Dispersion Measures

Mary claims that the range, standard deviationand varianceare all measures of dispersion. John adds to Mary’s claim by stating that the coefficient of variationis a measure of relative dispersion. Do you agree with both Mary and John? Why?

Without knowing something about how data is dispersed, measures of central tendency may be misleading. For example, a residential street with 20 homes on it having a mean value of $200,000 with little variation from the mean would be very different from a street with the same mean home value but with 3 homes having a value of $1 million and the other 17 clustered around $60,000. Measures of dispersion provide a more complete picture. Dispersion measures include the range, coefficient of variation, variance, and standard …

Standard deviation and variance are discussed.