GOODNESS FUNCTIONS

• What are goodness functions?

  
  

  • They are used to measure how good a split is when building a subtree

    
    

  • They aim to maximize the accuracy of the resultant tree or minimize the cost

    
    

• A goodness value is calculated for every possible split using different attribute grouping

  
  

• The best split is chosen according to the goodness values

  
  

• Typical goodness functions

  
  

  • Maximum entropy

    
    

  • Bayesian splitting

    
    

  • Information gain

    
    

  • Gain ratio