Hi - yes, this is unusually slow. You shouldn't have any problems with
RAM, because you have >40 inputs at second level, so FLAME will be being
run slice-by-slice. Could you send in design.gif from second level so we
can have a quick look at that.
In the meantime, you could try running FLAME (part 1 only) to check that
reasonable results are coming out.
Cheers, Steve.
On Tue, 4 May 2004, Sam Harris wrote:
> I have a question about how long a higher lever analysis can be reasonably expected to run. I
> recently set up a second level analysis on a dual G5 with 2.5 gigabytes of RAM, and after 36 hours
> it was still struggling to finish the the first COPE. At this rate, the analysis would have taken over
> two weeks to terminate. Is this even in the range of possibility for a valid design? Or is the
> problem necessarily in the brain of the user?
>
> The design came straight from the FSL documentation (Multi-Session & Multi-Subject [Repeated
> Measures -- Three Level Analysis]). We ran an event-related protocol on 14 subjects, 3 scans
> each, 170 volumes per scan. There were 12 contrasts done at the lower level. FLAME was run at
> both levels.
>
> Thanks in advance for your help.
> Best,
> Sam
>
Stephen M. Smith DPhil
Associate Director, FMRIB and Analysis Research Coordinator
Oxford University Centre for Functional MRI of the Brain
John Radcliffe Hospital, Headington, Oxford OX3 9DU, UK
+44 (0) 1865 222726 (fax 222717)
[log in to unmask] http://www.fmrib.ox.ac.uk/~steve
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