Chapter 4. Classification: placing things where they belong

 

This chapter covers

  • Understanding classification techniques
  • Detecting fraud with logistic regression
  • Classification in very large datasets

“What is this?” is the question children perhaps ask most frequently. The popularity of that question among children—whose inquisitive nature is as wonderful as it is persistent—shouldn’t be surprising. In order to understand the world around us, we organize our perceptions into groups and categories. In the previous chapter, we presented a number of algorithms that can help us determine structure from our data. In this chapter, we’ll look at classification algorithms that help us assign each data point to an appropriate category or class (hence the term classification). The act of classification would answer a child’s question by providing a statement in the form “This is a boat,” “This is a tree,” “This is a house,” and so on.

4.1. The need for classification

4.2. An overview of classifiers

4.3. Fraud detection with logistic regression

4.4. Are your results credible?

4.5. Classification with very large datasets

4.6. Summary