Statistics: Chi-Squared Tests

Objectives

• Students will recognize that chi-squared tests are for counts of categorical data.
• Students will identify the appropriate chi-squared test to use for a given situation: Goodness of Fit Test, Test of Independence, or Test of Homogeneity.
• Students will learn how to calculate the degrees of freedom for each type of chi-squared test.
• Students will interpret the results of a chi-square test.
• Students will reason abstractly and quantitatively.

Vocabulary

•  goodness-of-fit
• categorical data
• observed counts
•  p-value
• degrees of freedom
•  test of homogeneity
• expected counts
•  test of independence

About the Lesson

This lesson involves investigating chi-squared tests and distributions. Students will compare different scenarios and determine which chi-square test is appropriate. They will look at chi-square test results and make the correct decision to reject or fail to reject the null hypothesis and write their conclusions in context.