Dear DCM experts,
I have a question on the matlab code of the routines 'spm_bireduce' and
'spm_bi_reduce'. In the older version of spm5 'spm_int' worked with
'spm_bi_reduce' in which the second order partial derivatives in M1 had a
factor 1/2 (line 186 of spm_bi_reduce.m). Now the new version of 'spm_int'
(line 65 of spm_int.m) works with 'spm_bireduce' to compute M1 (lines 82 and
97 of spm_bireduce.m), and there this factor is missing. I wonder which is
right.
Doesn't the 1/2 come from the Taylor-expansion, where the second order term
should have a factor 1/2 ?
Best wishes,
Volker Fischer
University of Regensburg, Germany.
http://www.psychologie.uni-regensburg.de/Greenlee/team/fischer/fischer.html
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