I've been doing predictive modelling with R package
caret. When resampling regression models, I get the traditional RMSE and Rsquared metrics, but also RMSE SD and Rsquared SD, for which I haven't found explanation in the manuals or documentations. Please, could anyone enlighten me?
library(mlbench) data(BostonHousing) library(caret) ctrl <- trainControl(method = "cv", number = 2) lmFit <- train(medv ~ ., data = BostonHousing, method = "lm", trControl = ctrl) print(lmFit)
Linear Regression 506 samples 13 predictors No pre-processing Resampling: Cross-Validated (2 fold) Summary of sample sizes: 254, 252 Resampling results RMSE Rsquared RMSE SD Rsquared SD 4.91 0.721 0.202 0.00304