LEADER BOARD

    ELO Annual
Player Exp Rating Points Race
Tom Meyer 166 1543.83 50
Jay Karns 139 1532.35 37.5
Al Cantito 167 1546.19 36.5
Jim Sisti 175 1471.27 29
Sandy Sisti 159 1464.36 26.5
Gerhard Roland 46 1518.95 17
Ed Corey 122 1453.85 16.75
Ray Nelson 57 1496.19 15
Al Theriault 60 1511.83 14
Mark Denihan 17 1528.48 11
Ross Gordon 15 1526.77 10
Jim Stutz 21 1511.00 6
Adrian Costa 20 1518.28 4.75
Andy Fazekas 30 1500.55 4.75
Bill Porter 35 1494.21 3
Dan Whitney 20 1502.49 2
Mike Pollack 30 1485.59 2
Rob Roy 23 1477.80 1
Dave Mirto 21 1475.13 1
Frank V 37 1457.21 1
Terri White 10 1483.68 0

Updated 5/26/17

Annual Points Race Accrual Methodology

 

For each tournament event, Points are awarded to players as follows:

 

1.  A player receives 1 Point for each match they win

 

2.  Bonus Points are established based on the number of event participants and distributed thus:

 

A.  1st Place receives an amount equal to the total number of participants

 

B.  2nd Place receives an amount equal to one-half the total number of participants

 

C.  3rd Place (Optional) receives an amount equal to one-quarter the total number of participants

 

All tournament event points awarded to a player are added to their annual cumulative total.

 

FIBS Rating Formula*

 

These are the formulas used to determine the ratings of a player:

 

Let's say that two players P1 and P2 were playing a n-point match. The ratings of the players are r1 for P1 and r2 for P2 .

 

Let D = abs(r1-r2) (rating difference)

Let P_upset = 1/(10^(D*sqrt(n)/2000)+1) (probability that underdog wins).

Let P=1-P_upset if the underdog wins and P=P_upset if the favorite wins.

 

For the winner:

Let K = max ( 1 , -experience/400+2 )

The rating change is: 4*K*sqrt(n)*P

 

For the loser:

Let K = max ( 1 , -experience/400+2 )

The rating change is: -4*K*sqrt(n)*P

 

The 'experience' of a player is the sum of the lengths of all matches a player has finished. Every player starts with a rating of 1500 and an experience of 0.

 

*Thanks to FIBS (First Internet Backgammon Server) for providing the rating formula as part of their HELP menu.