[Eeglablist] Calculating ERSP in STUDY design using one whole condition as baseline

[Christian Scharinger]

Dear eeglab users,

one further question, maybe someone has any suggestions:
I have run an experiment with 4 different conditions. I would now like 
to define one of these conditions as baseline against which the 
remaining three conditions are compared, i.e. their ERSPs are calculated.

In other words: when calculating ERSPs in a STUDY design I would like to 
define a whole condition as baseline for other conditions.

Is there any "easy" way to do this?

In the std_ersp function I found the argument:
'powbase'    - [ncomps,nfreqs] optional input matrix giving baseline 
power spectra (not dB power, see >> help timef). For use in repeated 
calls to timef() using the same baseine {default|[] -> none; data 
windows centered before 0 latency}

I guess this might be the argument where I could define my "common 
baseline"? But I didn't figure out what kind of matrix the 'powbase' 
argument does expect and how to calculate this matrix in an "easy" way.

I would be very glad about any suggestions!

Best,
Christian


-- 
Christian Scharinger, M.A.

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