Thank you David
David Winsemius wrote: > > > 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. > > -- View this message in context: http://old.nabble.com/Multiple-linear-regression-with-constraint-%28imposition%29-tp26138081p26141453.html Sent from the R help mailing list archive at Nabble.com. ______________________________________________ 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.