TrueSkill
Same skill estimate. Different certainty.
Interactive example · no real player data
The centre μ stays at 25. A narrower curve means more confidence. The dashed curve shows σ = 9. Conservative example: μ − 3σ = 7.
Educational preview · this method is coming soon
How it works About 1 min read
TrueSkill, developed by Microsoft Research for Xbox Live, is a Bayesian skill rating system that natively supports teams and free-for-all games with placements -- something Elo and Glicko cannot do.
How it works: Each player has a skill estimate (mu) and uncertainty (sigma). The conservative rating is mu - 3×sigma. After each match, a Bayesian update refines both values based on the outcome and the relative skills of all participants. It handles partial orderings, teams, and multi-player free-for-all matches.
When to use it: The most versatile advanced rating system. If your group plays FFA board games, team games, AND 1v1 games, TrueSkill is the only advanced rating that handles all three.
Watch out for: Computationally expensive, especially with large FFA fields. The mathematics are complex (factor graphs). Rating numbers aren't as intuitive as Elo (a "skill" of 25.0 ± 8.3 isn't as graspable as "1800 Elo").