Class: HybridForest::Trees::GiniImpurity

Inherits:
Object
  • Object
show all
Includes:
Impurity
Defined in:
lib/hybridforest/trees/impurity_metrics/gini_impurity.rb

Instance Method Summary collapse

Methods included from Impurity

#information_gain, #weighted_impurity

Instance Method Details

#compute(instances) ⇒ Object 



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# File 'lib/hybridforest/trees/impurity_metrics/gini_impurity.rb', line 10

def compute(instances)
  total_count = instances.count.to_f
  label_counts = instances.count_labels.each_value
  1 - label_counts.sum { |count| (count / total_count)**2 }
end