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

[David STADELMANN]

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?

Thanks a lot for your help.
David

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