Types of variables
What an observation and what a variable is, which four scales of measurement there are and what you may compute with each, and how R records the scale of a column with numbers, text and factors, shown on the game with three doors and the milk survey.
What you will learn
This deck shows you which types of variables there are and what follows for your calculations, and afterwards you can:
- tell observations, variables and values apart in a table and distinguish a variable from a constant
- distinguish the nominal, ordinal, interval and ratio scales and say which statements each allows
- explain why the mean of a category coded as a number means nothing
- choose a fitting R data type for each scale and mark a column as nominal or ordinal with
factor() - name the summaries and plots that the scale of a variable allows
Details
- Level
- Beginner
- Modules
- Empirical Research
- Code
8228- Updated
- 2 November 2026
- Status
- published