Hi Rachel,

My 3dmerge results are exactly the same as the 3dclust results.

How are you evaluating whether they are the same or different?
Perhaps a good method would be to run 3dclust on your 3dmerge
dataset.

Suppose your 3dmerge dataset name is merge_result+orig. Run
the same 3dclust command on merge_result+orig, except set the
threshold to 0.01 and the minimum volume to 10, say. It should
give you the same output as from your z_stats dataset.

You could also count the number of non-zero voxels in it to be
sure the equivalent volume equals the total volume output by
3dclust.

------------------------------------------------------------
3dclust -1thresh 0.01 5.6 2 merge_result+orig
3dmaskave -mask merge_result+orig merge_result+orig
------------------------------------------------------------

If you multiply the number of voxels output by 3dmaskave by the
volume per voxel (which is 8 mm^3), you should get the total
volume reported by 3dclust.

- rick