Jeff Harring wrote: > > I am looking for R code to be able to fit a linear-linear piecewise > model with person-specific changepoint. I have searched the web, but > have not been able to locate any code. > > .. > I would appreciate any advice on this code or guidance as to where to > search for example code to fit this nonlinear mixed effects model. > >
I had good success in fitting piecewise functions with continuous derivatives, e.g. a logistic function with a linear continuation. Things did not work well with nlme when there was a discontinuity. There is an discussion from 2000 right from Douglas Bates' and Mary Lindstrom's mouth for nls and the hockey-stick, so it could be possible to get is to work with good data. http://www.biostat.wustl.edu/archives/html/s-news/2000-04/msg00209.html Also check http://markmail.org/message/6p63i4cxfk6enlp5 Dieter -- View this message in context: http://n4.nabble.com/question-about-nlme-tp1474561p1474765.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.
