Dear list, Apologies, I have sent this message before but received no replies so I'm trying again just in case...
Motivated by the discovery of 'loglet analysis' (http://phe.rockefeller.edu/LogletLab/) that allows decomposition of growth curves into a series of logistic equations, I attempted to do the same thing in R. #SIMULATED DATA Time <- 1:200 pop.size <- SSlogis(Time,10,20,5) + SSlogis(Time,20,100,20) + rnorm(length(Time)) ts.plot(pop.size) #MY ANALYSIS results <- nls(pop.size ~ SSlogis(Time, Asym1, xmid1, scal1) + SSlogis(Time, Asym2, xmid2, scal2), start = list(Asym1=5, xmid1=15, scal1=30, Asym2=25, xmid2=60, scal2=25)) THE RESULT I get the error message: Error in nls(size ~ SSlogis(Time, Asym1, xmid1, scal1) + SSlogis(Time, : step factor 0.000488281 reduced below `minFactor' of 0.000976563 Any hints in making this analysis work would be greatly appreciated. Dan Bebber ____________________________ Dr. Daniel P. Bebber Department of Plant Sciences University of Oxford South Parks Road Oxford OX1 3RB Tel. 01865 275060 Web. http://www.forestecology.co.uk/ ______________________________________________ [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
