Re: [Freesurfer] selxavg3-sess error "design is ill-conditioned"

2010-04-15 Thread Douglas N Greve
try it with a prestim of 0 Ben Letham wrote: > Yes, the paradigm came from optseq2 with a PSD window 0 19.2 0.4. > > Looking more into the details, it seems that the design is pretty > ill-conditioned, cond(Xn'*Xn) is 6.2e5, and the cut-off in > fast_selxavg3.m is 1e4. > > Like I said, the design

Re: [Freesurfer] selxavg3-sess error "design is ill-conditioned"

2010-04-15 Thread Ben Letham
Yes, the paradigm came from optseq2 with a PSD window 0 19.2 0.4. Looking more into the details, it seems that the design is pretty ill-conditioned, cond(Xn'*Xn) is 6.2e5, and the cut-off in fast_selxavg3.m is 1e4. Like I said, the design came from optseq2 and the cost/efficiency is the same as o

Re: [Freesurfer] selxavg3-sess error "design is ill-conditioned"

2010-04-15 Thread Douglas N Greve
Did you optimize the stimulus schedule with the idea that you would do sub-TR FIR estimation? Eg, you would have had to have run optseq2 with this in mind. If not, then you probably cannot do an FIR analysis. Instead, assume a shape (eg, -gammafit 2.25 1.25) doug Ben Letham wrote: > Hello, > >

[Freesurfer] selxavg3-sess error "design is ill-conditioned"

2010-04-15 Thread Ben Letham
Hello, I'm trying to run selxavg3-sess for an analysis with TER < TR, and it errors with "design is ill-conditioned". I searched the mailing list archive, and the only past problem of this sort that I found was associated with a faulty tpef file, which I am not using. The details: There is only o