maximum statistic correction for mulitple comparisons

Robert Oostenveld r.oostenveld at FCDONDERS.RU.NL
Tue Apr 10 12:59:37 CEST 2007

Hi Andrew,

On 5 Apr 2007, at 17:34, Andrew Smart wrote:
> when using the maximum statistic correction for multiple
> comparisons what
> are the values on the colorbar and in the image? are they the
> corrected
> p-values?

The values that you get in the field "stat.prob" when you do either
one of
   stat = freqstatistics(cfg, freq)
   stat = timelockstatistics(cfg, timelock)
   stat = sourcestatistics(cfg, source)
and with cfg.correctm=yes are indeed corrected p-values. The
functions will also print the following on your screen
   "using a maximum-statistic based method for multiple comparison
   "the returned probabilities and the thresholded mask are corrected
for multiple comparisons"

> also, i cannot find the cfg.correctm documented anywhere, on the
> index or in
> the scripts. is there a documentation for this?

There is no more documentation on them than this single line in
%   cfg.correctm         = apply multiple-comparison correction,
'no', 'max', cluster', 'bonferoni', 'holms', 'fdr' (default = 'no')

Someone here in Nijmegen is currently rewriting the randomization
statistics tutorial, I will ask him whether he can add some
information on these options.

best regards,

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