The main points of difference between dispersion and skewness are given as under:
(1) Dispersion is concerned with measuring the amount of variation in a series rather than with its direction. Skewness is concerned with direction of variation or the departure from symmetry.
(2) Dispersion tells us about the composition of the series whereas skewness tells us about the shape of the series.
(3) Measures of dispersion are based on averages of the first order such as K, M, Z etc. whereas measures of skewness arc based on averages of first and second order such as X , M,Z,cr etc.