Dear all, I have a data set (QTL detection) where I have two cols of factors in the data frame that correspond logically (in my model) to the same factor. In fact these are haplotype classes. Another real-life example would be family gas consumption as a function of car company (e.g. Ford, GM, and Honda) (assuming 2 cars by family).
An artificial example follows: set.seed(1234) L3 <- LETTERS[1:3] (d <- data.frame( y=rnorm(10), fac=sample(L3, 10, repl=TRUE),fac1=sample(L3,10,repl=T))) lm(y ~ fac+fac1,data=d) and I get: Coefficients: (Intercept) facB facC fac1B fac1C 0.3612 -0.9359 -0.2004 -2.1376 -0.5438 However, to respect my model, I need to constrain effects in fac and fac1 to be the same, i.e. facB=fac1B and facC=fac1C. There are logically just 4 unknowns (average,A,B,C). With continuous covariates one might do y ~ I(cov1+cov2), but this is not the case. Is there any trick to do that? Thanks, Andres Legarra INRA-SAGA Toulouse, France ______________________________________________ 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.