7th Grade · Statistics & Probability
Mean Absolute Deviation (MAD)
7.SP.B.3
Definition
The average distance of all data values from the mean. Steps: find the mean, find |each value − mean|, then find the average of those distances.
Examples
- For {2,4,6,8,10}: mean = 6, MAD = (4+2+0+2+4)÷5 = 2.4.
- A MAD of 2.4 means data values are, on average, 2.4 units from the mean.
Key rule
Larger MAD means more spread out; smaller MAD means more clustered.
Memory hook
On average, how far is each point from the center?