Freqstatistics Yields Zero Significant Clusters?

[Charles Cook]

Hi Eric,

We have modified the code based on your suggestions and I think we're very
close now. This is our most recent output:

-------------------------------------
reading power on 81 channels
not computing grand average, but keeping individual power for 11 subjects
not computing grand average, but keeping individual power for 11 subjects
selected 81 channels
selected 6 time bins
selected 4 frequency bins
Warning: PACK can only be used from the MATLAB command line.
> In fieldtrip\private\prepare_timefreq_data at 310
  In fieldtrip\private\statistics_wrapper at 206
  In freqstatistics at 132
  In CMCWM2_std81_junk_with at 144
Obtaining the electrode configuration from the configuration.
there are on average 83.0 neighbours per channel
using "statistics_montecarlo" for the statistical testing
using "statfun_indepsamplesT" for the single-sample statistics
constructing randomized design
total number of measurements     = 22
total number of variables        = 2
number of independent variables  = 1
number of unit variables         = 1
number of within-cell variables = 0
number of control variables      = 0
using a permutation resampling approach
repeated measurement in variable 1 over 22 levels
number of repeated measurements in each level is 1 1 1 1 1 1 1 1 1 1 1 1 1 1
1 1 1 1 1 1 1 1 
computing a parmetric threshold for clustering
estimated time per randomization is 0 seconds
found 2 positive clusters in observed data
found 1 negative clusters in observed data
using a cluster-based method for multiple comparison correction
the returned probabilities and the thresholded mask are corrected for
multiple comparisons
??? Assignment has more non-singleton rhs dimensions than non-singleton
subscripts

Error in ==> clusterplot at 91
    sigposCLM(:,:,iPos) = (posCLM == sigpos(iPos));

Error in ==> CMCWM2_std81_junk_with at 153
clusterplot (cfg, stat);

-----------------

We do keep running into this error with clusterplot. Which we have as follows:

cfg = [];
cfg.zlim = [-6 6];
cfg.alpha = 0.05;
clusterplot(cfg, stat);

It crashes on the last line. Does anyone have any ideas where we might be
going wrong here?

Cheers,

Charles

On Sat, 6 Jun 2009 09:04:43 +0200, Eric Maris <e.maris at DONDERS.RU.NL> wrote:

>Hi Charles,
>
>
>
>Although I'm not 100 percent sure that this is the cause of your problems,
>the way you specify the unit of observation is definitely wrong. You have 22
>units of observations (i.c., subjects) so the first row of cfg.design must
>be [1 2 ... 22; ... ]
>
>Also, did you check whether cfg.design is a 2-by-22 array? In the lines
>below, a semicolon seems to be missing.
>
>> cfg.design           = [1 2 3 4 5 6 7 8 9 10 11 1 2 3 4 5 6 7 8 9 10 11  %
>> subject number is 1-11 males and 1-11 females
>>                         1 1 1 1 1 1 1 1 1 1  1  2 2 2 2 2 2 2 2 2 2  2]; %
>> condition number with 1 being males and 2 being females
>>
>> cfg.uvar = 1;                                   % "subject" is unit of
>> observation
>> cfg.ivar = 2;                                   % "condition" is the
>> independent variable
>
>
>Good luck,
>
>
>dr. Eric Maris
>Donders Institute for Brain, Cognition and Behavior
>Center for Cognition and F.C. Donders Center for Cognitive Neuroimaging
>Radboud University
>P.O. Box 9104
>6500 HE Nijmegen
>The Netherlands
>T:+31 24 3612651
>F:+31 24 3616066
>E: e.maris at donders.ru.nl
>
>MSc Cognitive Neuroscience: www.ru.nl/master/cns/
>

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