Othelloclub World Ratings is an Othello rating system based on Mark Glickman’s Glicko-2 algorithm. Chess.com, Lichess, and others also use the Glicko rating system.

The Glicko-2 rating system builds on the Elo algorithm by introducing a measure of rating uncertainty called the Rating Deviation (RD). A larger RD indicates lower confidence in a player’s rating and leads to greater rating volatility after each game. RD starts out high and decreases as a player competes in more matches, though it may rise again if the player’s volatility parameter σ (sigma) is large.

In the Othelloclub rating system, players begin with an initial rating of 1600, an RD of 350, and σ of 0.06. Players who have been inactive for two years or whose RD has not yet stabilized (i.e., is 100 or higher) are considered unofficial and excluded from the rating list. Global certification is granted by participating in a WOF-certified international tournament or by playing at least 5 games against globally certified rating holders. Before receiving global certification, players are treated as having local ratings: they are included in national rankings but excluded from world rankings.

The list of WOF-certified international tournaments is as follows.

• WOC (World Othello Championship)
• AOC (African Othello Championship)
• APOC (Asia-Pacific Othello Championship)
• EGP (European Grand Prix)
• EOC (European Othello Championship)
• NAOC (North American Othello Championship)
• SAOC (South American Othello Championship)
• WAOC (West Asian Othello Championship)

While there is an official rating system for World Othello Federation, I was curious to see how Othello would be rated under the Glicko-2 system, so I decided to run this unofficial rating system. I think it will be interesting to compare the results.

Lastly, I would like to express my gratitude to WOF for making their data available online, which allowed me to input a substantial amount of game data from 1991 to the present.