxels from the considerations.

Thank you, this answered my questions!