# set tunning parameters
> control <- trainControl(method = "cv", number = 5)

# random forest model

> rf.model <- train(Sales ~ ., data = my.data, method = "parRF", trControl = control, prox = TRUE, allowParallel = TRUE)

The session took forever to run, even I used method = "parRF", the parallel implementation of random forest, it still didn't work.

When I switched to use randomForest instead, it had the same issues, the session took forever, and never finished.

# random forest model
> forest.model <- randomForest(Sales ~ ., data = my.data, mtry = 15, ntree = 1000)