Discuss the importance of measures of Dispersion?

Dispersion measures the extent to which different items tend to disperse or deviate away from the central tendency. While, central tendency refers to a central value or a representative value of a statistical series, on the other hand, dispersion measures the deviation of the various items of the statistical series from the central value.

Thus, it can be said that the study of dispersion supplements the study of central tendency and helps in the understanding of overall composition of the statistical series. The measures of dispersion such as range, quartile deviation, mean deviation and Standard Deviation measure the quantum of variation. For example, if a country has very high income group people and very low income group people, then we can say that the country has large income disparity.