Gini Impurity
Gini impurity is a measurement used in decision tree algorithms to determine the quality of a split in a dataset. It calculates the probability of a randomly chosen element being incorrectly labeled if it were labeled according to the distribution of labels in the subset.
In the context of feature selection for crypto-asset pricing, lower Gini impurity indicates that a split has effectively separated the data into pure classes or distinct price outcomes. By minimizing this impurity, decision trees and Random Forests can create highly accurate predictive models.
It serves as a primary metric for determining which features are most important for decision-making. Understanding Gini impurity allows for better interpretation of tree-based models used in financial analysis.