Hello, I am looking to generate propensity score in R using ps() command. My question comes from how to include categorical variables in the equation to generate propensity score. How should I include reference category in the estimation? Should I drop the reference group manually before running the estimation or R would automatically omit it as if I include it in the estimation? I look forward to your response!
Qian Zhang Department of Sociology University of South Carolina [[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.