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<?php |
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declare(strict_types=1); |
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namespace Phpml\Metric; |
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use Phpml\Exception\InvalidArgumentException; |
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use Phpml\Math\Statistic\Correlation; |
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use Phpml\Math\Statistic\Mean; |
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final class Regression |
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{ |
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View Code Duplication |
public static function meanSquaredError(array $targets, array $predictions): float |
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{ |
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self::assertCountEquals($targets, $predictions); |
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$errors = []; |
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foreach ($targets as $index => $target) { |
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$errors[] = (($target - $predictions[$index]) ** 2); |
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} |
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return Mean::arithmetic($errors); |
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} |
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public static function meanSquaredLogarithmicError(array $targets, array $predictions): float |
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{ |
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self::assertCountEquals($targets, $predictions); |
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$errors = []; |
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foreach ($targets as $index => $target) { |
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$errors[] = (log(1 + $target) - log(1 + $predictions[$index])) ** 2; |
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} |
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return Mean::arithmetic($errors); |
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} |
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View Code Duplication |
public static function meanAbsoluteError(array $targets, array $predictions): float |
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{ |
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self::assertCountEquals($targets, $predictions); |
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$errors = []; |
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foreach ($targets as $index => $target) { |
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$errors[] = abs($target - $predictions[$index]); |
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} |
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return Mean::arithmetic($errors); |
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} |
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View Code Duplication |
public static function medianAbsoluteError(array $targets, array $predictions): float |
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{ |
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self::assertCountEquals($targets, $predictions); |
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$errors = []; |
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foreach ($targets as $index => $target) { |
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$errors[] = abs($target - $predictions[$index]); |
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} |
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return (float) Mean::median($errors); |
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} |
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public static function r2Score(array $targets, array $predictions): float |
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{ |
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self::assertCountEquals($targets, $predictions); |
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return Correlation::pearson($targets, $predictions) ** 2; |
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} |
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View Code Duplication |
public static function maxError(array $targets, array $predictions): float |
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{ |
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self::assertCountEquals($targets, $predictions); |
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$errors = []; |
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foreach ($targets as $index => $target) { |
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$errors[] = abs($target - $predictions[$index]); |
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} |
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return (float) max($errors); |
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} |
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private static function assertCountEquals(array &$targets, array &$predictions): void |
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{ |
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if (count($targets) !== count($predictions)) { |
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throw new InvalidArgumentException('Targets count must be equal with predictions count'); |
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} |
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} |
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} |
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Duplicated code is one of the most pungent code smells. If you need to duplicate the same code in three or more different places, we strongly encourage you to look into extracting the code into a single class or operation.
You can also find more detailed suggestions in the “Code” section of your repository.