factanal question

-----Original Message-----
From: r-help-bounces at r-project.org [mailto:r-help-bounces at r-project.org]

Behalf Of William Revelle
Sent: December-01-08 10:26 AM
To: John Fox; 'Don McNeil'
Cc: r-help at r-project.org
Subject: Re: [R] factanal question

Don and John,
   factor.residuals in the psych package does what you want (and
basically what  John wrote).

Bill


At 9:30 AM -0500 12/1/08, John Fox wrote:

Dear Don,

All long as you leave the factors unrotated or do an orthogonal rotation

is the default), you can compute reproduced correlations among the

from the factor loadings, and thus residual correlations given the

and the original correlation matrix, both of which are accessible in the
object returned by factanal(); the following isn't carefully tested, but
should work:

repRes <- function(F, round=3){
  A <- loadings(F)
  R <- F$correlation
  RR <- A %*% t(A)
  ResR <- R - RR
  list(reproduced.correlations=round(RR, round),
    residual.correlations=round(ResR, round))
  }

Here F is an object returned by factanal(). The diagonal elements of the
reproduced correlations are the communalities, and of the residual
correlations, the uniquenesses.

To do this from an oblique rotation would require the factor-correlation
matrix, which, as has been pointed out previously, factanal() oddly

provide. In this case, that's not a real impediment, since reproduced and
residual correlations are invariant with respect to rotation of the

I hope this helps,
 John

------------------------------
John Fox, Professor
Department of Sociology
McMaster University
Hamilton, Ontario, Canada
web: socserv.mcmaster.ca/jfox

 -----Original Message-----
 From: r-help-bounces at r-project.org

On

 Behalf Of Don McNeil
 Sent: November-30-08 11:39 PM
 To: r-help at r-project.org
 Subject: [R] factanal question

 Dear R users:
 I'm wondering if it's possible to get the residual correlation matrix

when

 using factanal.
 Since factanal assumes that the errors are normally distributed and
 independent (provided the factor model fits the data) this would be

useful.

 Of course you would need to submit the data to the function to get the
 residuals (not just their correlation matrix), but it should be

to

 get the residual correlation matrix if only the data correlation

is

 provided.
 Don McNeil

--
William Revelle		http://personality-project.org/revelle.html
Professor

Department of Psychology

Northwestern University	http://www.northwestern.edu/
Attend  ISSID/ARP:2009               http://issid.org/issid.2009/