On Oct 30, 2009, at 7:47 PM, CE.KA wrote:
Sorry there was a mistake:
I could not see what was different?
Hi R users I want to do a multiple linear regression with R With a normal model (Y=Cste+A1*X1+A2*X2) the program would be lm(Y~X1+X2) My model is Y=Cste+A1*X1+A2*X2 with the constraint A1=-A2 What is the program for such a model?
Try calculating X3= X2-X1 and estimate the shared parameter with: lm(y ~ X3) or instead; lm(Y ~ I(X2 - X1) ) -- David Winsemius, MD Heritage Laboratories West Hartford, CT ______________________________________________ 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.
