The parent is talking about TrueSkill 2 [0], while the trueskill Python library you linked currently only supports the original TrueSkill algorithm [1][2]. True

The parent is talking about TrueSkill 2 [0], while the trueskill Python library you linked currently only supports the original TrueSkill algorithm [1][2]. TrueSkill 2 takes into account individual scores of players in order to weigh the contribution of each player to each team. The idea is that this allows TrueSkill 2 to converge faster for new players. [0] https://www.microsoft.com/en-us/research/publication/trueskill-2-improved-bayesian-skill-rating-system/ https://www.microsoft.com/en-us/research/publication/trueski... [1] https://github.com/sublee/trueskill/issues/27 https://github.com/sublee/trueskill/issues/27 [2] https://www.microsoft.com/en-us/research/project/trueskill-ranking-system/ https://www.microsoft.com/en-us/research/project/trueskill-r...