[R] GLM Logit and coefficient testing (linear combination)

[Henric Nilsson]

On Sö, 2005-12-18, 17:32, David STADELMANN skrev:
> Hi,
>
> I am running glm logit regressions with R and I would like to test a
> linear combination of coefficients (H0: beta1=beta2 against H1:
> beta1<>beta2). Is there a package for such a test or how can I perform
> it otherwise (perhaps with logLik() ???)?
>
> Additionally I was wondering if there was no routine to calculate pseudo
> R2s for logit regressions. Currently I am calculating the pseudo R2 by
> comparing the maximum value of the log-Likelihood-function of the fitted
> model with the maximum log-likelihood-function of a model containing
> only a constant. Any better ideas?

The subject of R^2 in logistic regression was brought up some time ago.
See the postings

http://finzi.psych.upenn.edu/R/Rhelp02a/archive/54939.html
http://finzi.psych.upenn.edu/R/Rhelp02a/archive/54940.html

You could easily have found these, and couple of other ones, all by
yourself just by issuing an `RSiteSearch("R^2 logistic")'.


HTH
Henric