[Homer-users] Short Separation in Developer's Version

[David Boas]

Most likely the units are mm and you need to use 15 for the rhoSD_SSThresh

The fact that the processing gets “stuck” when you use 15 probably indicates that it is busy calculating the short separation regression. Let me verify, you say it gets “stuck”, but it doesn’t crash?

What type of computer are you using? How big is your data set? 



> On Apr 29, 2015, at 11:49 AM, Rachel Mulheren <mulherrw at dukes.jmu.edu> wrote:
> 
> Hello,
> 
> I included 2 short separation channels (1 cm) in my probe and now that I am running the processing stream including the parameters for short separation, I get the following message: There are no short separation channels in this probe...performing regular deconvolution.
> Design matrix is VERY poorly scaled...(RCond=0.000000e+00), cannot perform computation
> 
> Eyeballing the HRF after running this processing stream, I am not seeing a difference with and without the short separation, so I am guessing that it was not extracted from the signal. 
> 
> Suggestions for what I might be doing incorrectly?
> 
> I am using Block Avg Short Sep
> trange -5 to 17
> gstd 1
> gms 1
> rhoSD_SSThresh 1.5
> 
> I have also tried with rhoSD_SSThresh 15 (in case there was a mix-up with mm and cm), but the processing starts and gets "stuck" on the short separation.
> 
> Thanks,
> 
> Rachel
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