Calculating child entropies
You have completed the first step for measuring the information gain that color provides — you computed the disorder of the root node. Now you need to measure the entropy of the child nodes so that you can assess if the collective disorder of the child nodes is less than the disorder of the parent node. If it is, then you have gained some information about loan default status from the information found in color.
Cet exercice fait partie du cours
Dimensionality Reduction in R
Instructions
- Calculate the class probabilities for the left split (blue side).
- Calculate the entropy of left split using the class probabilities.
- Calculate the class probabilities for the left split (green side).
- Calculate the entropy of right split using the class probabilities.
Exercice interactif pratique
Essayez cet exercice en complétant cet exemple de code.
# Calculate the class probabilities in the left split
p_left_yes <- ___
p_left_no <- ___
# Calculate the entropy of the left split
entropy_left <- -(___ * ___(___)) +
-(___ * ___(___))
# Calculate the class probabilities in the right split
p_right_yes <- ___
p_right_no <- ___
# Calculate the entropy of the right split
entropy_right <- -(___ * ___(___)) +
-(___ * ___(___))