Hi, It is slightly clunky but:
mod2 <- glm(Y ~ offset(I(1.3 * X1)) + X2, family = "binomial") should do the trick. See ?offset for details. Cheers, Josh On Thu, Jul 21, 2011 at 7:42 PM, Johan Jackson <johan.h.jack...@gmail.com> wrote: > Hello all, > > I am using a glm() and would like to fix one of the regression coefficients > to be a particular value and see what happens to the fit of the model. E.g.: > > mod1 <- glm(Y ~ X1 + X2,family='binomial') > mod2 <- glm(Y~[fixed to 1.3]X1 + X2,family='binomial') > > The beta for X1 is freely estimated in mod1 but is constrained to be 1.3 in > mod2. Is there a way to do this? > > Thank you in advance, > > JJ > > [[alternative HTML version deleted]] > > ______________________________________________ > 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. > -- Joshua Wiley Ph.D. Student, Health Psychology University of California, Los Angeles https://joshuawiley.com/ ______________________________________________ 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.
