Path: news.mathworks.com!not-for-mail
From: "Andrew Palmer" <apalmer28@googlemail.com>
Newsgroups: comp.soft-sys.matlab
Subject: Re: xcorr (cross-correlation)
Date: Tue, 15 Jul 2008 18:49:02 +0000 (UTC)
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"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
> 
> 
> 
> 
> 
> 
> 
> 

I believe there is another option: 
3) 'none':  use the raw, unscaled cross-correlations