Dear DCM-experts,
I am experimenting with the estimator of DCM (spm_nlsi_GN.m) and I am
wondering what is the best way to change the starting position of the EM
while preserving the priors for the estimation.
I implemented the following hack. It would be great if anybody could
confirm that this is correct. In spm_nlsi_GN.m I added the following
lines just in front of the main loop
...
% EM
%==========================================================================
C.F = -Inf; % free energy
v = 0; % log ascent rate
dFdh = zeros(nh,1);
dFdhh = zeros(nh,nh);
%%%%%%%%%%%%%%%%%%%%%%%%%
% Change start position
load newStart # load the variable 'start'
Ep = start; # changes the MAP
p = [V'*(spm_vec(start) - spm_vec(M.pE)); Eu]; # adjusts
the deviation from the prior expectations
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
% end of Change start position
for k = 1:64
% time
%----------------------------------------------------------------------
Ti = clock;
....
Thank you,
Martin
--
SPM for programmers
http://spm.martinpyka.de
