How can you explain different scales in statistics?

Answer 1

A scale is the entire amount of values that a variable could in principle have.

For example a variable "age in years" could have any value that is a number equal to or above zero, so it's scale consists of: 0, 1, 2, 3, 4, 5 ...................... and so on, and theoretically it even includes values like 3.5 (= 3 years and 6 months).

So THAT is a scale.

There are DIFFERENT TYPES of scales, which are:

nominal scales: When you can only check whether two values from this scale are EQUAL OR DIFFERENT then it's a nominal scale.

(e.g. a variable "Name of a Person")

ordinal scale: if you can also check which of two values from this scale is "larger" then it's an ordinal scale.

interval scale: if you can also give a precise answer about the difference between two values from this scale, then it's an interval scale.

(e.g. "Year of Birth")

ratio scale: If you can also calculate precisely how much bigger or smaller one value of this scale is than another (as in "twice as big as...." or "0.34 timese as big as") that it's a ratio scale.

(e.g. "weight" or "number of children")