XGID=-a---bE-C---cE----Bebb----:0:0:1:44:0:0:0:0:10

X:Player 1 O:Player 2
Score is X:0 O:0. Unlimited Game
+13-14-15-16-17-18------19-20-21-22-23-24-+
| X X | | O O O |
| X X | | O O O |
| X | | O |
| X | | O |
| X | | O |
| |BAR| |
| | | X |
| | | X |
| O X | | X |
| O X | | X O |
| O X | | X O O |
+12-11-10--9--8--7-------6--5--4--3--2--1-+
Pip count X: 155 O: 151 X-O: 0-0
Cube: 1
X to play 44

---
Tim Chow

--- SoupGate-Win32 v1.05
* Origin: fsxNet Usenet Gateway (21:1/5)

On 8/23/2022 8:35 AM, Timothy Chow wrote:

XGID=-a---bE-C---cE----Bebb----:0:0:1:44:0:0:0:0:10

X:Player 1   O:Player 2
Score is X:0 O:0. Unlimited Game
 +13-14-15-16-17-18------19-20-21-22-23-24-+
 | X              X |   | O  O  O          |
 | X              X |   | O  O  O          |
 | X                |   | O                |
 | X                |   | O                |
 | X                |   | O                |
 |                  |BAR|                  |
 |                  |   | X                |
 |                  |   | X                |
 | O           X    |   | X                |
 | O           X    |   | X  O             |
 | O           X    |   | X  O           O |
 +12-11-10--9--8--7-------6--5--4--3--2--1-+
Pip count  X: 155  O: 151 X-O: 0-0
Cube: 1
X to play 44

X will have a pretty good lead in the race after this play, so the game
plan should be to race. That iUnstacking the midpointmplies 18/14(2).
Then, it's a choice between continuing on to the ten point or bringing
two down to make the nine point. Nine point looks more flexible so I'll
do that. Unstacking the midpoint can't be too bad an idea.

18/14(2) 13/9(2).


--
Ah....Clem
The future is fun, the future is fair.

--- SoupGate-Win32 v1.05
* Origin: fsxNet Usenet Gateway (21:1/5)

Timothy Chow wrote:

XGID=-a---bE-C---cE----Bebb----:0:0:1:44:0:0:0:0:10

X:Player 1 O:Player 2
Score is X:0 O:0. Unlimited Game
+13-14-15-16-17-18------19-20-21-22-23-24-+
| X X | | O O O |
| X X | | O O O |
| X | | O |
| X | | O |
| X | | O |
| |BAR| |
| | | X |
| | | X |
| O X | | X |
| O X | | X O |
| O X | | X O O | +12-11-10--9--8--7-------6--5--4--3--2--1-+
Pip count X: 155 O: 151 X-O: 0-0
Cube: 1
X to play 44

---
Tim Chow

I find it difficult to run from the 18-point so this is a good
opportunity to do so safely. Might as well set another anchor on my
outer board too.

18/14(2), 13/9(2)

--- SoupGate-Win32 v1.05
* Origin: fsxNet Usenet Gateway (21:1/5)

XGID=-a---bE-C---cE----Bebb----:0:0:1:44:0:0:0:0:10

X:Player 1 O:Player 2
Score is X:0 O:0. Unlimited Game
+13-14-15-16-17-18------19-20-21-22-23-24-+
| X X | | O O O |
| X X | | O O O |
| X | | O |
| X | | O |
| X | | O |
| |BAR| |
| | | X |
| | | X |
| O X | | X |
| O X | | X O |
| O X | | X O O |
+12-11-10--9--8--7-------6--5--4--3--2--1-+
Pip count X: 155 O: 151 X-O: 0-0
Cube: 1
X to play 44

My first instinct here was 18/14(2) 13/9(2), but then I talked myself
into 18/10(2), reasoning that X is just trying to come home safely,
and two stripped outfield points are harder to clear than one.

In the variant below, I have move O's "guard" on her 24pt up to her
20pt, and in that case, XG favors 18/10(2). In this variant, X can
freely dump behind O's anchor. But in the given position, he doesn't
have the same freedom. Among other things, having extra points in the
outfield gives X better defensive chances if he is hit.

I did rollouts with GNU Backgammon to see if the percentage of time
that X gets hit is larger after 18/14(2) 13/9(2) than after 18/10(2). Apparently, the answer is no; X gets hit about 60-65% of the time after
either play. But *if* X gets hit, his survival chances are better if
he has more points made.

1. Rollout¹ 18/14(2) 13/9(2) eq:+0.198
Player: 56.78% (G:5.51% B:0.24%)
Opponent: 43.22% (G:10.18% B:0.20%)
Confidence: ±0.012 (+0.186..+0.211) - [100.0%]

2. Rollout¹ 18/10(2) eq:+0.119 (-0.079)
Player: 54.61% (G:5.41% B:0.20%)
Opponent: 45.39% (G:11.66% B:0.18%)
Confidence: ±0.012 (+0.107..+0.131) - [0.0%]

3. Rollout¹ 13/9(2) 6/2(2) eq:+0.096 (-0.103)
Player: 53.61% (G:8.76% B:0.33%)
Opponent: 46.39% (G:12.47% B:0.31%)
Confidence: ±0.016 (+0.080..+0.112) - [0.0%]

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

eXtreme Gammon Version: 2.19.207.pre-release

-------
Variant
-------

XGID=-----cE-C---cE----Bebb----:0:0:1:44:0:0:0:0:10

X:Player 1 O:Player 2
Score is X:0 O:0. Unlimited Game
+13-14-15-16-17-18------19-20-21-22-23-24-+
| X X | | O O O |
| X X | | O O O |
| X | | O |
| X | | O |
| X | | O |
| |BAR| |
| | | X |
| | | X |
| O X | | X O |
| O X | | X O |
| O X | | X O |
+12-11-10--9--8--7-------6--5--4--3--2--1-+
Pip count X: 155 O: 147 X-O: 0-0
Cube: 1
X to play 44

1. Rollout¹ 18/10(2) eq:+0.272
Player: 58.04% (G:1.62% B:0.05%)
Opponent: 41.96% (G:1.94% B:0.04%)
Confidence: ±0.010 (+0.262..+0.281) - [100.0%]

2. Rollout¹ 18/14(2) 13/9(2) eq:+0.243 (-0.029)
Player: 56.98% (G:1.83% B:0.05%)
Opponent: 43.02% (G:2.44% B:0.04%)
Confidence: ±0.010 (+0.233..+0.253) - [0.0%]

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

eXtreme Gammon Version: 2.19.207.pre-release

---
Tim Chow

--- SoupGate-Win32 v1.05
* Origin: fsxNet Usenet Gateway (21:1/5)

XGID=-aB---D-EA--aBa-bcbcb-A---:1:1:1:44:0:0:0:0:10

Score is X:0 O:0. Unlimited Game
+13-14-15-16-17-18------19-20-21-22-23-24-+
| X O O O O | | O O X |
| X O O O | | O O |
| O | | O |
| | | |
| | | |
| |BAR| |
| X | | |
| X | | X |
| X | | X | +---+
| X | | X X | | 2 |
| O X X | | X X O | +---+
+12-11-10--9--8--7-------6--5--4--3--2--1-+
Pip count X: 125 O: 132 X-O: 0-0
Cube: 2, X own cube
X to play 44

---
Tim Chow

--- SoupGate-Win32 v1.05
* Origin: fsxNet Usenet Gateway (21:1/5)

XGID=-aB---D-EA--aBa-bcbcb-A---:1:1:1:44:0:0:0:0:10

Score is X:0 O:0. Unlimited Game
+13-14-15-16-17-18------19-20-21-22-23-24-+
| X O O O O | | O O X |
| X O O O | | O O |
| O | | O |
| | | |
| | | |
| |BAR| |
| X | | |
| X | | X |
| X | | X | +---+
| X | | X X | | 2 |
| O X X | | X X O | +---+
+12-11-10--9--8--7-------6--5--4--3--2--1-+
Pip count X: 125 O: 132 X-O: 0-0
Cube: 2, X own cube
X to play 44

Being significant ahead in the pip count, I didn't want to risk getting
another checker sent behind O's five-prime, so I played 13/9(2) 8/4(2).
But X is the clear underdog here, and attacking is his best chance to
turn the game around. He has plenty of checkers in the zone, and has
a stronger board than O does. Plus, O has other blots that could get
picked up. What if O didn't have those outfield blots? See the
variant below.

1. Rollout¹ 9/1* 8/4(2) eq:-0.373
Player: 28.94% (G:9.59% B:0.18%)
Opponent: 71.06% (G:13.71% B:0.69%)
Confidence: ±0.008 (-0.381..-0.365) - [100.0%]

2. Rollout¹ 9/5 8/4(3) eq:-0.484 (-0.112)
Player: 26.26% (G:8.82% B:0.30%)
Opponent: 73.74% (G:17.34% B:0.86%)
Confidence: ±0.009 (-0.494..-0.475) - [0.0%]

3. Rollout¹ 13/9(2) 8/4(2) eq:-0.485 (-0.112)
Player: 24.36% (G:6.29% B:0.17%)
Opponent: 75.64% (G:10.97% B:0.41%)
Confidence: ±0.008 (-0.493..-0.477) - [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

-------
Variant
-------

XGID=-aB---D-EA---Bb-bcbcb-A---:1:1:1:44:0:0:0:0:10

Score is X:0 O:0. Unlimited Game
+13-14-15-16-17-18------19-20-21-22-23-24-+
| X O O O O | | O O X |
| X O O O O | | O O |
| O | | O |
| | | |
| | | |
| |BAR| |
| X | | |
| X | | X |
| X | | X | +---+
| X | | X X | | 2 |
| X X | | X X O | +---+
+12-11-10--9--8--7-------6--5--4--3--2--1-+
Pip count X: 125 O: 130 X-O: 0-0
Cube: 2, X own cube
X to play 44

1. Rollout¹ 9/1* 8/4(2) eq:-0.400
Player: 28.66% (G:7.50% B:0.11%)
Opponent: 71.34% (G:13.58% B:0.63%)
Confidence: ±0.008 (-0.408..-0.392) - [99.4%]

2. Rollout¹ 13/9 8/4(3) eq:-0.414 (-0.014)
Player: 27.80% (G:7.34% B:0.16%)
Opponent: 72.20% (G:13.00% B:0.51%)
Confidence: ±0.007 (-0.422..-0.407) - [0.6%]

3. Rollout¹ 13/9(2) 8/4(2) eq:-0.451 (-0.051)
Player: 25.86% (G:6.32% B:0.15%)
Opponent: 74.14% (G:10.94% B:0.37%)
Confidence: ±0.007 (-0.458..-0.444) - [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

--- SoupGate-Win32 v1.05
* Origin: fsxNet Usenet Gateway (21:1/5)