Question

Why isn’t arithmetic appropriate for an ordinal scale?

Answer 1

Answer:-

As ordinal scale classifies things according to Rank.

Ordinal means order as first, second, third etc.

Then applying any arithmetic on ranks don't give us a significant meaningful result.

For example, on a survey you might code Educational Attainment as 0=less than high school; 1=some high school.; 2=high school degree; 3=some college; 4=college degree; 5=post college. In this measure, higher numbers mean more education. But is distance from 0 to 1 same as 3 to 4.The interval between values is not interpretable in an ordinal measure.

Also , here mean value also have to no significant meaning.

Thus, arithmetic is not appropriate for an ordinal scale.