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Newsgroups: comp.soft-sys.matlab
Subject: Re: xcorr (cross-correlation)
Date: Mon, 21 Jul 2008 15:59:03 +0000 (UTC)
Organization: UC Berkeley
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I guess the question is:

By using c = xcorr(x,y,'coeff')

matlab generates standardize cross-correlation coefficients.
How to generate un-standardize cross-correlation
coefficients (range -1 to 1)?

The other 'options': 'biased', 'unbiased' and 'none' does
not seem to provide cross-correlation coefficients.

Do I need to do an extra calculation to obtain the
correlation coefficient when I ask for the 'none' option?

Thanks



"RV " <cyanokybus@yahoo.com> wrote in message
<g5ika7$6sg$1@fred.mathworks.com>...
> Hi,
> 
> I am using the function xcorr (cross-correlation)as follows:
> 
> c = xcorr(x,y,'coeff')
> 
> by using 'coeff' it normalizes the sequence so the
> autocorrelations at zero lag are identically 1.0. 
> 
> I would like to calculate the cross-correlation coefficient
> between vectors x and y at different lags but without
> normalization. 
> 
> The other 'options' 
> 
> 1) 'biased': Biased estimate of the cross-correlation
> function
> 
> or
> 
> 2) 'unbiased': Unbiased estimate of the cross-correlation
> function 
> 
> does not generate an output with the cross-correlation
> coefficient.
> 
> 
> Thanks for your help
> 
> 
> 
> 
> 
> 
> 
>