Sixpack, PCA controll, "IND" column
Hello, does anyone know the meaning of the IND column in the PCA controll field of sixpack (version 0.63)? I did not found a hint in the sixpack documentation. Best regards Joerg
This is the factor indicator function. Its minimum can be used to indicate the correct number of meaningful factors. There's an explanation here: http://www.vub.ac.be/fabi/multi/pcr/chaps/chap6.html For more information, see Malinowski's book Factor Analysis in Chemistry. -Leslie -----Original Message----- Hello, does anyone know the meaning of the IND column in the PCA controll field of sixpack (version 0.63)? I did not found a hint in the sixpack documentation. Best regards Joerg ** Leslie L. Baker, Ph.D. Department of Plant, Soil and Entomological Sciences University of Idaho Moscow, ID 83844-2339 208-885-9239 http://scholar.google.com/citations?user=ejpH5p0AAAAJ
That book is out of print and hard to get. You should refer to later papers. The IND function is not necessarily robust. It's not rigorously derived, but is sort of empirical. mam On 6/21/2012 9:20 AM, Baker, Leslie wrote:
This is the factor indicator function. Its minimum can be used to indicate the correct number of meaningful factors.
There's an explanation here: http://www.vub.ac.be/fabi/multi/pcr/chaps/chap6.html
For more information, see Malinowski's book Factor Analysis in Chemistry.
-Leslie
-----Original Message-----
Hello,
does anyone know the meaning of the IND column in the PCA controll field of sixpack (version 0.63)?
I did not found a hint in the sixpack documentation.
Best regards Joerg
** Leslie L. Baker, Ph.D. Department of Plant, Soil and Entomological Sciences University of Idaho Moscow, ID 83844-2339 208-885-9239 http://scholar.google.com/citations?user=ejpH5p0AAAAJ
_______________________________________________ Ifeffit mailing list Ifeffit@millenia.cars.aps.anl.gov http://millenia.cars.aps.anl.gov/mailman/listinfo/ifeffit
Amazon has lots of used copies. I like original sources -- especially since you can look at them and see, for example, that a particular function is described under the heading, "Empirical Methods" instead of relying on what someone told you on the Internet. Sam's Sixpack paper cites Malinowski's 1977 paper, and both are available online. S M Webb (2005) SIXpack: a graphical user interface for XAS analysis using IFEFFIT. Phys. Scr. T115, 1011. E R Malinowski (1977) Determination of the Number of Factors and the Experimental Error in a Data Matrix. Anal Chem 49, 612. -Leslie -----Original Message----- From: ifeffit-bounces@millenia.cars.aps.anl.gov [mailto:ifeffit-bounces@millenia.cars.aps.anl.gov] On Behalf Of Matthew Marcus Sent: Thursday, June 21, 2012 9:29 AM To: XAFS Analysis using Ifeffit Subject: Re: [Ifeffit] Sixpack, PCA controll, "IND" column That book is out of print and hard to get. You should refer to later papers. The IND function is not necessarily robust. It's not rigorously derived, but is sort of empirical. mam On 6/21/2012 9:20 AM, Baker, Leslie wrote:
This is the factor indicator function. Its minimum can be used to indicate the correct number of meaningful factors.
There's an explanation here: http://www.vub.ac.be/fabi/multi/pcr/chaps/chap6.html
For more information, see Malinowski's book Factor Analysis in Chemistry.
-Leslie
-----Original Message-----
Hello,
does anyone know the meaning of the IND column in the PCA controll field of sixpack (version 0.63)?
I did not found a hint in the sixpack documentation.
Best regards Joerg
** Leslie L. Baker, Ph.D. Department of Plant, Soil and Entomological Sciences University of Idaho Moscow, ID 83844-2339 208-885-9239 http://scholar.google.com/citations?user=ejpH5p0AAAAJ
_______________________________________________ Ifeffit mailing list Ifeffit@millenia.cars.aps.anl.gov http://millenia.cars.aps.anl.gov/mailman/listinfo/ifeffit
_______________________________________________ Ifeffit mailing list Ifeffit@millenia.cars.aps.anl.gov http://millenia.cars.aps.anl.gov/mailman/listinfo/ifeffit
participants (3)
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Baker, Leslie -
Joerg Goettlicher -
Matthew Marcus