fourierspectra and freqstatistics

[jan-mathijs schoffelen]

Dear Jasper,

> Can I input these fourier spectra directly to freqstatistics or
> should I convert the fourierspectrum first to a powerspectrum (I
> assume this could be done by taking abs(fourierspectrum).^2 and
> then averaging over tapers for every trial ) ?

I suspect that you cannot directly put fourierspectra  into
freqstatistics when you want to perform a T-test on the power. I
always throw the frequency data at freqdescriptives (with
cfg.keeptrials = 'yes'); this should give you single trial power
spectra. Then you can use the 'montecarlo' or 'analytic' method for
statistical inference. You can indeed also compute the variance in
freqdescriptives, but I am not sure how to get to a T-value using
fieldtrip there. At least you won't get there using the 'statfuns'.

Best,

JM

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