New statistics
Robert Oostenveld
r.oostenveld at FCDONDERS.RU.NL
Wed Feb 7 21:43:37 CET 2007
Hi Vladimir,
On 30 Jan 2007, at 18:37, Vladimir Litvak wrote:
> I'm trying to switch from clusterrandanalysis to the new statistics
> routines. I made my best to configure the new routine in a way that
> would yield results identical to the old routine, but the results I
> get are very different. I put an example athttp://
> download.yousendit.com/7CE5F69B35B1C739 . Please check what's going
> on.
I looked in the script and data that you have sent and notice that
>> cfg.design
ans =
1 2 3 4 5 6 7 8 9 10
11 1 2 3 4 5 6 7 8 9 10 11
1 1 1 1 1 1 1 1 1 1
1 2 2 2 2 2 2 2 2 2 2 2
>> size(cfg.design)
ans =
2 22
and furthermore
>> size(freqavg{1}.powspctrm)
ans =
22 1 50 965
>> size(freqavg{2}.powspctrm)
ans =
22 1 50 965
So even though you seem to have 22+22=44 observations/subjects in the
data, you are only using 22 in the design to compute your statistical
contrast: You are actually computing the contast between the first 11
subjects in the first condition versus the second 11 subjects in the
first condition.
Your design probably should be
cfg.design = [
1:22 1:22 % subject index, runs from 1 to 22
(twice, since paired data)
1*ones(1,22) 2*ones(1,22) % condition number, is either 1 or 2
];
best regards,
Robert
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