Page 4 - H.A Measures of dispersion (xi)

Mean deviation is the arithmetic average of deviation of all the values taken from a statistical
average of series. In taking deviation of values, algebraic signs + and – are not taken into
consideration, that is negative deviations are also treated as positive deviations”.
(i) Formulas for Mean Deviation
(a) If deviations are taken from median, the following formula is used

(b) If deviation are taken from arithmetic mean of the series

(ii) Coefficient of Mean Deviation

• Coefficient of mean deviation from Mean =
• Coefficient of MD from Median =
• Coefficient of MD from Mode =

(iii) Calculation of Mean Deviation or Coefficient of Mean Deviation
(a) Individual Series

Estimating MD through Median, MD =

Estimating MD through Mean, MD =
Estimating Coefficient of MD through Median Coefficient of MD =

Estimating Coefficient of MD through Mean Coefficient of MD =