Decision Trees

Overview

A decision tree is a set of rules that partition a data set into multiple spaces. It can usually be thought as being a series of questions that you can answer for each data point, which classifies the point.

For example, in determining the risk for a certain disease, you may ask the following questions:

• Is the patient male or female?
• Is the patient older than 50?
• Does the patient have diabetes?

Each question partitions the data space into two sections. By asking a series of questions, you partition the space even further.

Types

• Classification Tree - used to partition data into a finite set of categories
  Binary - each node has either 0 or 2 children.
• Regression Tree