 |
 |
Dear SPM Group: I have SPM z score volumes on 5 individuals, each z score volume resulted from the identical contrast following the same experimental fMRI run. Each individual's z score volume has also been rethresholded. I want to create a group volume. Is it valid to just average across individuals and create a mean z score volume? Other methods such as summing the z volumes and dividing by square root of k have been suggested to me (k represents the number of z score maps, which in this case would be 5). Any thoughts? Thank you. Joe Tracy I want s on on five ind %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%