Historical Chess Ratings – dynamically presented

Rod Edwards historical chess ratings

The Edo Historical Chess Rating system is a novel approach to the retroactive rating of chess players over time. Ratings over the whole period are calculated simultaneously by an iterative method (Bradley-Terry). Similar iterative methods have been used before (by Elo, for example, to initialize the FIDE ratings in 1970), but in a static way, to estimate playing strengths at a particular time.

The Edo system uses the simple (but new when first developed, in 2004) idea of treating a single player in different years as separate players, and positing hypothetical drawn self-games between the same player in consecutive years. For example, Staunton-1845 is considered to have played a 30-game match with Staunton-1844 with a resulting score of 15-15. This keeps each player's rating from changing too dramatically in response to every year's performance, which is subject to random variations. Then, an adjustment is made to account for a known underlying distribution of playing strengths of all chess players in general - very high or very low ratings being inherently less likely than average ones. This adjustment decreases the effect of anomalous scores for players with very few game results.

More about the Edo historical rating system

Before we present the video that so fascinated us, here are some caveats that Rod Edwards expressed:

The video is misleading in presenting the early players (pre-1840 or 1850, say) by their ranking, as if I were claiming that this were based on complete information. I try to make it clear on my website that, because I have definite results for only a few early players, many strong players are simply missing in those years, and the ratings that are given are very uncertain (large variance). So I would certainly not claim that Alexandre, for example, was the best player in the world in 1818, only that he has the highest very tentative Edo rating of the few players I can rate in that year. Deschapelles was certainly stronger, and so probably was Petrov, despite his appearing lower on the list that year. So it is clear that the early rating lists especially are very tentative, and very incomplete.

Note also that my ratings are continually updated as I find new information. In my next update for example, Kolisch's rating curve will change and, even more dramatically, John Cochrane's, based on new information I've just found.

Here, without further ado, is the video presentation that fascinated us:

To get the proper effect switch to full screen and lean back to enjoy the six-minute presentation

And this is a five-minute presentation of the world's best Go players (including AlphaGo)

We have not (yet) been able to track down the authors of the above animations. The name given is "Abacaba" and the profiles in YouTube and Facebook are "We make videos about data and math."

We assume they are the Huang twins Michael and Cary, pictured on the right at the age of fourteen when, in 2012, they made this truly incredible Scale Of The Universe video, which shows the size of things from the entire uiniverse to quantum foam. Not just the video, also a "Scale of the Universe" animation in which you can actively scroll to get from one end of the range to the other. They spent a year and a half making it. They have also made tons of Flash videos.

Addendum: In the meantime Michael Huang contacted us. "Abacaba is a YouTube channel of my twin brother Cary Huang and me," he wrote, "although the ratings video was made by Cary alone. We are two teenagers from California making these videos in our free time. Cary wrote the code for the whole video (including the graphs and labels) in Processing, a programming language for making visualizations. Since the three sources (linked in the description of the video) each span a short period of time, he had to stitch them together, crossfading during the periods where they overlapped."

Rod Edwards is a Professor of Mathematics at the University of Victoria, Canada. While his academic research mainly deals with the theory of network dynamics in biological contexts, he has always had a fascination for chess and its history. Combining these two interests led him to develop a rating theory based on a network of interactions between chess players over time, and, as a spare-time project, he has been collecting historical data on chess players and results of their contests in the 19th and early 20th centuries. The result is the Edo Historical Chess Ratings project, continually being updated at http://www.edochess.ca.