I have a binomial model with one covariate, x1, treated as a factor with 3 levels. The other covariate is measured x2 <- 1:30. The response, y, is the proportion of successes out of 20 trials.
glm(cbind(y, 20 - y) ~ x1 * x2, family = binomial)
Now, I would like to constrain the cofficients on 2 levels of the factor, x1, to be identical and test the difference between these models by a likelihood ratio test.
How can I get glm() to constrain the coefficients on 2 levels to be the same?
Thanks, ANDREW
______________________________________________ [EMAIL PROTECTED] mailing list https://www.stat.math.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide! http://www.R-project.org/posting-guide.html
