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Last updated: Fri, 20 May 2011

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stats_variance

(PECL stats >= 1.0.0)

stats_varianceDevuelve la varianza de población

Descripción

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

Esta función no está documentada actualmente, solamente se encuentra disponible la lista de parámetros.

Parámetros

a

sample

Valores devueltos



add a note add a note User Contributed Notes stats_variance
Anonymous 27-Feb-2009 09:43
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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