You could use the BRugs package and formulate your prior knowledge about slopes in terms of a probability distribution.
Michele Christina Itten kirjoitti: > Is there a way to force certain formula parameters to be nonnegative? > > What I want to do is to estimate student capacity over time, namely by > >> capacity ~ Student + Student:Day > > I add this formula to a glm call and obtain negative learning slope estimates > (Student:Day) in some cases. > However, I don't want to allow for that. In such a case, glm should solve > >> capacity ~ Student > > and I will set the slope to zero. > > Is there an option to constrain a parameter set to nonnegative values? > > > > > Many thanks in advance! > > Michele Itten, > BS. Carnegie Mellon > > ______________________________________________ > 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. > > -- ------------------------------------------ Samu Mäntyniemi Researcher Fisheries and Environmental Management Group (FEM) Department of Biological and Environmental Sciences Biocenter 3, room 4414 Viikinkaari 1 P.O. Box 65 FIN-00014 University of Helsinki Phone: +358 9 191 58710 Fax: +358 9 191 58257 email: [EMAIL PROTECTED] personal webpage: http://www.helsinki.fi/people/samu.mantyniemi/ FEM webpage: http://www.helsinki.fi/science/fem/ ______________________________________________ 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.
