How to Set thr in the image caculator?

Submitted by waynesupe126 on

Dear Dr Yan

         I have several problem which confuse me .

         1. How to set the thr in the image caclator. I gonna set a mask use the expression, (i1<thr)+(i2<thr). I have no idea about the definition of thr. I had ever used the number of Voxels(alpha sim correction) and thr in Viewer. But it doesn't work.

        2.It confuse me that there are many noises in the blank region. 

        3.How to use the results of the Permutation Test? There are 3 group images date, vox_tstat/vox_fwep, tfce_tstat/tfce_fwep,and clustere_stat/clustere_fwep in the floder. In the course of dpabi, you said you would perfer to use tfce_fwep in setting the thr, but you didn't tell us the overlay file you choose.Isn't it to use the file ,tfce_tstat ?

     4.In the DPARSFA, I am not sure if It process the step in doing  Extract ROI time course after doing filter.

         Best

          Wayne 

       

Setting of Dparsf

YAN Chao-Gan

Fri, 02/10/2017 - 07:48

1. You can set Z > 3.1 (which is one tailed p < 0.001) for a Z map.

2. It's normal. This is why people like cluster based multiple comparison correction, which removes the dots.

3. Watch the course and see: http://wiki.rfmri.org/PermutationTest

4. After filtering.