Chess Ratings — Move Over Elo

databuff writes "Less than 24 hours ago, Jeff Sonas, the creator of the Chessmetrics rating system, launched a competition to find a chess rating algorithm that performs better than the official Elo rating system. The competition requires entrants to build their rating systems based on the results of more than 65,000 historical chess games. Entrants then test their algorithms by predicting the results of another 7,809 games. Already three teams have managed create systems that make more accurate predictions than the official Elo approach. It's not a surprise that Elo has been outdone — after all, the system was invented half a century ago before we could easily crunch large amounts of historical data. However, it is a big surprise that Elo has been bettered so quickly!"

Comments

umm

[buddyglass]

However, it is a big surprise that Elo has been bettered done so quickly!

Not really. Jeff Sagarin has had two systems of rating sports teams for a while now. One, ELO_CHESS, is based purely on win-loss, while the other, PURE POINTS, takes into account margin of victory. According to him, the latter is better at predicting future results. From his analysis:

In ELO CHESS, only winning and losing matters; the score margin is of no consequence, which makes it very "politically correct". However it is less accurate in its predictions for upcoming games than is the PURE POINTS, in which the score margin is the only thing that matters. PURE POINTS is also known as PREDICTOR, BALLANTINE, RHEINGOLD, WHITE OWL and is the best single PREDICTOR of future games.

Re:Submission error

[databuff]

The Elo Benchmark was submitted a second time. I wrote to Sonas about this. Apparently the rating system has to be seeded. He tried a different approach to calculating seed ratings and this performed better - pushing him one place higher in the rankings.

Elo Anecdote

[afabbro]

Not relevant specifically to this story, but I always laugh at the story of how a prisoner manpiulated the Elo system via closed pool ratings inflation.

Short summary: said prisoner only played against other prisoners, who he'd trained. Due to careful scheduling of the games, he rose from his true strength (probably sub-master) to being the second-highest rated played in the U.S. in 1996.