MathPHP\Statistics\EffectSizeTest::testCohensD PHP Method

    public function testCohensD($μ₁, $μ₂, $s₁, $s₂, $expected)
    {
        $d = EffectSize::cohensD($μ₁, $μ₂, $s₁, $s₂);
        $this->assertEquals($expected, $d, '', 1.0E-5);
    }