> Here are the codes of the example of lm( ): > > ## Annette Dobson (1990) "An Introduction to > Generalized Linear Models". > ## Page 9: Plant Weight Data. > ctl <- > (4.17,5.58,5.18,6.11,4.50,4.61,5.17,4.53,5.33,5.14) > trt <- > (4.81,4.17,4.41,3.59,5.87,3.83,6.03,4.89,4.32,4.69) > group <- gl(2,10,20, labels=c("Ctl","Trt")) > weight <- c(ctl, trt) > anova(lm.D9 <- lm(weight ~ group)) > lm.D90 <- lm(weight ~ group - 1) # omitting intercept > > What I am doing is let the variable name "group" > stored in a vector, say, g <- "group". The question is > how to strip the quotation marks when we call lm( ) > through g?
Try: w = "weight" g = "group" form = as.formula(paste(w,g,sep="~")) lm(form) Regards, Richie. Mathematical Sciences Unit HSL ------------------------------------------------------------------------ ATTENTION: This message contains privileged and confidential inform...{{dropped:20}} ______________________________________________ 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.