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Hi, I just completed a mixed effects OLS analysis for the group mean of 18 first- level FEAT directory inputs. When I looked at the output, the higher-level COPE map was empty. I'm not sure what this means. There was a MaxZStat of 2.6, but no blobs of activation are visible on the map (presumably because so few voxels passed threshold). I'm puzzled about this because (a) most of the lower level COPES do show activation (b) I did not apply any masks to the data (c) my supervisor predicted that we'd see tons of activation :) I understand that this result may simply reflect the statistics that were applied at the higher-level (e.g. different degrees of freedom). But, I'm also concerned that something might have gone wrong with the analysis. Any thoughts on this? Thanks, Mona