Hi, Robbert Langenberg <mcrelay <at> gmail.com> writes: > I am trying to get a prediction of my GAM on a response type. So that I > eventually get plots with the correct values on my ylab. > The problem I am encountering now is that I cannot seem to get it done for > the following type of model: > > *model3<-gam(y_no~s(day,by=mapID),family=binomial, data=mergeday)* > > My mapID consists of 8 levels of which I get individual plots with * > plot(model3)*. When I do predict with a newdata in it just like my first > model I need all columns to have the same amount of rows or else R will not > except it ofcourse, the col.names need to at least include day and mapID. > This way I can not get a prediction working for this GAM, I am confused > because of this part in the model: *s(day,by=mapID). > > I hope someone can help me out with this, > > Sincerely yours, > > Robbert Langenberg I'm not sure that this will work for you, but I had a similar situation and was able to get predict to work (after helpful advice from Simon Wood) with a by variable by generating a model matrix for a model with the interaction of the covariate and the by term, something like
model.matrix(~ day:mapID - 1, data = mergeday) in your case. I added the appropriate columns into my data frame and also to the newdata for predict. You can see an example in the appendix of http://www.journalofvision.org/8/16/10/ HTH, Ken -- Ken Knoblauch Inserm U846 Institut Cellule Souche et Cerveau Département Neurosciences Intégratives 18 avenue du Doyen Lépine 69500 Bron France tel: +33 (0)4 72 91 34 77 fax: +33 (0)4 72 91 34 61 portable: +33 (0)6 84 10 64 10 http://www.sbri.fr ______________________________________________ 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.
