title: Decision Tree Learning and Impurity
body: <p>There are three ways to measure impurity:</p>
  
  <p><img src="https://i.stack.imgur.com/TEodj.png" alt="Entropy"></p>
  
  <p><img src="https://i.stack.imgur.com/F4A7p.png" alt="Gini Index"></p>
  
  <p><img src="https://i.stack.imgur.com/wMkvp.png" alt="Classification Error"></p>
  
  <p>What are the differences and appropriate use cases for each method?</p>