Dispersion and Skewness

The following are the principal points of difference between dispersion and skewness:

• Dispersion deals with the dispersal of the items of a series around its central value but skewness deals with the nature of distribution of a series i.e. to find out whether the series is symmetrically distributed, or not.
• Dispersion speaks of the amount of variation of the items from their average value but skewness speaks of the direction of the variation of the items, i.e. whether it is towards the right, or left of the distribution.
• Dispersion is computed both on the basis, and form of certain averages, but skewness is computed only on the basis of he averages viz. Mean, Median, Mode, Quartiles and Percentiles.
• Dispersion studies the degree of variation in the data, but skewness studies the concentration of the data either in lower or higher values.
• Dispersion speaks of the representative character of a central value, and skewness speaks of the normalcy, or otherwise of the distribution.

Dispersion indicates the general shape of a frequency distribution but skewness indicates how the dispersion on the two sides of the Mode varies in the arrangement of frequencies.