Chapter 5. Divide and Conquer – Classification Using Decision Trees and Rules
To make a difficult decision, some people weigh their options by making lists of pros and cons for each possibility. Suppose a job seeker was deciding between several offers, some closer or further from home, with various levels of pay and benefits. He or she might create a list with the features of each position. Based on these features, rules can be created to eliminate some options. For instance, "if I have a commute longer than an hour, then I will be unhappy", or "if I make less than $50k, I won't be able to support my family." The difficult decision of predicting future happiness can be reduced to a series of small, but increasingly specific choices.
This chapter covers decision trees and rule learners—two machine learning methods that apply a similar strategy of dividing data into smaller and smaller portions to identify patterns that can be used for prediction. The knowledge is then presented in the form...