On 2009.04.18 15:58:30, Jason Morgan wrote: > On 2009.04.18 13:52:35, Serguei Kaniovski wrote: > > I can generate the above dummies but can this design be imputed in a > > reg. model directly?
Oops, I apologize for not reading the whole question. Can you do the following: lm(y ~ I(ifelse(df$i=="AUT"|df$j=="AUT", 1, 0)) + I(ifelse(df$i=="BEL"|df$j=="BEL", 1, 0)) + I(ifelse(df$i=="GER"|df$j=="GER", 1, 0)), data=df) If you exclude the ifelse(), you will get a vector of TRUE/FALSE, which may or may not work. ~Jason > Hello Serguei, > > I am sure there is a better way to do this, but the following seems to > work: > > # Create sample data.frame() > i <- c("AUT", "AUT", "BEL") > j <- c("BEL", "GER", "GER") > df <- data.frame(i=i, j=j) > > # Create dummy vectors > df$d.aut <- ifelse(df$i=="AUT"|df$j=="AUT", 1, 0) > df$d.bel <- ifelse(df$i=="BEL"|df$j=="BEL", 1, 0) > df$d.ger <- ifelse(df$i=="GER"|df$j=="GER", 1, 0) > > # Print results > df > > HTH, > > ~Jason > > -- Jason W. Morgan Graduate Student, Political Science *The Ohio State University* ______________________________________________ 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.