Comparison of categorical and quantitative variables

A variable can be classified as one of the following types:

Categorical variables: Categorical variables are also called qualitative variables or attribute variables. The values of a categorical variable are mutually exclusive categories or groups. Categorical data may or may not have some logical order.
Quantitative variables: The values of a quantitative variable are numbers that usually represent a count or a measurement.

Often, you will collect both categorical data and quantitative data when exploring a single subject. Categorical variables are often used to group or subset the data in graphs or analyses. Here are some examples of categorical and quantitative data that you could collect when exploring the same subject:

Subject of the analysis	Possible categorical variables	Possible quantitative variables
Household appliance sales	Type of appliance; Make and model	Sale price
Automobile body painting	Paint flaws (peel, scratch, smudge, other); Paint colors	Temperature of metal to be painted; Thickness of paint layer

The following tables show examples of categorical and quantitative variables for different types of data:

Examples of categorical variables

Data type	Examples
Numeric	Gender (1=Female, 2=Male) Survey results (1=Agree, 2=Neutral, 3=Disagree)
Text	Payment method (Cash or Credit) Machine settings (Low, Medium, High) Product types (Wood, Plastic, Metal)
Date/time	Days of the week (Monday, Tuesday, Wednesday) Months of the year (January, February, March)

Examples of quantitative variables

Data type	Examples
Numeric	Number of customer complaints Proportion of customers eligible for a rebate Fill weight of a cereal box
Date/time	Date and time payment is received Date and time of technical support incident