Cash game. Black to play.

Hi,

you have a total of 4 (6/2) + 12 (2x7/1) + 7 (8/1) + 3 (24/21) = 26 pips to play before you have to throw a six
So within 4 moves you have to throw a six.
P(no 6 in 4 moves) = (25/36)^4 = about 25%.
On the other hand the chance of red throwing 2 fours within 4 moves = P(2|4) = 4!/2! x (11/36)^2 X (25/36)^2 =
about = 6 x 1/9 x 4/9 = 24/81 = 30%.
Of course there are also some pick and pass moves as soon as red enters one 4.
And there are gammons for black. But after crunching there are gammons for red, thouh less than for black.
So, i'd say double take.

If cubed here as red, I am passing pretty quickly, I think. If black escapes I will have three checkers in the air and with all those checkers in the outer board to bring home red is getting gammoned a lot. Also if red does end up with three checkers on the bar black will have more time than usual to extricate the last checker, and can afford to crunch some and still get out before red has entered all checkers from the bar.

I'm wondering if this might be too good, but seems a bit risky playing on, and for all practical purposes I would double anyway praying for a take.

But these prime positions can be difficult and you can often take more than you would think, so I might be off here, but I think there is simply too many gammon loses.

Look at this: http://graswurzel-backgammon.org/200...gammon/#more-5

The position above might be something for the whopper king contest. No word without my RO. But a guess: maybe a beaver?!

I like a double here even though you are facing a 5 prime. You have pretty good odds to cover the blot in the home board and you already have one checker on the edge of the prime and you'll probably hit the blot on the 15 point. You have a real good edge in the race and might completely close out your opponent which should result in a lot of gammons. Red has some counterplay and I'm really not sure if red should take or drop. I probably drop this because the gammon chances are too high.

If you think this is TG, would you give without hesitation 2 points and the Cube?

1. I didn't say I think this is tg.
2. I wouldn't do anything without hesitation in a pos. where I have already said I could be way off.

3. I pretty much don't play props anyway

Over the board I thought this was one of the few spots I have encountered in backgammon where I could find relatively solid justifications for basically every cubing action. I'm leaning towards double/take now, but at the time thought it was possibly too good (although with thought/analysis I'm now convinced this is probably the worse of all the options), but also thought it could easily be a beaver if it was a take. On my low powered notebook which can't handle much so would be curious to see some numbers from a big roll out.

XG 3-ply rollout says borderline redouble/no redouble. Costs about .30 to pass.

Grunch. This looks like a solid double, with the threat of escaping and picking up a third checker. However, This also looks like a solid take. there just are not that many positions where there are two checkers behind a five prime, with this sort of timing that are drops. If the opponent rolls a non 6 this roll, the next sequence will be a sweat.

Double/take

XGID=bBAB-BCBA------accbbbA--A-:1:1:1:00:0:0:3:0:10


Analyzed in Rollout
No Double
Player Winning Chances: 58,91% (G: 46,33% B: 1,01%)
Opponent Winning Chances: 41,09% (G: 7,81% B: 0,32%)
Double/Take
Player Winning Chances: 58,47% (G: 45,75% B: 0,82%)
Opponent Winning Chances: 41,53% (G: 8,28% B: 0,33%)

Cubeless Equities: No Redouble=+0,570, Redouble=+1,098

Cubeful Equities:
No Redouble: +0,717 (-0,005)
Redouble/Take: +0,722
Redouble/Drop: +1,000 (+0,278)

Best Cube action: Redouble / Take

Rollout
7776 Games rolled with Variance Reduction.
Moves and cube decisions: 3 ply
Confidence No Double: ± 0,011 (+0,706<E<+0,728)
Confidence Double: ± 0,016 (+0,706<E<+0,737)

Double Decision confidence: 68,4%
Take Decision confidence: 100,0%

Duration: 4 hours 57 minutes

eXtreme Gammon Version: 1.21

XG gives also a "dice distribution": 65 64 63 66 53 62 61 33 43 above the mean equity, with 22 32 41 42 51 11 31 52 21 55 same or a little below and only 44 and 55 destroyer. Joker 16,7% Antijoker 5,6%.

If you looke at the confidence interval, even 7776 trials are not enough.

In a mixed chouette, i think a strong double, but clear take. You can expect a pass from Colonel Whiteflag. Be aware if there are only Donald Dangers. Heads up against a strong player, i would wait a roll, otherwise ship it over. Beaver is surely a tilting insight.