Dear R-listers, I would like to know if there is a way to programmatically generate parameter start values for the model y~(a*exp(b*x)+c*exp(d*x)) in R. I've scoured the help files and archives for nls() and similar searches, and have read Fox 2002 - the best advice has been to make estimates from a priori knowledge of the data. However, in the Matlab CurveFit tool, reliable start values are somehow estimated 'heuristically', as is claimed in their help files. Is there a similar R routine than may produce reasonable start values?
Many thanks, Paul Brewin Paul E Brewin (PhD) Center for Research in Biological Systems University of California San Diego 9500 Gilman Drive MC 0505 La Jolla CA, 92093-0505 USA Ph: 858-822-0871 Fax: 858-822-3610 ______________________________________________ [email protected] 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.
