> attr(terms(~B*A), "term.labels") [1] "B" "A" "B:A" > attr(terms(~A/C), "term.labels") [1] "A" "A:C" > attr(terms(~B*A/C), "term.labels") [1] "B" "A" "B:A" "B:A:C" > attr(terms(~(B*A)/C), "term.labels") [1] "B" "A" "B:A" "B:A:C" > attr(terms(~B*(A/C)), "term.labels") [1] "B" "A" "A:C" "B:A" "B:A:C" >
The issue is precedence of operations. "*" has higher precedence than "/". This is exactly the same issue you see in ordinary arithmetic > 1+2*3 [1] 7 > (1+2)*3 [1] 9 > Rich [[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.