cluster analysis and EEG channel information

[Hsu, Shen-Mou]

Just to clarify my query a bit more. I am trying to perform permutation tests on ERP data. The configuration was as below and the following error message was returned.

??? Undefined function or method 'conndef' for input
arguments of type 'double'.

Error in ==> clusterstat at 181
posclusobs = bwlabeln(tmp,
conndef(length(cfg.dim),'min'));

Error in ==> statistics_montecarlo at 394
  [stat, cfg] = clusterstat(cfg, statrand, statobs);

Error in ==> statistics_wrapper at 362
  [stat, cfg] = statmethod(cfg, dat, cfg.design);

Error in ==> timelockstatistics at 107
[stat] = statistics_wrapper(cfg, varargin{:});




load GA_F; load GA_N

cfg = [];
cfg.channel = {'all'};
cfg.latency = [0 0.5];

cfg.method = 'montecarlo';
cfg.statistic = 'depsamplesT';
cfg.clusteralpha = 0.05;
cfg.clusterstatistic = 'maxsum';
cfg.minnbchan = 2;
cfg.tail = 0;
cfg.clustertail = 0;
cfg.alpha = 0.05;
cfg.numrandomization = 100;

subj = 15;
design=zeros(2,2*subj);
for i = 1:subj
  design(1,i) = i;
end
for i = 1:subj
  design(1,subj+i) = i;
end
design(2,1:subj)        = 1;
design(2,subj+1:2*subj) = 2;

cfg.design   = design;
cfg.uvar  = 1;
cfg.ivar  = 2;


[stat_FvsN_HV] = timelockstatistics(cfg, GA_F, GA_N);
________________________________________
From: FieldTrip discussion list [FIELDTRIP at NIC.SURFNET.NL] On Behalf Of Hsu, Shen-Mou [shehsu at indiana.edu]
Sent: Tuesday, September 16, 2008 11:06 AM
To: FIELDTRIP at NIC.SURFNET.NL
Subject: [FIELDTRIP] cluster analysis and EEG channel information

Dear Users,


I preprocessed my EEG data using EEGLAB and then converted the data into the fieldtrip format using eeglab2fieldtrip. However, I noticed that in cfg.channel, there are only labels without any information about electrode locations. I was wondering if this is OK to run cluster analysis.  Besides, I also wondered how to specify the configuration-"cfg.channel" in this case.

Many thanks in advance,

Shen-Mou

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The aim of this list is to facilitate the discussion between users of the FieldTrip  toolbox, to share experiences and to discuss new ideas for MEG and EEG analysis. See also http://listserv.surfnet.nl/archives/fieldtrip.html and http://www.ru.nl/fcdonders/fieldtrip.

----------------------------------
The aim of this list is to facilitate the discussion between users of the FieldTrip  toolbox, to share experiences and to discuss new ideas for MEG and EEG analysis. See also http://listserv.surfnet.nl/archives/fieldtrip.html and http://www.ru.nl/fcdonders/fieldtrip.