BGonline.org Forums

Larsen/Silliman U.S. Backgammon Ranking

Posted By: Ken Larsen
Date: Sunday, 9 February 2014, at 8:04 p.m.

My latest ranking of U.S. players can be seen here: http://home.roadrunner.com/~kenlarsen/bgUSrating.htm

Henceforth, I’m calling it the “Larsen/Silliman U.S. Backgammon Ranking” to distinguish it from other rankings that people may create. “Silliman” refers to Barry Silliman who wrote software to read USBGF loaded draw sheets that had been collected since 2009. Kudos to him for that work!

The latest ranking treats the current year as the most recent 12 month period going backwards from January 21, 2014. The previous iteration was calendar year based. In a few weeks we hope to add the San Antonio tournament and repost. As we progress through 2014, new tournaments from 2014 will be added, and old ones from 2009 will be dropped.

We’ve changed a couple of the “fudge factors” that we employed. Previously “number of weighted events” had to be 75 before the x value maxed out at 1.000. We concluded that 75 was too high as fewer than 1% of all ABT entrants had 75. We reduced the 75 to 40.

We welcome feedback from the math professionals regarding our choices.

Hopefully this posting will motivate people to either endorse it or derive something else ... culminating someday in a universally adopted world ranking system. I look forward to that day.