To find the absolute deviation (more specifically, the mean absolute deviation), follow these steps:
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Calculate the Mean: Determine the average of your dataset. This is done by summing all the values in the dataset and dividing by the number of values.
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Calculate the Absolute Deviations: For each number in the dataset, subtract the mean you calculated in step 1. Then, take the absolute value of the result. The absolute value of a number is its distance from zero, meaning you ignore the sign (positive or negative).
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Sum the Absolute Deviations: Add up all the absolute deviations you calculated in step 2.
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Calculate the Mean Absolute Deviation (MAD): Divide the sum of the absolute deviations (from step 3) by the total number of values in your original dataset. This final result is the mean absolute deviation.
In Summary:
The mean absolute deviation is calculated as follows:
MAD = (Sum of |value - mean|) / (Total number of values)
Example:
Let's say our dataset is: 2, 4, 6, 8, 10
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Mean: (2 + 4 + 6 + 8 + 10) / 5 = 30 / 5 = 6
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Absolute Deviations:
- |2 - 6| = 4
- |4 - 6| = 2
- |6 - 6| = 0
- |8 - 6| = 2
- |10 - 6| = 4
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Sum of Absolute Deviations: 4 + 2 + 0 + 2 + 4 = 12
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Mean Absolute Deviation (MAD): 12 / 5 = 2.4
Therefore, the mean absolute deviation of the dataset 2, 4, 6, 8, 10 is 2.4.
Why is Mean Absolute Deviation Useful?
The mean absolute deviation provides a measure of the average distance each data point is from the mean of the dataset. It gives you a sense of the data's variability. A smaller MAD indicates data points are clustered closer to the mean, while a larger MAD indicates they are more spread out.