Mean Absolute Deviation Calculator
Calculate the mean absolute deviation (MAD) to measure average distance of data points from the mean.
Mean Absolute Deviation
3.0000
Mean Absolute Deviation vs Value 1
Formule
## How to Calculate Mean Absolute Deviation ### Formula **MAD = (1/n) * Sum of |xi - mean|** For each value, find the absolute difference from the mean, then average those differences. Unlike variance, MAD does not square the deviations, making it less sensitive to outliers and easier to interpret: it is literally the average distance from the mean.
Exemple Résolu
Find the MAD of 3, 6, 9, 12.
- 01Mean = (3 + 6 + 9 + 12) / 4 = 30 / 4 = 7.5
- 02Absolute deviations: |3-7.5|=4.5, |6-7.5|=1.5, |9-7.5|=1.5, |12-7.5|=4.5
- 03Sum of absolute deviations = 4.5 + 1.5 + 1.5 + 4.5 = 12
- 04MAD = 12 / 4 = 3
Questions Fréquentes
How does MAD differ from standard deviation?
MAD uses absolute deviations while SD uses squared deviations. MAD is more robust to outliers and easier to interpret, but SD has nicer mathematical properties for theoretical statistics.
Is MAD always smaller than standard deviation?
For most distributions, yes. For a normal distribution, MAD ≈ 0.7979 * SD. Squaring in SD amplifies large deviations, making SD generally larger.
When should I use MAD?
Use MAD when you want a robust, easily interpretable measure of spread, especially if outliers are present or the distribution is non-normal.
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