Game 1, move 5: Herd Cube Decision

[diane]

Position ID: 4G3wAlDMZuKAIg
Match ID: cAmgAAAAAAAA

giles danced again with 5-3, and I think we should stop for a moment and think about a potential cube.

[NIHILIST]

Spoiler

Take a shake, it could be this is too good to cube. Gammons still pay double, don't they ?

[close]

Bob

[stiefnu]

Spoiler

Gammons still pay double, don't they ?

And a point's a point.  Though clear favourites, we only have a 3-pt board and plenty of work to do with our three back men.  I say ship it and get to 4 away.

[close]

[NIHILIST]

In our chouette I'd buy games from wimps like you.

Bob

[stiefnu]

Spoiler

LOL, as they say in these parts. Here, we're in a match. If we were in a chouette, we'd be playing a money game, when different considerations apply and playing on would doubtless have been the way to go.

[close]

Steve

[NIHILIST]

Playing on in a money game would NOT be the way to go. Since you can't gammon opponents without turning the cube, theres no reason to play on.

As regards the situation at hand, we have a better board, he has no anchor, he has 1 on the bar, he has a vulnerable blot. All these seem to suggest we play on for a gammon. If he anchors up on his next roll, cashing might be best, but it seems we have a free roll here.

Bob

[stiefnu]

Ooops! Crucial word 'not', carelessly omitted in error from my last post. Obviously it would be pointless to play on for a gammon in an un-cubed money game. Still reckon it was Ok to cube in this match though.

Steve

[ah_clem]

I'm late to the party here - just got back from spending a week riding horses in the Arizona desert, but it appears the Herd has done well in my absence.

Spoiler

We've still got some work to do to get our three stragglers around, and with only nine checkers in the zone blitzing is unlikely to pan out.  But, we've got the better board, a man on the roof and a blot to aim at. We're ahead in position, race, and threats which should make it a cash.  The question for us is whether it's too good to double.

I'm not entirely sure,  but I'll push the cube - maybe he'll take it. If not, we're at 4 away which is not much worse than three away - at this match score playing on for gammon doesn't give us all that much bang. 

And now that the vote is in, giles has made his decision, and I've spewed my $.02, I'll start a rollout.

[close]

[ah_clem]

rollout

Spoiler

2-ply analysis and 0-ply rollout are in agreement here, so we probably don't need a more thorough rollout, but I'll probably do one anyway.

The take decision is actually rather close, which is a bit of a surprise to me -  the pass seemed clear, so I need to think about that some more.   But the double decision is clear - holding the cube is a whopper.  Basically, we win a fair number of gammons here, but not enough to justify playing on. The rule of thumb is that you need to win twice as many gammons as losses to justify playing on, and we only win 30% gammmons vs 34% losses. And at this match score where a cash gets us to 4-away, we probably need more than a factorof two to play on.

Did we miss a cube?  I wasn't paying attention, so I can't say - need to look at it...








Cube analysis
Rollout cubeless equity  +0.614 (Money:  +0.586)

Cubeful equities:
1. Double, pass         +1.000
2. Double, take         +1.017  ( +0.017)
3. No double            +0.846  ( -0.154)
Proper cube action: Double, pass

Rollout details:
Centered 1-cube:
  0.668 0.299 0.019 - 0.332 0.065 0.004 CL  +0.614 CF  +0.846
[0.002 0.002 0.001 - 0.002 0.001 0.001 CL   0.005 CF   0.013]
Player gnubg owns 2-cube:
  0.672 0.292 0.018 - 0.328 0.067 0.006 CL  +1.336 CF  +1.017
[0.002 0.003 0.002 - 0.002 0.001 0.001 CL   0.016 CF   0.022]
Full cubeful rollout with var.redn.
1296 games, Mersenne Twister dice gen. with seed 888372887 and quasi-random dice
Play: 0-ply cubeful [expert]
Cube: 0-ply cubeful [expert]

[close]

[diane]

It appears the Herd has done well in my absence.

Actually, the Herd had a word with me, and said it would a cold day on the ski slope before they would let you anywhere near the dice again....

Did we miss one...hope not, After I did the last move, I suddenly thought I probably should have asked then, but it was a bit late.  Let me know.

[ah_clem]

Did we miss one...hope not, After I did the last move, I suddenly thought I probably should have asked then, but it was a bit late.  Let me know.

Anytime I have a cash I wonder whether I missed a cube, so the thought crossed my mind here.  I've posted a rollout of the cube decision for the last move and it's not a cube - one could argue that it was close enough to have a vote, but I don't think it was.  In any case, we didn't miss a cube.

[ah_clem]

I posted this cube decision over at Stick's site for further commentary:

http://www.bgonline.org/forums/webbbs_config.pl?noframes;read=97085#97085

2-ply rollout is available there.

Spoiler

Stick and Nack saw right away that this was a pass at score, but it would be a take for money.  Usually early match scores play just like money play, but there are exceptions, and this is one.  Here, the position is quite gammonish (but not gammonish enough to justify playing on for the gammon) and doubled gammons are particularly valuable at 5-away 5-away since it gets us to crawford.  And from giles' perspective, the prospect of losing a doubled gammon is enough to decline the cube offer.

Interesting position...

[close]