clusterrand electrode neighbours

Stephan Bickel stephan.bickel at ANATOM.UNIZH.CH
Thu May 25 20:30:50 CEST 2006


Hi,

I try to apply clusterrandanalysis to time-frequency data I exported from
BESA.But I seem to have a problem with the specifications of neighbouring
electrodes. 
After applying clusterrandanalysis I get several significant clusters in the
same time-frequency range in neighbouring electrodes, i.e. one cluster for
each electrode in that range. I assumed that they should be collected to one
one cluster if the effect is in the same range and region? 

Here is what I tried:

elec = read_fcdc_elec('27mtg.sfp');       % the exported BESA coordinates

cfg=[];
cfg.statistic  = 'depsamplesT';
cfg.alphathresh = 0.05;
cfg.makeclusters = 'yes';
cfg.clusterteststat = 'maxsum';
cfg.onetwo = 'twosided';
cfg.alpha = 0.05;
cfg.nranddraws = 1000;
cfg.channel = 'all';                
cfg.neighbourdist = 0.04;           % I also tried 0.05 with the same result
cfg.latency = 'all';
cfg.elec   = elec;
[stat] = clusterrandanalysis(cfg,fileB,fileA);

I also tried the analysis with manually defined neighbours, but received the
same result. 
I attached the elec variable with the coordinates. 

Thank you very much for your help,

Stephan



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