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reference:ft_freqstatistics [2018/08/23 14:43] (current)
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 +=====  FT_FREQSTATISTICS =====
 +
 +Note that this reference documentation is identical to the help that is displayed in MATLAB when you type "help ft_freqstatistics"​.
 +
 +<​html><​pre>​
 +  <a href=/​reference/​ft_freqstatistics><​font color=green>​FT_FREQSTATISTICS</​font></​a>​ computes significance probabilities and/or critical
 +  values of a parametric statistical test or a non-parametric permutation
 +  test.
 + 
 +  Use as
 +    [stat] = ft_freqstatistics(cfg,​ freq1, freq2, ...)
 +  where the input data is the result from <a href=/​reference/​ft_freqanalysis><​font color=green>​FT_FREQANALYSIS</​font></​a>,​ <a href=/​reference/​ft_freqdescriptives><​font color=green>​FT_FREQDESCRIPTIVES</​font></​a>​
 +  or from <a href=/​reference/​ft_freqgrandaverage><​font color=green>​FT_FREQGRANDAVERAGE</​font></​a>​.
 + 
 +  The configuration can contain the following options for data selection
 +    cfg.channel ​    = Nx1 cell-array with selection of channels (default = '​all'​),​
 +                      see <a href=/​reference/​ft_channelselection><​font color=green>​FT_CHANNELSELECTION</​font></​a>​ for details
 +    cfg.latency ​    = [begin end] in seconds or '​all'​ (default = '​all'​)
 +    cfg.frequency ​  = [begin end], can be '​all' ​      ​(default = '​all'​)
 +    cfg.avgoverchan = '​yes'​ or '​no' ​                  ​(default = '​no'​)
 +    cfg.avgovertime = '​yes'​ or '​no' ​                  ​(default = '​no'​)
 +    cfg.avgoverfreq = '​yes'​ or '​no' ​                  ​(default = '​no'​)
 +    cfg.parameter ​  = string ​                         (default = '​powspctrm'​)
 + 
 +  If you specify cfg.correctm='​cluster',​ then the following is required
 +    cfg.neighbours ​ = neighbourhood structure, see <a href=/​reference/​ft_prepare_neighbours><​font color=green>​FT_PREPARE_NEIGHBOURS</​font></​a>​
 + 
 +  Furthermore,​ the configuration should contain
 +    cfg.method ​      = different methods for calculating the significance probability and/or critical value
 +                     '​montecarlo' ​   get Monte-Carlo estimates of the significance probabilities and/or critical values from the permutation distribution,​
 +                     '​analytic' ​     get significance probabilities and/or critical values from the analytic reference distribution (typically, the sampling distribution under the null hypothesis),​
 +                     '​stats' ​        use a parametric test from the MATLAB statistics toolbox,
 +                     '​crossvalidate'​ use crossvalidation to compute predictive performance
 + 
 +    cfg.design ​      = Nxnumobservations:​ design matrix (for examples/​advice,​ please see the Fieldtrip wiki,
 +                       ​especially cluster-permutation tutorial and the '​walkthrough'​ design-matrix section)
 + 
 +  The other cfg options depend on the method that you select. You
 +  should read the help of the respective subfunction FT_STATISTICS_XXX
 +  for the corresponding configuration options and for a detailed
 +  explanation of each method.
 + 
 +  To facilitate data-handling and distributed computing you can use
 +    cfg.inputfile ​  ​= ​ ...
 +    cfg.outputfile ​ =  ...
 +  If you specify one of these (or both) the input data will be read from a *.mat
 +  file on disk and/or the output data will be written to a *.mat file. These mat
 +  files should contain only a single variable, corresponding with the
 +  input/​output structure.
 + 
 +  See also <a href=/​reference/​ft_freqanalysis><​font color=green>​FT_FREQANALYSIS</​font></​a>,​ <a href=/​reference/​ft_freqdescriptives><​font color=green>​FT_FREQDESCRIPTIVES</​font></​a>,​ <a href=/​reference/​ft_freqgrandaverage><​font color=green>​FT_FREQGRANDAVERAGE</​font></​a>​
 +</​pre></​html>​