Class EloRating

java.lang.Object

org.episteme.social.sports.EloRating

public final class EloRating
extends Object

Implementation of the Elo rating system for measuring relative skill levels in zero-sum games and sports competitions. Reference: Elo, Arpad (1978). The Rating of Chessplayers, Past and Present.

Since:

1.0

Version:

1.1

Author:

Silvere Martin-Michiellot, Gemini AI (Google DeepMind)

Method Summary

Modifier and Type	Method	Description
static double	calculateExpectedScore(double ratingA, double ratingB)	Calculates the expected score (probability of winning) for player A.
static double	updateRating(double currentRating, double actualScore, double expectedScore, double kFactor)	Calculates the newly adjusted rating for a player after a match.

Methods inherited from class Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Method Details

calculateExpectedScore

public static double calculateExpectedScore(double ratingA,
 double ratingB)

Calculates the expected score (probability of winning) for player A.

Parameters:

ratingA - skill rating of player A

ratingB - skill rating of player B

Returns:

expected score between 0.0 and 1.0

updateRating

public static double updateRating(double currentRating,
 double actualScore,
 double expectedScore,
 double kFactor)

Calculates the newly adjusted rating for a player after a match.

Parameters:

currentRating - the previous rating

actualScore - the outcome (1.0 = win, 0.5 = draw, 0.0 = loss)

expectedScore - the pre-match probability calculated via calculateExpectedScore(double, double)

kFactor - the sensitivity factor (e.g., 32 for novices, 16 for masters)

Returns:

the updated Elo rating