Note that this reference documentation is identical to the help that is displayed in MATLAB when you type “help ft_statfun_roc”.

  FT_STATFUN_ROC computes the area under the curve (AUC) of the
  Receiver Operator Characteristic (ROC). This is a measure of the
  separability of the data divided over two conditions. The AUC can
  be used to test statistical significance of being able to predict
  on a single observation basis to which condition the observation
  belongs.
  
  Use this function by calling one of the high-level statistics
  functions as
    [stat] = ft_timelockstatistics(cfg, timelock1, timelock2, ...)
    [stat] = ft_freqstatistics(cfg, freq1, freq2, ...)
    [stat] = ft_sourcestatistics(cfg, source1, source2, ...)
  with the following configuration option
    cfg.statistic    = 'ft_statfun_roc'
 
  Configuration options that are relevant for this function are
    cfg.ivar         = number, index into the design matrix with the independent variable
    cfg.logtransform = 'yes' or 'no' (default = 'no')
  
  Note that this statfun performs a one sided test in which condition "1"
  is assumed to be larger than condition "2".