Range – General Information

The range of a set of data is the difference between the highest and lowest values in the set. For example : 21, 55, 12, 84, 32, 64. Range = 84 – 12 = 72.

The range, in the sense of the difference between the highest and lowest scores, is also called the crude range. When a new scale for measurement is developed, then a potential maximum or minimum will emanate from this scale. This is called the potential (crude) range. Of course this range should not be chosen too small, in order to avoid a ceiling effect. When the measurement is obtained, the resulting smallest or greatest observation, will provide the observed (crude) range.