Nominal / Ordinal / Interval / Ratio scales

Nominal: A ranking/order of the variables is not possible and ther is no standardized difference between th variables. Eg. colours (blue, red etc.)

Ordinal: A ranking/order of the variables is possible, but there is no standardized difference between th variables. Eg. schoolgrades from 1-5. Like the difference between 1 and 2 isnt exactly the same as the difference between 3 and 4.

Interval: A ranking/order of the variables is possible, furthermore there is an equal difference between the variables. However there is no absolute “true ” zero point, so you can’t set these varuables in a ratio. Eg. the Celsius temperature scale.

Ratio: A ranking/order of the variables is possible, furthermore there is an equal difference between th variables. Also there is an absolute “true ” zero point, so you can set these varuables in a ratio. Eg. the Celsius temperature scale.