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Multilingual Demographic Dictionary, second unified edition, English volume

Mean deviation

Multilingual Demographic Dictionary, second unified edition, English vol.
Revision as of 08:14, 9 January 2010 by NBBot (talk | contribs) (Etienne van de Walle et al., second 1982 edition)
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Mean deviation  (MEAN deviation)


The dispersion 1, scatter 1, variation 1 or variability 1 of a set of observations depends on the differences 2 or deviations 2 between its elements. Here only the most common measures of dispersion 3 are mentioned. The range 4 is the difference between the largest and the smallest values of a set of elements. The interquartile range 5 is the difference between the first and the third quartiles (142-2) and contains half the observations in the set. The semi-interquartile range 6, also called the quartile deviation 6, which is half the interquartile range, is often taken as a measure of dispersion. The mean deviation 7 or average deviation 7 is the arithmetic mean (140-2) of the positive values of the deviations of the individual items from the average, the variance 8 is the arithmetic mean of the squares of these deviations and the standard deviation 9 is the square root of the variance.

  • 9. The common notation for the standard deviation is σ.

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