by "grouped data" are you saying that you have counts of outcomes and counts of trials? That is how I interpret the glogit in stata. If that is the case you can put your data into glm() like this fit<-glm(nevents~xvars, weights=ntrials, family=binomial, data=yourdataset) will fit the binomial regression model summary(fit) will print the coefficients and model fit In the future could you please read the posting guide and put in a data example or some R code you have tried. CS ----- Corey Sparks, PhD Assistant Professor Department of Demography and Organization Studies University of Texas at San Antonio 501 West Durango Blvd Monterey Building 2.270C San Antonio, TX 78207 210-458-3166 corey.sparks 'at' utsa.edu https://rowdyspace.utsa.edu/users/ozd504/www/index.htm -- View this message in context: http://r.789695.n4.nabble.com/grouped-logit-regression-tp2280763p2280806.html Sent from the R help mailing list archive at Nabble.com.