Dear list, i'm checking the residuals plots of a gam model after a processus of model selection. I found the "best" model, all my terms are significant, the r-square and the deviance explained are good, but I have strange residuals plots:
http://dl.dropbox.com/u/1169100/gam.check.png http://dl.dropbox.com/u/1169100/residuals_vs_fitted.png The curve is caused by the zeroes in my data. I've also plotted each explanatory variables included in the model against residuals and everything looks fine. Is this curve does not allow me to accept this model? Does the use of an other family (eg negbin) would be the solution for fixing this problem? Currently I use the poisson family (and quasipoisson). I have a lot of 0 in my response variable, almost 65 %.... Should I use a specific function that allows me to use zero-inflated data?? Kind regards, Sam [[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.
