Hello, For gam, try model1$aic. The returned value is an object of class "gam" as described in ?gamObject. For gamm, try model$gam$aic. The returned value is a list of two objects, a "gam" and the return value of "lme" or "|gammPQL".
See ?gam and ?gamm, the Value section. Hope this helps, Rui Barradas | Em 22-08-2012 13:00, ritapatricio escreveu: > Dear all, > > I am analysing growth data - response variable - using GAM and GAMM models, > and 4 covariates: mean size, mean capture year, growth interval, having > tumors vs. not > The models work fine, and fit the data well, however when I try to compare > models using AIC I cannot get an AIC value. > > This is the code for the gam model: > >> model1=gam(growth_rate~s(sampling_year)+s(growth_interval)+s(mean_SCL)+FP_status,family=quasi(link=identity),method="REML") >> AIC(model1) > [1] NA > > or: >> model2=gam(growth_rate~s(sampling_year)+s(mean_SCL),family=quasi(link=identity),method="REML") >> AIC(model1,model2) > df AIC > model1 13.722861 NA > model2 9.898634 NA > > I have tried several models and AIC always comes as 'NA', can someone help? > > many thanks. > > rita patrÃcio > > > > > > > -- > View this message in context: > http://r.789695.n4.nabble.com/AIC-for-GAM-models-tp4640972.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. [[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.
