What is information gain ?

We can define information gain as a measure of how much information a feature provides about a class. Information gain helps to determine the order of attributes in the nodes of a decision tree.

The main node is referred to as the parent node, whereas sub-nodes are known as child nodes. We can use information gain to determine how good the splitting of nodes in a decision tree.

It can help us determine the quality of splitting, as we shall soon see. The calculation of information gain should help us understand this concept better.