Hello,

I'm trying to run selxavg3-sess with FS v4.5 for an FIR analysis where each
trial is modeled as a separate condition.  The command works smoothly for
the majority of subjects, but for 2 different subjects, it exits with the
following error:

Saving X matrix to
/home/sam/fMRIDATA/samstudies/SoCo/SoCo10/bold/Logit/Xtmp.mat
XCond = 12220.6 (normalized)
ERROR: design is ill-conditioned
>> ------------------------------------------
ERROR: fast_selxavg3() failed\n

details:
I do not definite any contrasts, as I'm only running this command to
generate trial specific betas for a separate analysis.  Each trial lasts 18
seconds, followed by 4 seconds of fixation.  Here is what part of a
paradigm file looks like (the paradigm files are identical for all
subjects):

4 1 18 1
22 0 4 1
26 2 18 1
44 0 4 1
48 3 18 1
66 0 4 1
70 4 18 1
88 0 4 1
92 5 18 1
110 0 4 1
114 6 18 1
132 0 4 1
136 7 18 1
154 0 4 1

here are the analysis.cfg and .info files:
analysis analysis_name
TR         2
fsd        bold
funcstem   fmcsm4
tpexclude
parname    FIR_logit.par
designtype event-related
nconditions 96

-timewindow 20
-prestim 2
-acfbins 10
-fix-acf
-noautostimdur
-no-fsv3-st2fir
-no-fsv3-whiten
-polyfit 2
-TER 2
-nskip 0
-fwhm 0
-extreg mcextreg
-nextreg 3
-rescale 1000

the command which throws the error:
selxavg3-sess  -analysis analysis_name -s subject_name

The strange part for me is that this only seems to be a problem with a
couple subjects, despite the fact all the paradigm files are identical.
 After looking through the mailing archive, I tried playing around with the
prestim window, but even it if is = 0, there is 1 subject that exits with
an error when I run selxavg3-sess.  Do you know what might be going on?

Any guidance would be appreciated.

Thanks,
Sam
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