Categorical Variable

Categorical Variable

A categorical variable is a variable that places observations into groups or categories. Instead of measuring “how much,” categorical variables describe “which kind.”

Examples of Categorical Variables

Variable

Example Categories

Eye color

blue, brown, green

Favorite pet

dog, cat, fish

Political party

independent, democrat, republican

Grade level

9th, 10th, 11th, 12th

Each observation belongs to one category.

Categorical vs. Quantitative Variables

Type of Variable

What It Describes

Categorical Variable

Which group or category

Quantitative Variable

How much or how many

For example:

  • Favorite ice cream flavor → categorical

  • Number of scoops eaten → quantitative

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