Have you looked at nlme and the book Pinheiro and Bates (2000) Mixed-Effects Models in S and S-Plus (Springer)? I'm not familiar with "NSUR", but it sound like nlme might handle it very well.
hope this helps, Spencer Graves Thomas Wutzler wrote: > Dear r-Help readers, > > 1) Is there support for NSUR in some R package yet? > 2) Is there a general function of applying the Gauss-Newton or Marquard > method, in which the function of calculating the partial derivatives can > be specified by the user? > > Contemporaneously correlated non-linear models (NSUR) is a method to fit > a system of non-linear equations. > > I want to use to fit several non-linear models at the same time, so that > one the independent variable is alsway the sum of several other > independent variable of other models. > This procedure is described in detail by Parresol 2001. He used PROC > MODEL by SAS to accomplish the task. > > If there is no support for NSUR yet, I would try to program a function > by myself, although I only used very simple R-functins yet. The > essential part is the fit the minimum of complex vector equation. This > leads to my second question above. The function (as provided as an > parameter) should accept a vector of model parameters and calculate the > matrix of partial derivatives at this point in the parameter space. > > > Thanks > Thomas > > Parresol, B.R., 2001. Additivity of nonlinear biomass equations. > Canadian Journal of Forest Research-Revue Canadienne De Recherche > Forestiere 31, 865-878. > > ______________________________________________ > R-help@stat.math.ethz.ch mailing list > https://stat.ethz.ch/mailman/listinfo/r-help > PLEASE do read the posting guide! http://www.R-project.org/posting-guide.html ______________________________________________ R-help@stat.math.ethz.ch mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide! http://www.R-project.org/posting-guide.html