Re: Should I standardize the time series before using "specx_anal" ?

From: Dennis Shea <shea_at_nyahnyahspammersnyahnyah>
Date: Thu, 8 Feb 2007 10:15:07 -0700 (MST)

> I found that the spectrum plot will be changed
> greatly if I standardize the time series before
> using "specx_anal".
>
> I am a little puzzled on it. Is it necessary to
> do a standardization at first when we analyze the spectrum ?
>
> ( I analyze the 102-yrs precipitation datas , all data ,
> script and plots have been uploaded to ftp://cgd.ucar.edu/incoming/ )
-------------

Standardization normalizes the data [variance=1].

The point of spectral analysis is to look at which frequency
bands have the most variance and are they significant
either physically or statistically.

Don't normalize before doing spectral analysis.

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Received on Thu Feb 08 2007 - 10:15:07 MST

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