/**
* The sum of squares of Y equals the sum of squares regression plus the sum of squares of error (residual)
* SStotal = SSreg + SSres
* @dataProvider dataProviderForSumOfSquaresEqualsSumOfSQuaresRegressionPlusSumOfSquaresResidual
*/
public function testSumOfSquaresEqualsSumOfSQuaresRegressionPlusSumOfSquaresResidual(array $points)
{
$regression = new Linear($points);
$SStot = $regression->sumOfSquaresTotal();
$SSreg = $regression->sumOfSquaresRegression();
$SSres = $regression->sumOfSquaresResidual();
$this->assertEquals($SStot, $SSreg + $SSres, '', 0.001);
}
/**
* @dataProvider dataProviderForOutliers
*/
public function testOutliers($points, $cook, $DFFITS)
{
$regression = new Linear($points);
$test_cook = $regression->cooksD();
$test_dffits = $regression->DFFITS();
foreach ($test_cook as $key => $value) {
$this->assertEquals($value, $cook[$key], '', 1.0E-7);
}
foreach ($test_dffits as $key => $value) {
$this->assertEquals($value, $DFFITS[$key], '', 1.0E-7);
}
}
