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Trader> <stats_stat_powersum
[edit] Last updated: Fri, 17 May 2013

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stats_variance

(PECL stats >= 1.0.0)

stats_varianceReturns the population variance

Beschreibung

float stats_variance ( array $a [, bool $sample = false ] )
Warnung

Diese Funktion ist bis jetzt nicht dokumentiert. Es steht nur die Liste der Argumente zur Verfügung.

Parameter-Liste

a

sample

Rückgabewerte



add a note add a note User Contributed Notes stats_variance - [1 notes]
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Anonymous
4 years ago
This will return surprising values for most users, since the default of sample=false is rather unusual when speaking about variance.

Point is:
When using stats_variance($foo,TRUE) the sum is divided by n-1 while the default just divides it by n. So when you expect your variance to be lower you probable wanted to divide by n-1, therefore should set the second parameter =TRUE.

 
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