ABSTRACT
The goal of analytic methods is to use data to better understand the factors that influence the results of sporting events. Probability theory is the branch of mathematics that deals with random outcomes. This chapter considers the basic properties and rules of probability, focusing on those concepts that are useful in analyzing sports data. The starting point for probability theory is the concept of an experiment. An experiment is simply any process that generates a random outcome. There are several reasons why odds may be more convenient to use than probabilities. One is that, for very large or very small probabilities, odds are often easier to understand. The basic rules of probability are concerned with events, which can describe any possible specific outcome that might occur when an experiment is performed. However, in applying analytic methods to sports, we are generally concerned with data; that is, we analyze numbers, not events.
