New WESPA ratings system launched

The WESPA ratings system has been the cornerstone of WESPA's efforts to globalize tournament Scrabble, enabling players to know exactly where they stand at the international level on a consistent basis and not just in terms of a single tournament.  Over the last few years, the Aardvark tool has brought the ratings system online, offerring thousands of Scrabble players worldwide the unprecedented ability to analyse historical tournament data in detail and has proved to be the most popular section on the WESPA site.

Behind the scenes, a tremendous amount of effort has been put by the WESPA Tournaments and Ratings Committee into not only maintaining the system and incorporating new data, but also improving the system itself so that it best reflects tournament prowess.  With that in mind the committee has released its first major overhaul of the system since inception, with several known issues faced by the old system remedied, and has made the new system available online through Aardvark.  Edward Okulicz, WESPA Tournaments and Ratings Committee member and chief architect of the Aardvark system, released the following official announcement on May 28th 2012:

As some of you know, this year WESPA decided to revise its ratings system.  The task was designed to make ratings fairer, particularly for new players in the system, of which WESPA's system has more than most national systems as more players partake in internationally-rated tournaments for the first time.  With the upgrade of Aardvark to take into account the new ratings having been previewed last week, many people have noticed that the ratings on the site have changed.  I can now announce that these ratings are official from today.

The major changes are:

The result of this is a stabler, fairer ratings system, and one that has increased the capacity and lifespan of the original WESPA ratings system through a number of smaller fixes and changes.

Some players may be disappointed with the new ratings because their rating and rank have gone down.  Indeed, this will be true for many players in the system. The old system had shortcomings that some players' ratings benefited from.  The correction of these flaws may have a dramatic effect on some people's ratings.  The generosity of the previous probability curve to the lower-rated player, the poor way the ratings system handled novices and near-novices in the system, and the inaccuracies in rating long tournaments are examples of causes of inaccurate ratings for a number of players.  As a member of the Tournaments and Ratings Committee, I stand behind the new calculations, and believe that those whose ratings have dropped or increased significantly have had their rating changed to a level that better reflects their performance.

Old ratings have been archived and displayed for posterity. Between 1993 and 2003, these ratings are displayed as "official".  From 2004 onwards, the new calculations are what appears in results pages.  Between 2004 and 2011, the legacy ratings can be viewed from tournament listing searches.

The full list of international rankings can be accessed here.  For more detailed analysis, use Aardvark's advanced search tool

June 2012