Lesson 2: Probability

Overview Section

For every new lesson, it is important to keep in mind the goal of statistics and where we are in achieving that goal. The goal is to make inferences about the population based on the sample. In Lesson 1, we learned how to obtain a sample by collecting data. We also learned how to describe the data in that sample using descriptive statistics and graphs. This lesson starts us on the path to inference.

In order to learn about inference, we need to learn a few more things first. Inference requires an understanding of probability, random variables, and probability distributions (Lesson 3). This Lesson will focus on the first step, probability.


Upon successful completion of this lesson, you should be able to:

  • Translate an event of interest into common probability notation.
  • Translate common probability notation into a phrase or sentence describing the event of interest.
  • Compute and interpret set operations numerically and with diagrams.
  • Determine if two events are independent, mutually exclusive or neither.
  • Compute and interpret conditional events and conditional probabilities.
  • Apply Bayes' Theorem.