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PHPUnit version bump and removed ELO

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This commit is contained in:
Alex Wulf
2022-07-05 15:42:21 +02:00
parent 97609a3eac
commit afce4e56ca
14 changed files with 1285 additions and 718 deletions
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14
src/Elo/EloRating.php
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@ -1,14 +0,0 @@
<?php namespace DNW\Skills\Elo;
use DNW\Skills\Rating;
/**
* An Elo rating represented by a single number (mean).
*/
class EloRating extends Rating
{
public function __construct($rating)
{
parent::__construct($rating, 0);
}
}

37
src/Elo/FideEloCalculator.php
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@ -1,37 +0,0 @@
<?php namespace DNW\Skills\Elo;
use DNW\Skills\GameInfo;
/**
* Including Elo's scheme as a simple comparison.
* See http://en.wikipedia.org/wiki/Elo_rating_system#Theory
* for more details
*/
class FideEloCalculator extends TwoPlayerEloCalculator
{
public function __construct(FideKFactor $kFactor)
{
parent::__construct($kFactor);
}
public static function createWithDefaultKFactor()
{
return new FideEloCalculator(new FideKFactor());
}
public static function createWithProvisionalKFactor()
{
return new FideEloCalculator(new ProvisionalFideKFactor());
}
public function getPlayerWinProbability(GameInfo $gameInfo, $playerRating, $opponentRating)
{
$ratingDifference = $opponentRating - $playerRating;
return 1.0
/
(
1.0 + pow(10.0, $ratingDifference / (2 * $gameInfo->getBeta()))
);
}
}

14
src/Elo/FideKFactor.php
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@ -1,14 +0,0 @@
<?php namespace DNW\Skills\Elo;
// see http://ratings.fide.com/calculator_rtd.phtml for details
class FideKFactor extends KFactor
{
public function getValueForRating($rating)
{
if ($rating < 2400) {
return 15;
}
return 10;
}
}

27
src/Elo/GaussianEloCalculator.php
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@ -1,27 +0,0 @@
<?php namespace DNW\Skills\Elo;
use DNW\Skills\GameInfo;
use DNW\Skills\Numerics\GaussianDistribution;
class GaussianEloCalculator extends TwoPlayerEloCalculator
{
// From the paper
const STABLE_KFACTOR = 24;
public function __construct()
{
parent::__construct(new KFactor(self::STABLE_KFACTOR));
}
public function getPlayerWinProbability(GameInfo $gameInfo, $playerRating, $opponentRating)
{
$ratingDifference = $playerRating - $opponentRating;
// See equation 1.1 in the TrueSkill paper
return GaussianDistribution::cumulativeTo(
$ratingDifference
/
(sqrt(2) * $gameInfo->getBeta())
);
}
}

18
src/Elo/KFactor.php
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@ -1,18 +0,0 @@
<?php namespace DNW\Skills\Elo;
class KFactor
{
const DEFAULT_KFACTOR = 24;
private $_value;
public function __construct($exactKFactor = self::DEFAULT_KFACTOR)
{
$this->_value = $exactKFactor;
}
public function getValueForRating($rating)
{
return $this->_value;
}
}

12
src/Elo/ProvisionalFideKFactor.php
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@ -1,12 +0,0 @@
<?php namespace DNW\Skills\Elo;
/**
* Indicates someone who has played less than 30 games.
*/
class ProvisionalFideKFactor extends FideKFactor
{
public function getValueForRating($rating)
{
return 25;
}
}

93
src/Elo/TwoPlayerEloCalculator.php
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@ -1,93 +0,0 @@
<?php namespace DNW\Skills\Elo;
use Exception;
use DNW\Skills\GameInfo;
use DNW\Skills\PairwiseComparison;
use DNW\Skills\RankSorter;
use DNW\Skills\SkillCalculator;
use DNW\Skills\SkillCalculatorSupportedOptions;
use DNW\Skills\PlayersRange;
use DNW\Skills\TeamsRange;
abstract class TwoPlayerEloCalculator extends SkillCalculator
{
protected $_kFactor;
protected function __construct(KFactor $kFactor)
{
parent::__construct(SkillCalculatorSupportedOptions::NONE, TeamsRange::exactly(2), PlayersRange::exactly(1));
$this->_kFactor = $kFactor;
}
public function calculateNewRatings(GameInfo $gameInfo, array $teamsOfPlayerToRatings, array $teamRanks)
{
$this->validateTeamCountAndPlayersCountPerTeam($teamsOfPlayerToRatings);
RankSorter::sort($teamsOfPlayerToRatings, $teamRanks);
$result = array();
$isDraw = ($teamRanks[0] === $teamRanks[1]);
$team1 = $teamsOfPlayerToRatings[0];
$team2 = $teamsOfPlayerToRatings[1];
$player1 = each($team1);
$player2 = each($team2);
$player1Rating = $player1["value"]->getMean();
$player2Rating = $player2["value"]->getMean();
$result[$player1["key"]] = $this->calculateNewRating($gameInfo, $player1Rating, $player2Rating, $isDraw ? PairwiseComparison::DRAW : PairwiseComparison::WIN);
$result[$player2["key"]] = $this->calculateNewRating($gameInfo, $player2Rating, $player1Rating, $isDraw ? PairwiseComparison::DRAW : PairwiseComparison::LOSE);
return $result;
}
protected function calculateNewRating($gameInfo, $selfRating, $opponentRating, $selfToOpponentComparison)
{
$expectedProbability = $this->getPlayerWinProbability($gameInfo, $selfRating, $opponentRating);
$actualProbability = $this->getScoreFromComparison($selfToOpponentComparison);
$k = $this->_kFactor->getValueForRating($selfRating);
$ratingChange = $k * ($actualProbability - $expectedProbability);
$newRating = $selfRating + $ratingChange;
return new EloRating($newRating);
}
private static function getScoreFromComparison($comparison)
{
switch ($comparison)
{
case PairwiseComparison::WIN:
return 1;
case PairwiseComparison::DRAW:
return 0.5;
case PairwiseComparison::LOSE:
return 0;
default:
throw new Exception("Unexpected comparison");
}
}
public abstract function getPlayerWinProbability(GameInfo $gameInfo, $playerRating, $opponentRating);
public function calculateMatchQuality(GameInfo $gameInfo, array $teamsOfPlayerToRatings)
{
$this->validateTeamCountAndPlayersCountPerTeam($teamsOfPlayerToRatings);
$team1 = $teamsOfPlayerToRatings[0];
$team2 = $teamsOfPlayerToRatings[1];
$player1 = $team1[0];
$player2 = $team2[0];
$player1Rating = $player1[1]->getMean();
$player2Rating = $player2[1]->getMean();
$ratingDifference = $player1Rating - $player2Rating;
// The TrueSkill paper mentions that they used s1 - s2 (rating difference) to
// determine match quality. I convert that to a percentage as a delta from 50%
// using the cumulative density function of the specific curve being used
$deltaFrom50Percent = abs($this->getPlayerWinProbability($gameInfo, $player1Rating, $player2Rating) - 0.5);
return (0.5 - $deltaFrom50Percent) / 0.5;
}
}

6
src/Player.php
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@ -57,10 +57,6 @@ class Player implements ISupportPartialPlay, ISupportPartialUpdate
public function __toString()
{
if ($this->_Id != null) {
return (string)$this->_Id;
}
return parent::__toString();
return (string)$this->_Id;
}
}