• Score: Red (3-away), White (5-away)
Posted by Neil Kazaross [060104]

Red on roll, cube decision

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

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

Pip counts: White (Top): 64, Red (Bottom): 39

In the quarter finals in the conso, vs California's Doug Mayfield, I fell from grace with a big missevaluation of this position.
Your task is to avoid making the same error that I did. What am I supposed to do with the cube and why ?
-- Neil Kazaross

I'm only getting White winning 13-14% here (though I may be underestimating Red's open 4 and 5-points), so I take a big breath and send it over.
I drop as White.
-- Dean Gay

I would estimate that White will probably win just under 16% of the time.
Since White needs to win 15% at this score (5-away/1-away Cr. gives White 15% ME) to take and put the match on the line, and there is a fair amount of volatility on the next change, Red has a clear double.
White might or might not have a take, depending upon whether his estimate of his winning chances are.
-- Doug Doub

I would estimate that White's winning chances are less than 16% because White may be forced to run and with the 6-point open, hits do not necessarily win.
I would say White can win 16% of the time when he hits if White can stay next turn. So I'd double and drop.
-- Casper van der Tak

There are some horror rolls here, so I think I would have waited a roll. I guess White can hit a checker at least 15% of the games.
-- Oystein Johansen

I grossly undervalued my (Red's) position here and felt that White has about 18 to 19% winning chances.
Since in a position like this, Red can use the cube later, that is about what I need to have a borderline recube so I held off and rolled 3-3 and ginned the game, only to lose the match from 8-4 Crawford in 3 games.
My mistake was giving White too much credit for sleezy race wins and not taking enough into account of the fact that White's racing equity will be dropped if he stays and then must leave on 6's the following turn.
The gaps aren't that bad for the race since Red will likely waste on roll from misses and then have a very speedy board.

The rollout shows that a take is a +0.108 error with 13.7% winning chances for White. My failure to cube is wrong by .129 CPW if White passes and wastes a chance to get a bad take from him. I did know whether he was taking or not.
My logic on this position was faulty even after estimating that I had a borderline recube decision.
Since Doug Mayfield is a good player I should have recubed, even though I was certain his take was clear to give him a chance to screw up and pass.
However, I was so far off that I failed to recube a proper pass.
-- Neil Kazaross

GNU_0.14  2-ply/worldclass, cubeful, Kazaross Met

Cube action equity

Eval Cubeless equity:   0.715  ($ 0.716)

W: 85.7%    WG: 0.3%    LG: 0.0%

1. Redouble, pass 1.000

2. Redouble, take 1.071 (+0.071)

3. No redouble 0.875 (- 0.125)

Proper cube action: Redouble, pass

Snowie_4  3-ply/precise, cubeful, Snowie 2.1 Met

Cube action equity

Eval Cubeless equity:   0.735

W: 86.6%    WG: 0.3%    LG: 0.1%

1. Redouble, pass 1.000

2. Redouble, take 1.134 (+0.134)

3. No redouble 0.875 (- 0.125)

Proper cube action: Redouble, pass

GNU_0.14  3-ply/grandmaster, cubeful, Kazaross Met

Cube action equity

Eval Cubeless equity:   0.726  ($ 0.726)

W: 86.3%    WG: 0.1%    LG: 0.0%

1. Redouble, pass 1.000

2. Redouble, take 1.106 (+0.106)

3. No redouble 0.876 (- 0.124)

Proper cube action: Redouble, pass

2-ply/100%, cube: 2-ply/100%, Full, 828 games, Jacob/Trice Met

Cube action equity

Rollout Cubeless equity:   0.722  ($ 0.722)

W: 86.3%    WG: 2.1%    LG: 0.1%

1. Redouble, pass 1.000

2. Redouble, take 1.108 (+0.108)

3. No redouble 0.871 (- 0.129)

Proper cube action: Redouble, pass

[Volatility: 0.181]

• Score: Red (5-away), White (3-away)
   Posted by Gregg Cattanach  [071804]

   White on roll, cube decision

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

| |

|1 |

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

Pip counts: White (Top): 134, Red (Bottom): 186

I'd double and pass for money. White has just about everything going for him and will be fine even if Red makes a second anchor. Maybe it's even too good, but I'm far from sure of that and Red may take for money.
I'd still double at this score, but now I'm unsure about Red's decision. Red will at least have a well-timed ace-point game, and has decent chances at a second anchor or a fly-shot.
With the recube vig, which kills White's gammons, I'll take as Red.
-- Dean Gay

This is such an extremely difficult score when a good portion of White's advantage is based upon winning a gammon or even a backgammon. I thought about this for a long time today and, from my experience, I think the position is worth about .725 cubeless for money which would make this a BIG money pass.
To me it looks like White wins a gammon in at least 1/3 of all games and taking into account the fact that the gammon has a point of overage and the backgammon is useless, and that when Red recubes, White's take-point is 1/3 (with an added gammon cost of 1/3) I honestly am quite certain that Red has a clear take here at this score.
Note that the 5-point isn't closed yet and that Red has his 5-point and that White has two outfield blots. Therefore, Red has some tactical chances for a quick turn around.
Red's take is so easy that I wouldn't cube here vs any player who I felt would most likely accept (many will pass this, unaware of their immense recube leverage).
-- Neil Kazaross

Clear pass for money but a solid take at the score because of the overage on the gammons and the gammon canceling recube to 4.
Definitely a double because of the passes you'll get (including mine in the actual match).
-- Gregg Cattanach

GNU_0.14  2-ply/worldclass, cubeful, Kazaross Met

Cube action equity

Eval Cubeless equity:   0.824  ($ 0.724)

W: 70.2%  WG: 32.8%    LG: 5.4%

1. Double, take 0.935

2. Double, pass 1.000 (+0.065)

3. No double 0.862 (- 0.073)

Proper cube action: Double, take

Snowie_4  3-ply/precise, cubeful, Snowie 2.1 Met

Cube action equity

Eval Cubeless equity:   0.665

W: 68.6%  WG: 32.2%    LG: 5.9%

1. Double, take 0.929

2. Double, pass 1.000 (+0.071)

3. No double 0.846 (- 0.083)

Proper cube action: Double, take

GNU_0.14  3-ply/grandmaster, cubeful, Kazaross Met

Cube action equity

Eval Cubeless equity:   0.896  ($ 0.795)

W: 72.8%  WG: 34.6%    LG: 5.0%

1. Double, pass 1.000

2. Double, take 1.121 (+0.121)

3. No double 0.955 (- 0.045)

Proper cube action: Double, pass

SW4, 2-ply/precise cube: 3-ply, Full, 648 games, SW2.1 Met

Cube action equity

Rollout Cubeless equity:   0.675

W: 68.9%  WG: 31.6%    LG: 5.9%

1. Double, take 0.939

2. Double, pass 1.000 (+0.061)

3. No double 0.856 (- 0.083)

Proper cube action: Double, take

[Volatility: 0.118]

Next

Hosted by www.Geocities.ws