To determine how much difference there is between two individuals with respect to some characteristic, you must use either an interval or a ratio scale of measurement.

Question

Quizplus · Accepted Answer

Interval and ratio scales of measurement allow for the calculation of meaningful numerical differences between values, which is necessary for determining differences between individuals with respect to a characteristic. Other scales such as nominal or ordinal scales do not provide this level of measurement precision.

To Determine How Much Difference There Is Between Two Individuals