Definition
Numerical variable
A variable whose possible values are numerical counts or measurements.
What it means
A variable is the feature you record, and its value can change from one person or object to another. A numerical variable changes as a meaningful number: number of pets, height in centimetres, or travel time in minutes. The recorded answers are the numerical data for that variable.
Remember it
The variable is the question; the data are its number answers.
Example
“Travel time to school in minutes” is a numerical variable. The answers 8, 12, 15, and 20 minutes are numerical data collected for that variable.
Watch for
“Bus route number” is usually not a numerical variable because the numbers identify routes rather than measure how much or how many.
Common mix-up
A numerical variable is the changing feature being measured; numerical data are the values recorded for it.
Exact meaning
A numerical variable is a variable whose observed values are numbers representing counts or measurements, so differences and other numerical comparisons between values are meaningful.