Hi, could it be the "newdata" argument? When I run predict with the newdata argument, I get an error message - a different one though. The second reason might be that your dataset is named df, which is defined as a function an may produce problems. Try renaming the dataset.
yhat=predict(reg1,newdata=x2) x1=seq(1:100) r.norm1=rnorm(100,0,20) x1=r.norm1+x1 x2=x1*2 r.norm2=rnorm(200,0,20) x2=r.norm2+x2 reg1=glm(y1~x1,binomial) yhat=predict(reg1) ##prediction works fine yhat=predict(reg1,newdata=x2) ##gives error message because of "newdata" >Error in eval(predvars, data, env) : numeric 'envir' arg not of length one yhat=predict(reg1,data=x2) ##works fine ##using offset ofst=rep(0.5,100) reg1=glm(y1~x1,binomial,offset=ofst) yhat=predict(reg1) yhat1=predict(reg1,newdata=x2) ##gives error message yhat2=predict(reg1,data=x2) ##works fine ------------------------- cuncta stricte discussurus ------------------------- -----Ursprüngliche Nachricht----- Von: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] Im Auftrag von Tom Guston Gesendet: Friday, April 04, 2008 1:29 PM An: r-help@r-project.org Betreff: [R] predict.glm & newdata Hi all - I'm stumped by the following mdl <- glm(resp ~ . , data = df, family=binomial, offset = ofst) WORKS yhat <- predict(mdl) WORKS yhat <- predict(mdl,newdata = df) FAILS Error in drop(X[, piv, drop = FALSE] %*% beta[piv]) : subscript out of bounds I've tried without offset, quoting binomial. The offset variable ofst IS in df. Previous postings indicate possible names(df) problems (renaming factor levels?) but I'm using the same data.frame for the newdata option. Thank you in advance for any pointers. Tom. _________________________________________________________________ Going green? See the top 12 foods to eat organic. 1N1653A [[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.