Newsletter for 13 April 2004

Is Tuesday the 13th unlucky?

On Tuesday, 13 April 2004, the Backgammon Club of San Diego met, and we held yet another tournament. We welcomed three new players to the mix: Randy Barning, and the father-son duo of Mozafar Behrooznia and Rasheed Behrooznia.

Tournament News

11 people entered a 16-player bracket on Tuesday night. We had the following tournament results:

First place: Cyrus Mobedshahi
Second place: Adrian Costa
Third place: Bruce Haight and Mark Weiner (split)
Blitz winner: Ryan Knowles

Current Master Points Standings

Cyrus' victory moved him from 8th place up to 5th place, while Adrian's 2nd place finish moved him past Tom Fahland into 3rd place overall. Jason Lee remains in first place overall, but Bruce picked up a point and with a victory can pass Jason for the overall lead. Ryan won a blitz to pick up his first master point of the year. We now have MORE than 16 players with master points -- so at some point, there may be quite a battle to see who qualifies for the Tournament of Champions!

 1. Jason Lee        39
 2. Bruce Haight     32
 3. Adrian Costa     29
 4. Tom Fahland      26
 5. Cyrus Mobedshahi 18
 6. Osman Guner      15
 7. Sho Sengoku      12
 8. Fred Kamgar      11
 9. Marcia Karen      9
10. Eric Sedehi       8
11. Henry Chaboki     4
12. Mark Weiner       3
13. Ryan Knowles      2
13. Chris Rosin       2
13. Greg Kopp         2
16. Maira Costa       1
16. Sam Mehri         1

The point leader at the end of the year will be named the BCSD Player of the Year, and the top 16 in the Master Point standings will be invited to the 2004 BCSD Tournament of Champions, to be held in early 2005.

Problem of the Week

Cube or play on?

+-24-23-22-21-20-19-+---+-18-17-16-15-14-13-+

| |

| | 1X| |

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| 4 |

+--1--2--3--4--5--6-+---+--7--8--9-10-11-12-+

Score tied 0-0 in a 5 point match. Pip counts: Black 67, White 73
Position ID: 3x1DAEDb24EABA Match ID: UgmgAAAAAAAA

Last Week's Problem of the Week

The previous week's problem was the following position:

+-24-23-22-21-20-19-+---+-18-17-16-15-14-13-+

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| | | |

| |

| 2 |

| | 1O| |

+--1--2--3--4--5--6-+---+--7--8--9-10-11-12-+

Money game. Pip counts: White 24, Black 100
Position ID: BQBAsM2mgQAEAA Match ID: UQkAAAAAAAAA

This position turned out to not only be a take for White, but a beaver! Then we asked how many White checkers can you put on the ace point and still have a take?

Here's the position with eleven checkers on the ace point:

+-24-23-22-21-20-19-+---+-18-17-16-15-14-13-+

| |

| | | |

| |

| 2 |

| | 1O| |

+--1--2--3--4--5--6-+---+--7--8--9-10-11-12-+

Pip counts: White 34, Black 100
Position ID: /xcAAME2mwYCEA Match ID: UQkAAAAAAAAA

And GNU says that White can still take in this position:

Cube decision

Rollout cubeless equity +0.492

Cubeful equities:

1. Double, take +0.947

2. Double, pass +1.000 +0.053

3. No double +0.751 -0.195

Proper cube action: Redouble, take

Rollout details

Win W g W bg Lose L g L bg Cubeless Cubeful

Player Black owns 2-cube 0.777 0.000 0.000 - 0.223 0.062 0.000 +0.492 +0.751

Standard error 0.000 0.000 0.000 - 0.000 0.000 0.000 0.000 0.001

Player White owns 4-cube 0.791 0.000 0.000 - 0.209 0.061 0.000 +1.043 +0.947

Standard error 0.000 0.000 0.000 - 0.000 0.000 0.000 0.001 0.001

Truncated cubeful rollout (depth 11) with var.redn.

46656 games, Mersenne Twister dice gen. with seed 961826240 and quasi-random dice

Play: 0-ply cubeful [expert]

Cube: 0-ply cubeful [expert]

But if we put just one more on the ace point:

+-24-23-22-21-20-19-+---+-18-17-16-15-14-13-+

| |

| | | |

| |

| 2 |

| | 1O| |

+--1--2--3--4--5--6-+---+--7--8--9-10-11-12-+

Pip counts: White 35, Black 100
Position ID: /y8AAIJtNg0EIA Match ID: UQkAAAAAAAAA

GNU says to drop this one:

Cube decision

Rollout cubeless equity +0.528

Cubeful equities:

1. Double, pass +1.000

2. Double, take +1.036 +0.036

3. No double +0.767 -0.233

Proper cube action: Redouble, pass

Rollout details

Win W g W bg Lose L g L bg Cubeless Cubeful

Player Black owns 2-cube 0.791 0.000 0.000 - 0.209 0.053 0.000 +0.528 +0.767

Standard error 0.000 0.000 0.000 - 0.000 0.000 0.000 0.000 0.001

Player White owns 4-cube 0.807 0.000 0.000 - 0.193 0.053 0.000 +1.123 +1.036

Standard error 0.000 0.000 0.000 - 0.000 0.000 0.000 0.001 0.001

Truncated cubeful rollout (depth 11) with var.redn.

46656 games, Mersenne Twister dice gen. with seed 961826496 and quasi-random dice

Play: 0-ply cubeful [expert]

Cube: 0-ply cubeful [expert]

A nice position to explore! It's always interesting to look at a position, and then modify it to see how it changes... this is where the bots are useful -- these rollouts were performed simultaneously overnight. Gotta keep GNU working hard in the wee hours!

See you next week! Keep tossing those cubes,
J. Lee

Output generated by GNU Backgammon 0.14-devel (HTML Export version 1.123)