standard error of complex data

[Karl Doron]

Hello,

I'd like to plot data from single channels/single subjects with error bars, so as 
to compare peak amplitudes across different experiment conditions.

In brief, I have Hilbert transformed data filtered from 8-12Hz. Then with a 
function I wrote, I pull all the trials for each condition and put them into a n X 
m matrix (trials x timepoints) for each channel.

The data are still complex because I have separate analyses for phase and 
amplitude. For amplitudes, I'm taking the evoked response by getting the 
mean of each timepoint across trials and then taking the magnitude (abs).

For the standard error, I am first getting the standard deviation by 

stdev=sqrt[ (norm(x)-mean(x)) ^2 ]

This produces a real number. For the standard error, would I then divide by 
the square root of N?

Thanks for any feedback,

Karl Doron
PhD. Candidate
UCSB

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