Dear list members, I want to fit a linear model to a data set that contains several independent variables, some of them continuous and some of them binary. For the binary variables I am using 1-of-N encoding but I also have two variables that correspond to mixture ratios. How can I declare to the model that their sum equals unity? Or perhaps should I treat them as factors instead of random variables constrained to [0,1]? Thank you very much in advance. Best Regards Kyriakos Kachrimanis. -.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.- r-help mailing list -- Read http://www.ci.tuwien.ac.at/~hornik/R/R-FAQ.html Send "info", "help", or "[un]subscribe" (in the "body", not the subject !) To: r-help-request at stat.math.ethz.ch _._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._