Details on XBox TrueSkill Ranking System

rupert0 writes "A research paper on the Microsoft website gives an insight into the way that gamers will be ranked on the new-style Xbox Live. The paper outlines some existing ranking systems, as well." From the article: "The TrueSkill(TM) ranking system is a skill-based ranking system designed to overcome the limitations of existing ranking systems, and to ensure that interesting matches can be reliably arranged within a league. It uses a technique called Bayesian inference for ranking players. Rather than assuming a single fixed skill for each player, the system characterises its belief using a bell-curve belief distribution (also referred to as Gaussian) which is uniquely described by its mean (speak [mju:]) ("peak point") and standard deviation (speak [sigma])("spread")."