Hi Jonas
I downloaded this and it looks extremely useful - Thank you!
Harriet
-----Original Message-----
From: Jonas Kaplan <[log in to unmask]>
To: [log in to unmask]
Date: Thu, 28 Apr 2005 09:24:51 -0700
Subject: Re: [FSL] average times series plots for each EV
Hi,
I have written a perl script to pull out the average value for each
timepoint relative to each EV which might be useful to you...
It doesn't work on the output of featquery, but if you've specified
your EVs in three column format it will get the appropriate data points
from filtered_func_data
within a mask or set of masks, and you can choose a time window around
each EV. Interpolation is linear, not spline, but it makes for some
nice graphs...
you can get it from http://www.jonaskaplan.com/peate.html
--
Jonas Kaplan , Ph.D.
Assistant Research Psychologist
Ahmanson-Lovelace Brain Mapping Center
University of California, Los Angeles
Los Angeles, CA 90095
Phone: (310) 794-4964
http://www.jonaskaplan.com
On Apr 28, 2005, at 5:06 AM, HA Allen wrote:
> Thanks Steve
>
> I think I am starting to get somewhere, however, i still have
> questions:
> What function is fitted to the data in the plots in the webpages? Is
> it different from the model used for the stats (and used to generate
> the information in the third and fourth column of the peristimulus
> text file)?
>
> If the second column of the peristimulus text file is the data, can't
> I just get the average for each timepoint by averaging the values (ie
> second column) for each time point (eg all the instances where column
> 1=1.1 etc)? From your answer this sounds to be wrong, but i dont
> understand why.
>
> Thank you very much for your help
>
> Harriet
>
> -----Original Message-----
> From: Stephen Smith <[log in to unmask]>
> To: [log in to unmask]
> Date: Wed, 27 Apr 2005 19:19:06 +0100
> Subject: Re: [FSL] average times series plots for each EV
>
> Ah yes - apologies for the confusion, my fault: in the text file
> associated with the peristimulus plots, each line contains a different
> original data timepoint: the first column is the "peristimulus time"
> (time
> relative to the start of each event), the second column is the data,
> the
> third column is the partial model fit for the contrast, the fourth
> column
> is the full model fit and the fifth column is the reduced data for the
> contrast. So yes as you go down the file you run through the timings
> for
> each different event (of the same type). In order to get an average
> shape
> you would need to either fit some function to the data (as the plots in
> the report webpages do) or reconstruct the shape from the model and the
> PEs. Hope this helps?
>
> Cheers, Steve.
>
>
>
> On Wed, 27 Apr 2005, HA Allen wrote:
>
>> Thanks Steve
>>
>> Oh dear, I think I have misunderstood something basic somewhere. I
>> dont
>> think I really understand what is written in the output raw data text
>> file underlying the peristimulus plots.
>>
>> My confusion comes from the entries in the first column of the 5
>> column
>> text file. I understand this to be time, as show on the x axis of the
>> plot. There are multiple entries of each time value (e.g. there are
>> several rows that have e.g. 1.1 in the first column). What does this
>> mean? Does each represent a separate trial/event? Or not?
>>
>> Thank you
>>
>> Harriet
>>
>
> --
> 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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