Hi Mirela, >> Are the relative R^2 values the CP values?
No. CP is your complexity parameter. >> I’ve read that the R^2 = 1-rel error, so I am assuming that in my case >> this >> would be 1-0.64949. Is this correct? Yes. See ?rsq.rpart, and run the example, which I've copied below. ## par(ask=T) z.auto <- rpart(Mileage ~ Weight, car.test.frame) rsq.rpart(z.auto) par(ask=F) The values plotted in graph-1 come from 1-rel.error and 1-xerror. HTH, Mark. Mirela Tulbure wrote: > > Dear R-list members, > > I am doing a CART analysis in R using the rpart function in the rpart > package: > Phrag.rpart=rpart(PhragDiff~., data = Phrag, method="anova", xval=10). > > I used the xerror values in the CP table to prune the tree to 4 nsplits: > > CP nsplit rel error xerror xstd > 1 0.098172 0 1.00000 1.02867 0.12768 > 2 0.055991 3 0.70548 1.00823 0.12911 > 3 0.029306 4 0.64949 0.83275 0.12074 > 4 0.018943 5 0.62019 0.86994 0.12467 > 5 0.010503 6 0.60124 0.86975 0.12080 > 6 0.010000 7 0.59074 0.87944 0.11757 > > I would like to get R^2 values for the model as well as partial R^2 values > for each split. > I’ve read that the R^2 = 1-rel error, so I am assuming that in my case > this would be 1-0.64949. Is this correct? Are the relative R^2 values the > CP values? > > Your help would be much appreciated. Many thanks in advance, > > Mirela > > > > ____________________________________________________________________________________ > Looking for la > ols.search.yahoo.com/newsearch/category.php?category=shopping > > ______________________________________________ > [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 > and provide commented, minimal, self-contained, reproducible code. > > -- View this message in context: http://www.nabble.com/model-R%5E2-and-partial-R%5E2-values-tp15772594p15773072.html Sent from the R help mailing list archive at Nabble.com. ______________________________________________ [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 and provide commented, minimal, self-contained, reproducible code.
