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reference:ft_statfun_diff_itc [2018/08/23 14:43] (current)
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 +=====  FT_STATFUN_DIFF_ITC =====
 +
 +Note that this reference documentation is identical to the help that is displayed in MATLAB when you type "help ft_statfun_diff_itc"​.
 +
 +<​html><​pre>​
 +  <a href=/​reference/​ft_statfun_diff_itc><​font color=green>​FT_STATFUN_DIFF_ITC</​font></​a>​ computes the difference in the inter-trial coherence between
 +  two conditions. The input data for this test should consist of complex-values
 +  spectral estimates, e.g. computed using <a href=/​reference/​ft_freqanalysis><​font color=green>​FT_FREQANALYSIS</​font></​a>​ with method=mtmfft,​ wavelet
 +  or mtmconvcol.
 + 
 +  The ITC is a measure of phase consistency over trials. By randomlly shuffling the
 +  trials ​ between the two consitions and repeatedly computing the ITC difference, you
 +  can test the significance of the two conditions having a different ITC.
 + 
 +  A difference in the number of trials poer condition will affect the ITC, however
 +  since the number of trials remains the same for each random permutation,​ this bias
 +  is reflected in the randomization distribution.
 + 
 +  Use this function by calling the high-level statistic functions as
 +    [stat] = ft_freqstatistics(cfg,​ freq1, freq2, ...)
 +  with the following configuration options
 +    cfg.method ​   = '​montecarlo'​
 +    cfg.statistic = '​diff_itc'​
 +  and optionally the options
 +   ​cfg.complex ​   = '​diffabs'​ to compute the difference of the absolute ITC values (default), or
 +                    '​absdiff'​ to compute the absolute value of the difference in the complex ITC values.
 +  ​
 +  For this specific statistic there is no known parametric distribution,​ hence the
 +  probability and critical value cannot be computed. This specific statistic can
 +  therefore only be used with cfg.method='​montecarlo'​. If you want to do this in
 +  combination with cfg.correctm='​cluster',​ you also need either
 +  cfg.clusterthreshold='​nonparametric_common'​ or '​nonparametric_individual'​.
 + 
 +  See <a href=/​reference/​ft_freqstatistics><​font color=green>​FT_FREQSTATISTICS</​font></​a>​ and <a href=/​reference/​ft_statistics_montecarlo><​font color=green>​FT_STATISTICS_MONTECARLO</​font></​a>​ for more details
 +</​pre></​html>​