[Ifeffit] CORRELATION MATRIX IN IFEFFIT

[Renato Canha Ambrosio]

Hi folks


I'm need to explore more the correlation matrix R(ij)given by ifeffit since 
my fit several variables are ajusted (the number is far bellow the number of 
independent data points).
In my MACRO, the command correl (@all, @all, print) permit to obtain the 
correlation matrix.
So I have some questions about the calculation of correlations (rij):
1) Is  the correlations(rij) calculated in ifeffit the sample linear 
correlation which measures the linear dependence between two vectos (in this 
sense, I'm thinking the term vector as a nx1 matrix in which n corresponds 
to the sample size - perhaps the number of fit iteractions)? If so, can I 
use a conventional hypothesis test like t (t = rij*sqrt[(n-1)/(1-rij**rij)] 
and how many degress of fredon can I consider to fint the t score on the 
table of t student distribution?

2) As I need to explore more the correlation matriz I would like to know if 
someone uses principal component analysis on Rij or some other chemometric 
approach.

Thank you very much

Renato Canha Ambrosio


--
Open WebMail Project (http://openwebmail.org)


---------- Original Message -----------
From: ifeffit-request at millenia.cars.aps.anl.gov
To: ifeffit at millenia.cars.aps.anl.gov
Sent: Wed, 22 Mar 2006 12:00:17 -0600
Subject: Ifeffit Digest, Vol 37, Issue 6

> Send Ifeffit mailing list submissions to
> 	ifeffit at millenia.cars.aps.anl.gov
> 
> To subscribe or unsubscribe via the World Wide Web, visit
> 	http://millenia.cars.aps.anl.gov/mailman/listinfo/ifeffit
> or, via email, send a message with subject or body 'help' to
> 	ifeffit-request at millenia.cars.aps.anl.gov
> 
> You can reach the person managing the list at
> 	ifeffit-owner at millenia.cars.aps.anl.gov
> 
> When replying, please edit your Subject line so it is more specific
> than "Re: Contents of Ifeffit digest..."
> 
> Today's Topics:
> 
>    1. GeO2 (Santiago J.A. Figueroa)
> 
> ----------------------------------------------------------------------
> 
> Message: 1
> Date: Tue, 21 Mar 2006 17:06:45 -0300
> From: "Santiago J.A. Figueroa" <figueroa at inifta.unlp.edu.ar>
> Subject: [Ifeffit] GeO2
> To: <ifeffit at millenia.cars.aps.anl.gov>
> Message-ID: <004701c64d23$00f973a0$8c01010a at NEVERMIND>
> Content-Type: text/plain; charset="iso-8859-1"
> 
> Hi all,
> 
> Anyone out there have spectra for a GeO2 standard?
> 
> Thanks!
> 
> Lic. Santiago J. A. Figueroa
> Instituto de Investigaciones Fisicoquímicas
> Teóricas y Aplicadas (INIFTA)
> Fac. de Cs. Exactas.
> Universidad Nacional de La Plata
> Diag. 113 y 64 
> C.C.16 suc.4 (1900) La Plata 
> TEL: (0221) 425 7430 interno: 144
> FAX: (0221) 425 4642
> WEB: www.inifta.unlp.edu.ar
> 
> -------------- next part --------------
> An HTML attachment was scrubbed...
> URL: 
> 
http://millenia.cars.aps.anl.gov/pipermail/ifeffit/attachments/20060321/4f60c
8ad/attachment-0001.html
> 
> ------------------------------
> 
> _______________________________________________
> Ifeffit mailing list
> Ifeffit at millenia.cars.aps.anl.gov
> http://millenia.cars.aps.anl.gov/mailman/listinfo/ifeffit
> 
> End of Ifeffit Digest, Vol 37, Issue 6
> **************************************
------- End of Original Message -------