## Quick Reference

In statistics, the arithmetic mean of the deviations (all taken as positive numbers) of all the numbers in a set of numbers from their arithmetic mean. For example, the arithmetic mean of 5, 8, 9, and 10 is 8, and therefore the deviations from this mean are 3, 0, 1, and 2, giving a mean deviation of 1.5. Compare standard deviation.

*Subjects:*
Science and Mathematics — Financial Institutions and Services.