And zero seconds means no time has elapsed. Today, i will teach you the four levels of measurement nominal, ordinal, interval scale. An example is time, the difference between 1 second and 2 seconds is the same as the difference between 123 and 124 seconds. Zero means there is none of the quality you are measuring. Ratio: here the difference between two values has meaning, and the value of zero also has special meaning.However, interval variables are different from ratio variables because zero is just another number on the scale, with no special significance – it is arbitrarily chosen. For instance, the difference between 29F and 30F is the same as the difference between 43F and 44F. A variable can be treated as nominal when its values represent categories with no intrinsic ranking (for example, the department of the company in. Nominal and ordinal data can be either string (alphanumeric) or numeric.