8. Discrete Probability Distributions

A numerical variable whose value depends on the outcome of a chance or random event is called a random variable. If the set of possible values of a random variable is countable or finite, it is called a discrete random variable.

A discrete probability distribution function has two characteristics:

• Each probability is between zero and one, inclusive.
• The sum of the probabilities is one.

Adapted from Python for Introductory Statistics, by Simon Aman (Truman College, City Colleges of Chicago), licensed under CC BY 4.0. Changes were made: reformatted as an accessible XYZ web edition with live in-browser code cells. License: CC-BY-4.0.