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Lesson 3: Mean Absolute Deviation6.DS.6c

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I can…

I can find the mean absolute deviation (MAD) to describe how spread out data is.

Mean Absolute Deviation — The average distance of each number from the mean.
Deviation — How far a number is from the mean.
Absolute Value — How far a number is from zero. It is never negative. It is never negative.
Spread — How far apart the numbers are.
Data distribution — How the data looks: where it sits and how spread out it is.
Variability — How spread out the numbers are.

My data set: 6, 8, 10, 12. First I find the mean: 6 + 8 + 10 + 12 = 36, then 36 ÷ 4 = 9. The mean is 9.
Next I find each deviation (value − mean): 6−9 = −3, 8−9 = −1, 10−9 = 1, 12−9 = 3.
Then I take the absolute value of each (the distance, always positive): 3, 1, 1, 3.
Finally I average those distances: 3 + 1 + 1 + 3 = 8, then 8 ÷ 4 = 2. So the MAD = 2 points.

Data set: 4, 8, 6, 10, 2. The mean is 6. What is the MAD?

2.4

Deviations: −2, 2, 0, 4, −4. Absolute deviations: 2, 2, 0, 4, 4. Sum = 12. MAD = 12 ÷ 5 = 2.4.

I know ___ because ___.

Goal: I can explain my work using the words mean absolute deviation, deviation, absolute value, and spread.