Which of the following is considered the highest scale in measurement?

The ratio scale is the highest level of measurement because it possesses all properties of the lower scales plus a true zero.

Its absolute zero means ratios like twice or half are meaningful, as with weight, age or income.

Nominal is the lowest scale, using numbers only as labels for distinct categories.

Ordinal ranks cases in order but the gaps between ranks are unequal and undefined.

Interval has equal, meaningful gaps yet only an arbitrary zero, as with temperature in Celsius.

Moving up the four scales adds mathematical power, so ratio permits the widest range of statistics.