Hi,
I have generated two different functional connectivity maps for two
different ROI-based seeds. These maps are based on group-average of the same
subjects (generated by using separate isxconcat-sess commands ), and now I
want to see the difference map. To do so, I used mris_calc as below.
Hi Shahin, it is not as simple as doing a subtraction of the cesvar
files. What you are trying to get is the expected variance of your
difference between the ces files (as a variance, it must be positive).
To get this you need
cesvardiff = (cesvar1+cesvar2)/(2^2)
The 2^2 is the number of
Thanks Doug. Just one related question. Should I also generate a new
ffxdof.dat file for this map? I assumed that ffxdof depends on the number of
subjects (session) and since number of subjects (sessions) is the same
between the two groups then I can use those values, generated by
It should be roughly the sum of the dofs of the individual subjects. Why
are you using a fixed-effects model?
doug
SHAHIN NASR wrote:
Thanks Doug. Just one related question. Should I also generate a
new ffxdof.dat file for this map? I assumed that ffxdof depends on the
number of
Do you suggest using random-effect model? Is there any problem with using a
fix-effect model (other than the fact that by using this model we can not
predict response of subjects outside our population)?
On Wed, Oct 19, 2011 at 3:07 PM, Douglas N Greve
gr...@nmr.mgh.harvard.eduwrote:
It should
If you don't care about extending your results beyond your sample, then
an FFx is fine.
doug
SHAHIN NASR wrote:
Do you suggest using random-effect model? Is there any problem with
using a fix-effect model (other than the fact that by using this model
we can not predict response of subjects
