Dear AFNI experts,
I am looking for some advice to extracting beta values from specific brain area.
There are two questions, one is generating a mask, and the other one is extracting the beta values
(I’m new to this part, so forgive me if my question is too basic…)
Steps which I did:

Extract cluster, where I am interest in, from ANOVA result:
3dclust 1noneg 1thresh 0.05 prefix anova_cluster 3 500 ANOVA’[5]’ 
Create a mask1:
whereami mask_atlas_region CA_ML_18_MNIA:R:ins
(I used CA_ML_18_MNIA because I normalized the data into MNI space) 
Resample the mask:
3dresample dxyz 3.0 3.0 3.0 prefix resample3 input CA_ML_18_MNIA.ins.r+tlrc 
Create a mask2:
3dcalc prefix ROI a ‘resample3+tlrc’ b ‘anova_cluster+tlrc’ expr ‘(step(a)*b)’
Question1
When I process no.4, I got the FATAL ERROR message “dataset anova_cluster+tlrc differs in size [~voxels] from others [~]”
I’m not clear what I have to check… even I tried to search other materials.
( As I understood, I thought when we generate a mask, the values of the regions where we interested in are ‘1’, and the other parts are ‘0’.
Thus, I thought the voxel size should be same…)
Therefore, in this part, may I ask you that how can I solve the problem?
i. Create a mask from specific area (because I failed on generating the mask using two data…[above one…])
whereami mask_atlas_region CA_ML_18_MNIA:R:ins
ii. Resample the mask:
3dresample dxyz 3.0 3.0 3.0 prefix resample3 input CA_ML_18_MNIA.ins.r+tlrc
iii. Tried to extract beta values [actually… I’m not sure that this function is correct…]
3dmaskave mask resample3+tlrc stats.s10_REML+tlrc’[4]’
Question2
When I process no.iii, I also get the message that the “Input and mask datasets are not same dimensions!”
Also, I’m not clear whether it is right way to extract the beta values…
Thus, may I ask you that how can I solve this problem? (also extracting the beta values)
Thank you in advance.
DaWoon