The four levels of measurement are Nominal, Ordinal, Interval, and Ratio.

Nominal - Mutually exclusive, categories, Exhaustive

Ordinal- Mutually exclusive, categories, Exhaustive and Rank ordered

Interval- Mutually exclusive, categories, Exhaustive with Rank ordered plus you can measure the distance between / numerical value. This measurement does not have a 0 point so there are no percentages or ratios.

Ratio- Mutually exclusive, categories, Exhaustive with Rank ordered. This measurement does have a 0 point indicating the absence of the variable.

Nominal - Mutually exclusive, categories, Exhaustive

Ordinal- Mutually exclusive, categories, Exhaustive and Rank ordered

Interval- Mutually exclusive, categories, Exhaustive with Rank ordered plus you can measure the distance between / numerical value. This measurement does not have a 0 point so there are no percentages or ratios.

Ratio- Mutually exclusive, categories, Exhaustive with Rank ordered. This measurement does have a 0 point indicating the absence of the variable.