Hi Sigalit, yes, you can see this from the fact that the table says unit"1" meaning that it compares 1 to 0 and not vice versa. Everytime you regress on dummies the label will have added this to the original variable name. Say you have gender "male" and "female". Then "gendermale" in the label of your summary table would indicate that "female" is coded 0 and male 1 and that you therefore compare how much more or less of the dependent variable males "have" over females (and not vice versa). In case of a binomial regression it would of course be how much more or less likely they are on average (with the appropriate transformation) ...
Does that help you? Cheers, Daniel ------------------------- cuncta stricte discussurus ------------------------- -----Ursprüngliche Nachricht----- Von: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] Im Auftrag von sigalit mangut-leiba Gesendet: Saturday, February 23, 2008 3:05 PM An: r-help Betreff: [R] clarification about glm Hello, I have a question about glm: if i have a binary covariate (unit=1,0) the reference group would be 0? (prediction for unit=1) example: dat1<-data.frame(y,unit,x1,x2) log_u <- glm(y~.,family=binomial,data=dat1) summary(log_u) Estimate Std. Error z value Pr(>|z|) (Intercept) -0.54247 0.24658 -2.200 0.0278 * unit1 -0.13052 0.22861 -0.571 0.5680 aps 0.03098 0.01433 2.162 0.0306 * tiss0 0.02522 0.01101 2.291 0.0219 * Thank you, Sigalit. [[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. ______________________________________________ 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.
