Individual Series
When calculating the mean deviation for an individual series, the deviations from the mean or median are added together. The sum is then divided by the number of items in the series.
Steps to Calculate Mean Deviation
- Determine the specific average (Mean or Median) from which the mean deviation will be calculated.
- Determine the absolute (positive) deviations of all observations from the specific average.
- Then the absolute deviations are added together to find out Σ|D|
- Apply the formula:
Example:
Calculate mean deviation from mean and median for the given data: 10, 18, 21, 32, 44
Solution:
Mean Deviation from the Mean
Mean = 25
Mean Deviation from Mean = 10.4
Mean Deviation from the Median
= Size of 3rd item
Median = 21
Mean Deviation from Median = 9.6