XGID=-CBC-BB-B--aca-a-cbd-----A:1:1:1:22:0:0:0:0:10

Score is X:0 O:0. Unlimited Game
+13-14-15-16-17-18------19-20-21-22-23-24-+
| O O O O | | O |
| O O | | O |
| O | | O |
| | | O |
| | X | |
| |BAR| |
| | | |
| | | |
| O | | X X | +---+
| O X | | X X X X X | | 2 |
| O O X | | X X X X X | +---+
+12-11-10--9--8--7-------6--5--4--3--2--1-+
Pip count X: 79 O: 137 X-O: 0-0
Cube: 2, X own cube
X to play 22

---
Tim Chow

XGID=-CBC-BB-B--aca-a-cbd-----A:1:1:1:22:0:0:0:0:10

Score is X:0 O:0. Unlimited Game
+13-14-15-16-17-18------19-20-21-22-23-24-+
| O O O O | | O |
| O O | | O |
| O | | O |
| | | O |
| | X | |
| |BAR| |
| | | |
| | | |
| O | | X X | +---+
| O X | | X X X X X | | 2 |
| O O X | | X X X X X | +---+
+12-11-10--9--8--7-------6--5--4--3--2--1-+
Pip count X: 79 O: 137 X-O: 0-0
Cube: 2, X own cube
X to play 22

Of course the first two 2's are bar/21, "coming under the gun."
X is trying to bring home the straggler and his board is much
stronger than O's. The subject line was intended to disguise
slightly the real question, which is how to play the remaining
two 2's.

I was surprised to see that XG favors 6/4(2), since normally
the 6pt is such a good point to have. I think the point is that
with average luck, X is going to have to crunch further before
he brings his straggler home, and we should be thinking about
how to preserve a good board for as long as possible. If X plays
8/4 instead, chances are he'll have to break a home-board point
soon, so the main alternative to 6/4(2) is 8/6(2). 8/6(2) gives X
fewer spare pips to play before he has to break a home-board point,
but it also kills sixes. Not an easy tradeoff to assess IMO, but
as I said, XG favors 6/4(2).

1. Rollout¹ Bar/21 6/4(2) eq:+0.308
Player: 52.64% (G:19.08% B:0.09%)
Opponent: 47.36% (G:2.74% B:0.06%)
Confidence: ±0.008 (+0.300..+0.316) - [100.0%]

2. Rollout¹ Bar/21 8/6(2) eq:+0.254 (-0.054)
Player: 50.75% (G:18.35% B:0.06%)
Opponent: 49.25% (G:3.33% B:0.09%)
Confidence: ±0.008 (+0.246..+0.262) - [0.0%]

3. Rollout¹ Bar/21 8/4 eq:+0.222 (-0.086)
Player: 49.58% (G:18.77% B:0.10%)
Opponent: 50.42% (G:3.74% B:0.10%)
Confidence: ±0.010 (+0.212..+0.232) - [0.0%]

4. Rollout¹ Bar/21 8/6 3/1 eq:+0.221 (-0.087)
Player: 50.13% (G:17.25% B:0.06%)
Opponent: 49.87% (G:3.78% B:0.09%)
Confidence: ±0.008 (+0.213..+0.230) - [0.0%]

¹ 1296 Games rolled with Variance Reduction.
Dice Seed: 271828
Moves: 3-ply, cube decisions: XG Roller

eXtreme Gammon Version: 2.19.211.pre-release

---
Tim Chow

On 11/13/2022 9:17 AM, Timothy Chow wrote:
> XGID=-CBC-BB-B--aca-a-cbd-----A:1:1:1:22:0:0:0:0:10
>
> Score is X:0 O:0. Unlimited Game
>  +13-14-15-16-17-18------19-20-21-22-23-24-+
>  | O     O     O  O |   | O                |
>  |             O  O |   | O                |
>  |             O    |   | O                |
>  |                  |   | O                |
>  |                  | X |                  |
>  |                  |BAR|                  |
>  |                  |   |                  |
>  |                  |   |                  |
>  | O                |   |          X     X | +---+
>  | O           X    |   | X  X     X  X  X | | 2 |
>  | O  O        X    |   | X  X     X  X  X | +---+
>  +12-11-10--9--8--7-------6--5--4--3--2--1-+
> Pip count  X: 79  O: 137 X-O: 0-0
> Cube: 2, X own cube
> X to play 22

With X's strong board, loose hits are not so advantageous for O and may
well be wrong. 23/21 exposes a quadruple shot, but not all that many are
POH. Seems like the game plan is to run or hit a shot and staying back
on the 23 will make it more likely that X's nice board will crack.

bar/21 8/6(2)

On Tuesday, November 15, 2022 at 8:19:16 AM UTC-5, Tim Chow wrote:
> XGID=-CBC-BB-B--aca-a-cbd-----A:1:1:1:22:0:0:0:0:10
>
> Score is X:0 O:0. Unlimited Game
> +13-14-15-16-17-18------19-20-21-22-23-24-+
> | O O O O | | O |
> | O O | | O |
> | O | | O |
> | | | O |
> | | X | |
> | |BAR| |
> | | | |
> | | | |
> | O | | X X | +---+
> | O X | | X X X X X | | 2 |
> | O O X | | X X X X X | +---+
> +12-11-10--9--8--7-------6--5--4--3--2--1-+
> Pip count X: 79 O: 137 X-O: 0-0
> Cube: 2, X own cube
> X to play 22
> Of course the first two 2's are bar/21, "coming under the gun."
> X is trying to bring home the straggler and his board is much
> stronger than O's. The subject line was intended to disguise
> slightly the real question, which is how to play the remaining
> two 2's.
>
> I was surprised to see that XG favors 6/4(2), since normally
> the 6pt is such a good point to have. I think the point is that
> with average luck, X is going to have to crunch further before
> he brings his straggler home, and we should be thinking about
> how to preserve a good board for as long as possible. If X plays
> 8/4 instead, chances are he'll have to break a home-board point
> soon, so the main alternative to 6/4(2) is 8/6(2). 8/6(2) gives X
> fewer spare pips to play before he has to break a home-board point,
> but it also kills sixes. Not an easy tradeoff to assess IMO, but
> as I said, XG favors 6/4(2).
>
> 1. Rollout¹ Bar/21 6/4(2) eq:+0.308
> Player: 52.64% (G:19.08% B:0.09%)
> Opponent: 47.36% (G:2.74% B:0.06%)
> Confidence: ±0.008 (+0.300..+0.316) - [100.0%]
>
> 2. Rollout¹ Bar/21 8/6(2) eq:+0.254 (-0.054)
> Player: 50.75% (G:18.35% B:0.06%)
> Opponent: 49.25% (G:3.33% B:0.09%)
> Confidence: ±0.008 (+0.246..+0.262) - [0.0%]
>
> 3. Rollout¹ Bar/21 8/4 eq:+0.222 (-0.086)
> Player: 49.58% (G:18.77% B:0.10%)
> Opponent: 50.42% (G:3.74% B:0.10%)
> Confidence: ±0.010 (+0.212..+0.232) - [0.0%]
>
> 4. Rollout¹ Bar/21 8/6 3/1 eq:+0.221 (-0.087)
> Player: 50.13% (G:17.25% B:0.06%)
> Opponent: 49.87% (G:3.78% B:0.09%)
> Confidence: ±0.008 (+0.213..+0.230) - [0.0%]
>
> ¹ 1296 Games rolled with Variance Reduction.
> Dice Seed: 271828
> Moves: 3-ply, cube decisions: XG Roller
>
> eXtreme Gammon Version: 2.19.211.pre-release
>
> ---
> Tim Chow

Of course the second two twos are 4(2)....other than the as mentioned potential lessening of crunching, you will get shots immediately sometimes. Offhand I'm sure there's a big swing if the opponent rolls [65 61] and one was silly enough to slot the four point. Obviously too when left unmolested we will have potential fly shots and again, would we rather have a point slotted the rare times we get lucky and hit that?

Also in this weird scenario we own the cube which will allow us to cash the game when our opponent is forced to make big plays like hitting loose. We probably cash 1/6th of the games immediately when our opponent rolls poorly if we make the right play. With the slot the four point nonsense not so much.

Stick

On 11/15/2022 5:32 PM, Stick Rice wrote:
> Of course the second two twos are 4(2)....other than the as mentioned potential lessening of crunching, you will get shots immediately sometimes. Offhand I'm sure there's a big swing if the opponent rolls [65 61] and one was silly enough to slot the four point. Obviously too when left unmolested we will have potential fly shots and again, would we rather have a point slotted the rare times we get lucky and hit that?
>
> Also in this weird scenario we own the cube which will allow us to cash the game when our opponent is forced to make big plays like hitting loose. We probably cash 1/6th of the games immediately when our opponent rolls poorly if we make the right play. With the slot the four point nonsense not so much.

But the main alternative isn't 8/4; it's 8/6(2). I don't see how
your comments address that.

---
Tim Chow