Dear Amir,
The phase is indeed in radians so the values should be between -pi and
pi. If you average the phase using the 'vector (PLV)' option you will
get values between 0 and 1. If I compute the phase on the tutorial
example in SPM I get values distributed more or less uniformly between
-3.14 and 3.14 as expected.
Best,
Vladimir
On Fri, Dec 4, 2009 at 9:05 PM, Amir H Javadi <[log in to unmask]> wrote:
> Hi
> Dear Vladimir :-)
> Another question, this time about phase in Time-Frequency analysis. I'm
> confused with the phase analysis. I assume that the result is in Radian,
> right? OK. I wonder why I don't have a full range of angles from +90 degrees
> to -90 degrees? In none of the channels I have 90 degrees. In some of the
> channels the min and max are even -25' and +25'. It is almost symmetric in
> most of the channels, though. Am I missing something? How come I don't have
> for example +89 degrees? The data is for -200 ms before the stimulus onset
> to 3900 ms after the stimulus onset, with 512 samples/second. Time-Frequency
> analysis with 0.2 Hz frequency steps. No digital filter except one 1 Hz
> High-pass filter. Frequency range from 2-40 Hz.
> Again and again thanks for your attention.
> Have a good evening :-)
> Amir
>
>
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