Justin Buser
09-11-2005, 12:08 AM
Microsoft have released a very technical document that outlines how the ranking system for Xbox Live will work. Called the "TrueSkill Ranking System", it is based on 50 different skill levels and a heap of complicated equations.
Most games have at their root a metric for judging whether the game’s goals have been met. In the case of matches involving two or more players (“multiplayer matches”), this often includes ways of ranking the skills of match participants. This encourages competition between players, both to “win” individual matches, and to have their overall skill level recognised and acknowledged in a broader community. Players may wish to evaluate their skills relative to people they know or relative to potential opponents they have never played, so they can arrange interesting matches. We term a match “uninteresting” if the chances of winning for the participating players are very unbalanced – very few people enjoy playing a match they cannot win or cannot lose. Conversely, matches which have a relatively even chance of any participant winning are deemed “interesting” matches.
Many ranking systems have been devised over the years to enable leagues to compare the relative skills of their members. A ranking system typically comprises three elements:
A module to track the skills of all players based on the game outcomes between players ("Update").
A module to arrange interesting matches for its members (“Matchmaking”).
A module to recognise and potentially publish the skills of its members (“Leaderboards”).
In particular, the ELO ranking system has been used successfully by a variety of leagues organised around two-player games, such as world football league, the US Chess Federation or the World Chess Federation, and a variety of others. In video games many of these leagues have game modes with more than two players per match. ELO is not designed to work under these circumstances. In fact, no popular skill-based ranking system is available to support these games. Many one-off ranking systems have been built and are in use for these games, but none of them is general enough to be applied to such a great variety of games.
Read all the technical details at MS Research (http://www.research.microsoft.com/mlp/trueskill/default.aspx)
Most games have at their root a metric for judging whether the game’s goals have been met. In the case of matches involving two or more players (“multiplayer matches”), this often includes ways of ranking the skills of match participants. This encourages competition between players, both to “win” individual matches, and to have their overall skill level recognised and acknowledged in a broader community. Players may wish to evaluate their skills relative to people they know or relative to potential opponents they have never played, so they can arrange interesting matches. We term a match “uninteresting” if the chances of winning for the participating players are very unbalanced – very few people enjoy playing a match they cannot win or cannot lose. Conversely, matches which have a relatively even chance of any participant winning are deemed “interesting” matches.
Many ranking systems have been devised over the years to enable leagues to compare the relative skills of their members. A ranking system typically comprises three elements:
A module to track the skills of all players based on the game outcomes between players ("Update").
A module to arrange interesting matches for its members (“Matchmaking”).
A module to recognise and potentially publish the skills of its members (“Leaderboards”).
In particular, the ELO ranking system has been used successfully by a variety of leagues organised around two-player games, such as world football league, the US Chess Federation or the World Chess Federation, and a variety of others. In video games many of these leagues have game modes with more than two players per match. ELO is not designed to work under these circumstances. In fact, no popular skill-based ranking system is available to support these games. Many one-off ranking systems have been built and are in use for these games, but none of them is general enough to be applied to such a great variety of games.
Read all the technical details at MS Research (http://www.research.microsoft.com/mlp/trueskill/default.aspx)