ExtraTrees.md (548B)
1 # Extra Trees (Extremely randomized trees) 2 3 ML D5 4 5 **Definition:** Extra trees are decisions trees that incorporate extra randomness by randomizing splitting thresholds instead of using gini impurity of information gain to determine splitting thresholds. 6 7 Basically, each leaf selects a random feature and then selects a random value that is in the set of valid inputs for the node and splits upon that. This adds lots of randomness and greatly reduces training time because the optimal split at each point in time does not need to be calculated.