Gini Impurity
MediumMachine LearningMathArray
Description
Given an array labels of class labels, return the Gini impurity 1 - sum(p_i²) where p_i is the proportion of each class, rounded to 4 decimal places.
Examples
Input:
labels = [0,0,1,1]Output:
0.5Explanation:
Subtracting the summed squared class proportions from one gives an impurity of 0.5.
Input:
labels = [1,1,1]Output:
0Explanation:
Subtracting the summed squared class proportions from one gives an impurity of 0.
Input:
labels = [0,1,2,0]Output:
0.625Explanation:
Subtracting the summed squared class proportions from one gives an impurity of 0.625.
Constraints
- •
1 ≤ labels.length ≤ 10⁴