/**
* @test
*/
public function getVariance()
{
$values = $this->getValuesFromData($this->listFilteredByOneSubgroup(true));
$this->assertEquals(10000, $this->statistic->sampleVariance($values));
$values->rewind();
$this->assertEquals(6666.67, $this->statistic->populationVariance($values));
}
function testVariance(Statistic $statistic){
$values = new ArrayObject(array(3,5,2,1,3,4,6,9,3));
assertEquals($statistic->populationVariance($values->getIterator()), 5.11);
assertEquals($statistic->sampleVariance($values->getIterator()), 5.75);
}