Wiki Page, Math 13 - Perez Sandbox : Module 27 - Chi-Square Test of Independence (Introduction)

Wiki Page
2026-01-17T21:15:48-08:00

This is the beginning of Unit 11. Unit 11 contains only one module, Module 27. This is the last unit in this course.

In this module we learn a new hypothesis test for examining a relationship between two categorical variables. This module does not focus on estimating a parameter, so there is nothing about confidence intervals in this module.

Here is the Big Picture of Statistics with the new material for the Chi-Square Test highlighted in purple.

As you can see in the diagram, we will be using a new probability model, called the Chi-Square curve. But other than that, the logic and process of the hypothesis test are the same.

Note that the diagram describes three distinct hypothesis tests using the Chi-Square curve. We only cover one of these tests, the Test of Independence, which tests a claim about the relationship between two categorical variables in a population. Here are some research questions that can be answered using a Chi-square Test of Independence.

For young adults in the United States, is gender related to body image?

Is alcohol abuse by New York firefighters dependent on participation in the 9/11 rescue operation?

In the United States, is race associated with political views (conservative, moderate, liberal)?