You need the df and the p-value, but he p-value can be derived from the Z-score. So all you really need is the df. Note that the probabilities are the lower tail probabilities and not the upper tails.
This formula should work
spm_invTcdf(spm_Ncdf(Z,0,1),df)
Best Regards, Donald McLaren ================= D.G. McLaren, Ph.D. Research Fellow, Department of Neurology, Massachusetts General Hospital and
Harvard Medical School Postdoctoral Research Fellow, GRECC, Bedford VA Website: http://www.martinos.org/~mclaren Office: (773) 406-2464 =====================
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On Fri, Nov 8, 2013 at 12:49 AM, Michael King <[log in to unmask]> wrote:
Hi,
I would like to calculate the t-statistic from a reported z statistic for an activated voxel. What information will I need to perform this (df, p value etc)?
