12: Chi‐square Tests for Categorical Data
- Page ID
- 20860
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Often we want to conduct tests claims about the characteristics of qualitative or categorical non‐ numeric data. In Chapter 10, we covered a test of one population proportion. In reality, this was a test of a categorical variable with 2 choices (success, failure). Now in this section, we will expand our study of hypothesis tests involving categorical data to include categorical random variables with more than two choices using a goodness‐of‐fit test. In addition, we will compare two categorical variables for independence. Both of these models will use a Chi‐square test statistic, which looks at deviations between the observed values and expected values of the data.