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Comparison of Various Backgammon Rating Systems

System Pros Cons Comments
  • Accounts for the difficulty of opponents.
  • Doing well at a tournament with great players (who have high Elo's) will boost a player's Elo higher than playing well in a tournament with lesser skilled players.
  • Elo is used in other contests and is familar to many people.
  • Places more weight on recent events.
  • Doesn't decay with age.  If a person doesn't play for a protracted length of time, their Elo remains the same.
  • Doesn't remove luck factor.
  • Different stengths of player pools can adversely effect Elo.  An extreme example is this story of Claude Bloodgood.
  • Should be restricted to live tournaments only
Giants List
  • Has been in existence since 1993
  • Only done every 2 years
  • Popularity contest
  • Votes are not weighted by the attendance of the voters.  If a voter attended only one tournament their vote is weighted the same as someone who attended 10 tournaments. 

  • No matter how many tournaments a voter plays in, their purview of worldwide backgammon players is very limited. 

Opinions of Ken Larsen:

  • (November 23, 2017) On the home page of their website, the Flint Michigan club asks "Who are the best backgammon players in the World?" and then links to the Giants list.  To me, that answers the question about what the Giants list is all about.  People who are promoters of backgammon ... or instructors ... shouldn't be on the list unless they merit inclusion by skill (tournament wins or long time PR achievement).   Golf analogy:  Butch Harmon (consenus # 1 instructor) shouldn't be listed in the World Rankings.  [He isn't.]  Golf world rankings is all about performance in major tournaments over the most recent two years.
  • (November 24, 2017) To correct the "limited purview" issue, I recommend that Giant List voters consider voting for the top players based on a combination of the player's PR as documented on the BMAB and the player's major tournament achievements during the most recent two years.  For example, I recommend that Giant List voters exclude anyone whose PR in the BMAB is over 5.00 ... or maybe 6.00.  This would legitimize the Giants List if enough voters did this. 
Master Points
  • At least in the U.S.'s ABT system, the size of the field and the skill level of the tournament (Open, Advanced, or Novice) directly influence the quantity of points awarded.
  • Favors attendance
  • Can only go up
  • Doesn't decay with age
  • Doesn't remove luck factor.
  • Treats a 0-3 record and a 2-3 record in a tournament as the same.
  • Should be restricted to live tournaments only. 
  • An example is the ABT system in the U.S.
  • Limits the effects of attendance
  • Only looks at the last 5 years
  • Places more weight on recent years
  • Only considers main events
  • Currently is only used in the U.S., but it could be expanded to the rest of the world if agreement could be reached on the assignment of Master points worldwide.  This is not likely to happen.
  • Doesn't remove luck factor.
  • Treats a 0-3 record and a 2-3 record in a tournament as the same.
  • Is a derivative of Master Points.  It attempts to correct the flaws of the Master Points system.
  • Is restricted to live tournaments only
  • There are a lot of variables that could be tweaked:  number of years considered, weights of each year, weights assigned to attendance.
  • Limits the luck factor
  • Unlike Elo, Larsen-Silliman, or Master Points, players from different playing pools may be fairly compared.
  • The BMAB leader (Rick Janowski of the UK) pledges to remove players if they are idle (no tournament competition) for 18 months.
  • Labor intensive to derive
  • subject to cherry picking
  • Due to eXtremeGammon not being perfect, technical issues with calculating PR, and not considering an opponent's deficiencies, playing for a low PR is not the same as playing to win a match.
  • PR = eXtremeGammon's Performance Rating 
  • BMAB is restricted to live tournaments only. 
  • (November 23, 2017) To resolve the "labor issue", I advocate that tournament backgammon be played on computer tablets instead of on real boards.  See the "Solution: section of "Concerns about the future of tournament backgammon".

(February 22, 2016) Matt Cohn-Geier's assessment of the Giant's List, Elo, and error rate/PR:  Matt is currently Giant #5.

(November 23, 2017) Ken's opinion:  BMAB is the best ranking system listed here.  If the "labor issue" could be resolved and tournament PRs collected quasi-realtime, it would be a fabulous system ... providing real-time updates to a world ranking system.  That could really grow the game.  People would be excited and want to enter major tournaments which feed the BMAB. 

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