On Aug 20, 2011, at 12:57 PM, peter dalgaard wrote:


On Aug 20, 2011, at 18:04 , Stephen Davies wrote:

As for "$stdres," that would be wonderful, but
as you can see from the above list of attributes, it's not one of the 8
returned. What am I missing?

An upgrade, most likely.

Whoosh. Sometimes I am simply clueless. I didn't notice that 'stdres' was missing from the names in Stephen's output. Laura Thompson has a very nice R/S accompaniment to Agresti's "Categorical Data Analysis" text and she shows how to adjust the Pearson residuals to make them "standardized". What follows is directly from pages 37-38 of her work:

#--------------------------------------------------#
resid.pear <- residuals(fit.glm, type = "pearson")

Note that the sum of the squared Pearson residuals equals the Pearson chi-squared statistic:

sum(resid.pear^2)
[1] 69.11429

To get the standardized residuals, just modify resid.pear according to the formula on p. 81 of Agresti.

ni<-rowSums(table.3.2.array) # row sums

nj<-colSums(table.3.2.array) # column sums
n<-sum(table.3.2.array)  # total sample size
resid.pear.mat<-matrix(resid.pear, nc=3, byrow=T, dimnames=list(c("<HS","HS or JH",
"Bachelor or Grad"),c("Fund", "Mod", "Lib")))

n*resid.pear.mat/sqrt(outer(n-ni,n-nj,"*") ) # standardized Pearson residuals

                      Fund        Mod       Lib
             <HS  4.534062 -2.5520482 -1.941537
        HS or JH  2.552988  1.2859745 -3.994669
Bachelor or Grad -6.806638  0.7007539  6.250329

#--------------------------------------------------#

You can also look at the code (once you upgrade) and the method in R is quite similar, although the R codes calcualtes the stdres values separately rather than adjusting the Pearson residuals


--
Peter Dalgaard, Professor,
Center for Statistics, Copenhagen Business School


David Winsemius, MD
West Hartford, CT

______________________________________________
R-help@r-project.org mailing list
https://stat.ethz.ch/mailman/listinfo/r-help
PLEASE do read the posting guide http://www.R-project.org/posting-guide.html
and provide commented, minimal, self-contained, reproducible code.

Reply via email to