[R] Autocorrelation in R for NLS
Hello Can someone please let me know how to test for Autocorrelation in R ( eg. like durbin-watson statistic or any other test) after performing Non linear least squares and what can be the best solution for it. Thanks Regards Ruchita [[alternative HTML version deleted]] __ 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.
Re: [R] NLS-Weibull-ERROR
Hello I was trying to estimate the weibull model using nls after putting OLS values as the initial inputs to NLS. I tried multiple times but still i m getting the same error of Error in nlsModel(formula, mf, start, wts) : singular gradient matrix at initial parameter estimates. The Program is as below vel - c(1,2,3,4,5,6,7,8,9,10,11,12,13,14) df - data.frame(conc, vel) df conc vel 10.077 1 20.328 2 30.882 3 41.195 4 51.884 5 63.577 6 76.549 7 8 13.000 8 9 33.690 9 10 52.220 10 11 90.140 11 12 166.050 12 13 233.620 13 14 346.890 14 plot(df$vel, df$conc) para0.st - c(K=450, + alpha=0.054,beta=3.398 ) fit0 - nls( + conc~ K-(K*exp(-(vel/alpha)^beta)), df, start= para0.st,trace=T) Error in nlsModel(formula, mf, start, wts) : singular gradient matrix at initial parameter estimates I will be highly thankful if some one can please let me know where is the mistake as i m unable to trace it. Thanks Ruchita On Wed, Dec 16, 2009 at 3:18 PM, ruchita gupta ruchitarg...@gmail.comwrote: Hello After performing NLS estimates for some sigmoid model(like logistic growth model and Gompertz growth models), how can we get the RMSE(root mean square error) and MAPE(mean absolute percentage error) in R statistical tool for comparison between two models Thanks Ruchita [[alternative HTML version deleted]] __ 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.
[R] MAPE and RMSE in R
Hello After performing NLS estimates for some sigmoid model(like logistic growth model and Gompertz growth models), how can we get the RMSE(root mean square error) and MAPE(mean absolute percentage error) in R statistical tool for comparison between two models Thanks Ruchita [[alternative HTML version deleted]] __ 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.
[R] R square in NLS-urgent help
Hello I need one urgent help I am trying to fit the Sigmod curve of logistic growth model using NLS estimation. But i do not get the R square value in that even after getting the Summary In that case how to compare the fit for 3 models and find which one is better fit?? How to get this R Square value when using NLS estimation? Thanks Ruchita [[alternative HTML version deleted]] __ 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.
[R] R square in NLS-urgent help
Hello I need one urgent help I am trying to fit the Sigmod curve of logistic growth model using NLS estimation. But i do not get the R square value in that even after getting the Summary In that case how to compare the fit for 3 models and find which one is better fit?? How to get this R Square value when using NLS estimation? Thanks Ruchita [[alternative HTML version deleted]] __ 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.
[R] R square in NLS-urgent help
Hello I need one urgent help I am trying to fit the Sigmod curve of logistic growth model using NLS estimation. But i do not get the R square value in that even after getting the Summary In that case how to compare the fit for 3 models and find which one is better fit?? How to get this R Square value when using NLS estimation? Thanks Ruchita [[alternative HTML version deleted]] __ 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.
