While using gbm for a classification problem I came upon the interaction.depth option in the tunGrid function for gbm using caret
gbmGrid <- expand.grid(interaction.depth = c(1, 5, 9), n.trees = (1:30)*50, shrinkage = 0.1, n.minobsinnode = 20)
I am not being able to understand what this option does and why is it used?
Can someone please help me with this??