Range

What is a range?

Range is the easiest but primitive measure of dispersion. It is not at all a reliable measure of dispersion since it based on 2 extreme observations which are subject to chance and fluctuations.

Range - Definition:

Range is defined as the difference between 2 extreme values of a distribution i.e.,

Range = Maximum value - Minimum value

In descriptive statistics, it is the length of the smallest interval which contains all the required values. It is measured in the same units as the data is provided. It is a poor and weak measure of dispersion except when the sample size is big since it depends on only 2 of the observations.

For a population, the range is higher than or equal to two times the standard deviation, with equality specially for the tossing of coin.

The range in layman's term is the difference between the highest and the lowest values and also referred as the crude range. When a new measurement scale is formed, then a potential minimum/maximum will give forth from this scale. This is referred to as the potential range or crude range. This should not be taken too small, inorder to avoid a ceiling effect. When the range is obtained, the maximum or minimum range resulting would give the crude range.

Mid range Point:

The point halfway between the 2 extremes, an indicator of the central tendency of the data is referred to as the midrange point. Again this is not particularly rich for small samples.

Summary:

Thus, the range of a set of observations is the difference between the highest and the lowest values. To calculate the range, first the data had to rearranged from least to greatest. Then, the smallest value should be subtracted from the biggest value.