[R] Ellipse in PCA with parameters "a" and "b"defined.

David L Carlson dcarlson at tamu.edu
Tue Jan 22 15:14:47 CET 2013


Try x <- mean(PCA$scores[,1]) and y <- mean(PCA$scores[,2]) which should be
the same as x <- 0, y <- 0 within rounding error.

----------------------------------------------
David L Carlson
Associate Professor of Anthropology
Texas A&M University
College Station, TX 77843-4352

> -----Original Message-----
> From: r-help-bounces at r-project.org [mailto:r-help-bounces at r-
> project.org] On Behalf Of mary
> Sent: Tuesday, January 22, 2013 3:40 AM
> To: r-help at r-project.org
> Subject: Re: [R] Ellipse in PCA with parameters "a" and "b"defined.
> 
> Ok...
> so, in my model my "a"  is built using the standard deviation of the
> first
> principal component and "b" with the second, so my "x" and "Y" should
> be :
>  PCA $ scores [, 1], PCA $ scores [, 2]
> but in this way I do not get out a confidence interval set on my
> parameters
> but many ellipses.
> 
> Thanks
> Mary
> 
> 
> 
> --
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> PCA-with-parameters-a-and-b-defined-tp4656215p4656242.html
> Sent from the R help mailing list archive at Nabble.com.
> 
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