Rating-Systems
19 posts
Twelve Rating Systems, Walked Forward Through Eight Seasons
Do rating systems built for college football beat ones built for chess at predicting college football? Six thousand games, one week at a time.
Scoring a Three-Outcome Predictor
A rating system gives you one number, and a draw is a third outcome that number cannot express. What that does to your accuracy, measured on 40,000 chess games.
Incremental and Global Fit Are Two Different Products
Elo nudges after every result. Massey re-solves the whole season. The choice decides your cold start, your reproducibility, and what a rating even means.
Whole-History Rating: Ratings With a Past Tense
Every other rating system tells you how good a competitor is now. WHR tells you how good they were on any day, using everything learned since.
Margin of Victory: Massey and Pythagorean
Two rating systems that read the scoreboard instead of just the result, and three things that turned up when I interrogated how they use it.
What Uncertainty Buys a Rating System
Glicko, Glicko-2 and TrueSkill all track how sure they are of a rating. What that second number does to a prediction, and whose uncertainty moves it.
Bradley-Terry: Maximum Likelihood Ratings on an Elo Scale
Bradley-Terry fits every comparison at once instead of nudging after each game. Adding it to elote, and the four design choices that made it usable next to Elo.
Rating Systems Compared: Choosing the Right Algorithm
A head-to-head comparison of Elo, Glicko, TrueSkill, DWZ, Colley Matrix and other rating systems. Know when to use each algorithm.
Ensemble Rating Systems: Combining the Best of All Worlds
Combine multiple rating algorithms like Elo, Glicko, and TrueSkill to get better predictions. Learn how Elote's ensemble approach works.
The Colley Matrix: A Linear Algebra Approach to Ratings
The Colley Matrix uses linear algebra to solve for optimal ratings simultaneously. Originally designed for college football rankings.