Lopez, Dan
2013-Nov-26 20:08 UTC
[R] How do I extract Random Forest Terms and Probabilities?
Hi R Experts, I need your help with two question regarding randomForest. 1. When I run a Random Forest model how do I extract the formula I used so that I can store it in a character vector in a dataframe? For example the dataframe might look like this if I am running models using the IRIS dataset #ModelID,Type, #001,RF,Species ~ Sepal.Length + Sepal.Width + Petal.Length + Petal.Width fmi<-randomForest(Species~.,iris,mtry=3,ntry=500) #I know one place where the information is in fmi$terms but not sure how to extract just the formula info. Or perhaps there is somewhere else in fmi that I could get this? 2. How do I get the probabilities (probability-like values) from the model that was run? I know for the test set I can use predict. And I know to extract the classifications from the model I use fmi$predicted. But where are the probabilities? Dan Workforce Analyst HRIM - Workforce Analytics & Metrics LLNL [[alternative HTML version deleted]]
Hi, For the first part, you could do: fmi2 <- fmi attributes(fmi2$terms) <- NULL capture.output(fmi2$terms) #[1] "Species ~ Sepal.Length + Sepal.Width + Petal.Length + Petal.Width" A.k. On Tuesday, November 26, 2013 3:55 PM, "Lopez, Dan" <lopez235 at llnl.gov> wrote: Hi R Experts, I need your help with two question regarding randomForest. 1.? ? ? When I run a Random Forest model how do I extract the formula I used so that I can store it in a character vector in a dataframe? For example the dataframe might look like this if I am running models using the IRIS dataset #ModelID,Type, #001,RF,Species ~ Sepal.Length + Sepal.Width + Petal.Length + Petal.Width fmi<-randomForest(Species~.,iris,mtry=3,ntry=500) #I know one place where the information is in fmi$terms but not sure how to extract just the formula info. Or perhaps there is somewhere else in fmi that I could get this? 2.? ? ? How do I get the probabilities (probability-like values) from the model that was run? I know for the test set I can use predict. And I know to extract the classifications from the model I use fmi$predicted. But where are the probabilities? Dan Workforce Analyst HRIM - Workforce Analytics & Metrics LLNL ??? [[alternative HTML version deleted]] ______________________________________________ R-help at 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.