Hi list,
I have a quick question about an old post I found about changing t
scores to z scores
This post:
http://www.jiscmail.ac.uk/cgi-bin/wa.exe?A2=ind04&L=SPM&P=R376942&I=-3
Suggests using this command for SPM2:
z_score = spm_t2z(t_score, degrees_of_freedom)
t_score: comes from your SPM map
degrees_of_freedom: at the bottom right of the SPM map
When I try this in SPM for large t-scores, I get a different Z score
than the table that is created when I hit the Volume button. For example
T = 9.84
Z in table = 7.79
Z from command above = 7.33
I am guessing that SPM5 uses a different m file to get the z scores that
come out in the table. Does anyone know if that's true, and if so, what
file it is?
Thanks!
Erin
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