Weighted geometric mean: Difference between revisions

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imported>Stephen Repetski
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:''W'' = { ''w''<sub>1</sub>, ''w''<sub>2</sub>, ..., ''w''<sub>''n''</sub>}  
:''W'' = { ''w''<sub>1</sub>, ''w''<sub>2</sub>, ..., ''w''<sub>''n''</sub>}  


the '''weighted geometric mean''' is calculated as
the '''weighted geometric mean''' is  


:<math> \bar{x} = \left(\prod_{i=1}^n x_i^{w_i}\right)^{1 / \sum_{i=1}^n w_i} = \quad \exp \left( \frac{1}{\sum_{i=1}^n w_i} \; \sum_{i=1}^n w_i \ln x_i \right) </math>
:<math> \bar{x} = \left(\prod_{i=1}^n x_i^{w_i}\right)^{1 / \sum_{i=1}^n w_i} = \quad \exp \left( \frac{1}{\sum_{i=1}^n w_i} \; \sum_{i=1}^n w_i \ln x_i \right) </math>


Note that if all the weights are equal, the weighted geometric mean is the same as the [[geometric mean]].
If all the weights are equal, the weighted geometric mean is equal to the[[geometric mean]].


Weighted versions of other means can also be calculated. Probably the best known weighted mean is the weighted arithmetic mean, usually simply called the [[weighted mean]]. Another example of a weighted mean is the [[weighted harmonic mean]].
Weighted versions of other means can also be calculated. Probably the best known weighted mean is the weighted arithmetic mean, usually simply called the [[weighted mean]]. Another example of a weighted mean is the [[weighted harmonic mean]].


==See also==
*[[average]]
*[[central tendency]]
*[[summary statistics]]


[[Category:Means]]
[[Category:Mathematical analysis]]
[[Category:Mathematics Workgroup]]
[[Category:Mathematics Workgroup]]
[[eo:Vikipedio:Projekto matematiko/Laŭpeza geometria meznombro]]
[[ru:Среднее геометрическое взвешенное]]

Revision as of 13:02, 23 January 2007

In statistics, given a set of data,

X = { x1, x2, ..., xn}

and corresponding weights,

W = { w1, w2, ..., wn}

the weighted geometric mean is

If all the weights are equal, the weighted geometric mean is equal to thegeometric mean.

Weighted versions of other means can also be calculated. Probably the best known weighted mean is the weighted arithmetic mean, usually simply called the weighted mean. Another example of a weighted mean is the weighted harmonic mean.