Unformatted text preview: e is the signs. To get rid of the
sign trouble, we could use the absolute values:
Mean Absolute Deviation= ∑|x
MAD = i −µ| N = 2.4 + 3.6 + 6.1 + 0.4 + 7.7 20.2
5 = 4.04 Thus, on the average, each datum is 4.04 units from
Note: The idea of MAD is simple. But, in mathematics,
absolute values are not easy to handle. So, MAD is
not popularly used.
not C: Standard Deviation
To get rid of the “sign effect”, and to avoid using
absolute values, we find “squaring” a useful tool.
(i) All values become positive
(ii) A number originally small in magnitude remains small
and a number o...
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- Spring '09
- Standard Deviation, Mean, Deviation, Errors and residuals in statistics