Average Deviation

Absolute Deviation

The absolute deviation is the absolute difference between each value of the statistical variable and the arithmetic mean.

Di = |x - x|

Average Deviation

The average deviation is the arithmetic mean of the absolute deviations.

The average deviation is represented by signo

Average Deviation Formula

Average Deviation

Example

Calculate the average deviation of the following distribution:

9, 3, 8, 8, 9, 8, 9, 18

Average Deviation Operations

Average Deviation Calculations


Average Deviation for Grouped Data

If the data is grouped in a frequency table, the expression of the average deviation is:

Average Deviation for Grouped Data Formula

Average Deviation for Grouped Data

Example

Calculate the average deviation of the following distribution:

  xi fi xi · fi |x - x| |x - x| · fi
[10, 15) 12.5 3 37.5 9.286 27.858
[15, 20) 17.5 5 87.5 4.286 21.43
[20, 25) 22.5 7 157.5 0.714 4.998
[25, 30) 27.5 4 110 5.714 22.856
[30, 35) 32.5 2 65 10.714 21.428
    21 457.5   98.57

Average Deviation Example

Average Deviation Calculation