/**
* @dataProvider dataProviderForPMF
*/
public function testPMF(int $x, int $r, float $P, float $pmf)
{
$this->assertEquals($pmf, NegativeBinomial::PMF($x, $r, $P), '', 0.001);
}
/**
* Pascal distribution (convenience method for negative binomial distribution)
* Probability mass function
* https://en.wikipedia.org/wiki/Negative_binomial_distribution
*
* b(x; r, P) = ₓ₋₁Cᵣ₋₁ pʳ * (1 - P)ˣ⁻ʳ
*
* @param int $x number of trials required to produce r successes
* @param int $r number of successful events
* @param float $P probability of success on an individual trial
*
* @return float
*/
public static function PMF(int $x, int $r, float $P) : float
{
return NegativeBinomial::PMF($x, $r, $P);
}