FIBS Board backgammon forum
Backgammon => Fibsboard Forum Matches => FFM 15 => Topic started by: diane on June 04, 2013, 09:15:11 PM
Herd rolled 6-3 and moved the 3..
9/4, 9/5.
This will be an interesting roll out when this game is done...watch out for it.
diane asked for a rollout so here it is, courtesy of XGR++
Spoiler
Nobody asked for my opinion, but here it is anyway:
"Clear from the rear" is the aphorism we've always heard when bearing in against contact. By clearing the rearmost point you don't leave any gaps that may come back to haunt you later, and "a point that's cleared is not to be feared" , meaning once you clear the point you can't possibly blot there.
But like most rules of thumb, it is not always applicable. This is a good example. At this score gammons are particularly valuable (jumping from 32% to 49% to win the match). By giving the herd the chance to leap out with a six, the gammon chances go way down, by roughly 50%. Meanwhile, the herd's board is particularly weak with an exposed blot, so playing to pick up another checker should be on the radar. (full disclosure - it wasn't on mine, I would've kept the prime and made the ace point) Thus, the various "bot moves" at the top of the list.
I'll start a full rollout to see if this stands up....
XGID=-IB-A-----------bbbccbCa--:0:0:-1:54:4:1:1:5:3
X:Herd O:Linus
Score is X:4 O:1 5 pt.(s) match.
+12-11-10--9--8--7-------6--5--4--3--2--1-+
| O O O | | O O O X O |
| O O O | | O O O X |
| | | O O X |
| | | |
| | | |
| |BAR| |
| | | 9 |
| | | X |
| | | X |
| | | X X |
| | | X X X |
+13-14-15-16-17-18------19-20-21-22-23-24-+
Pip count X: 83 O: 91 X-O: 4-1/5 Crawford
Cube: 1
O to play 54
1. XG Roller++ 8/4 7/2 eq:+1.028
Player: 88.47% (G:25.16% B:0.77%)
Opponent: 11.53% (G:0.36% B:0.00%)
2. XG Roller++ 7/2 5/1 eq:+1.022 (-0.006)
Player: 89.71% (G:22.23% B:0.53%)
Opponent: 10.29% (G:0.26% B:0.00%)
3. XG Roller++ 8/4 6/1 eq:+1.003 (-0.025)
Player: 88.86% (G:22.00% B:0.53%)
Opponent: 11.14% (G:0.37% B:0.00%)
4. XG Roller++ 6/1 5/1 eq:+0.996 (-0.032)
Player: 89.91% (G:19.28% B:0.33%)
Opponent: 10.09% (G:0.21% B:0.00%)
5. XG Roller++ 7/2 6/2 eq:+0.992 (-0.036)
Player: 88.94% (G:20.76% B:0.58%)
Opponent: 11.06% (G:0.25% B:0.00%)
6. XG Roller++ 9/5 7/2 eq:+0.985 (-0.043)
Player: 87.67% (G:22.51% B:0.67%)
Opponent: 12.33% (G:0.40% B:0.00%)
7. XG Roller++ 9/4 5/1 eq:+0.982 (-0.045)
Player: 88.13% (G:21.41% B:0.53%)
Opponent: 11.87% (G:0.30% B:0.00%)
8. XG Roller++ 9/4 6/2 eq:+0.978 (-0.050)
Player: 88.12% (G:21.02% B:0.52%)
Opponent: 11.88% (G:0.29% B:0.00%)
9. XG Roller++ 9/5 6/1 eq:+0.973 (-0.055)
Player: 88.13% (G:20.49% B:0.49%)
Opponent: 11.87% (G:0.40% B:0.00%)
10. XG Roller++ 9/4 8/4 eq:+0.958 (-0.070)
Player: 86.21% (G:22.78% B:0.75%)
Opponent: 13.79% (G:0.72% B:0.00%)
11. XG Roller++ 6/2 6/1 eq:+0.958 (-0.070)
Player: 87.19% (G:20.87% B:0.53%)
Opponent: 12.81% (G:0.62% B:0.00%)
12. XG Roller++ 9/5 9/4 eq:+0.888 (-0.140)
Player: 88.59% (G:11.16% B:0.17%)
Opponent: 11.41% (G:0.06% B:0.00%)
eXtreme Gammon Version: 2.10, MET: Kazaross XG2
full rollout
Spoiler
the numbers change a bit, but the ordering of the plays does not. the bot move where O exposes two checkers on the 8 and 7 thereby forcing a shot with any 4 or 5 is best.
XGID=-IB-A-----------bbbccbCa--:0:0:-1:54:4:1:1:5:3
X:Herd O:Linus
Score is X:4 O:1 5 pt.(s) match.
+12-11-10--9--8--7-------6--5--4--3--2--1-+
| O O O | | O O O X O |
| O O O | | O O O X |
| | | O O X |
| | | |
| | | |
| |BAR| |
| | | 9 |
| | | X |
| | | X |
| | | X X |
| | | X X X |
+13-14-15-16-17-18------19-20-21-22-23-24-+
Pip count X: 83 O: 91 X-O: 4-1/5 Crawford
Cube: 1
O to play 54
1. Rollout¹ 8/4 7/2 eq:+1.044
Player: 88.71% (G:26.28% B:1.06%)
Opponent: 11.29% (G:0.77% B:0.00%)
Confidence: ±0.004 (+1.040..+1.049) - [100.0%]
Duration: 3 minutes 14 seconds
2. Rollout¹ 7/2 5/1 eq:+1.033 (-0.012)
Player: 89.66% (G:23.27% B:0.85%)
Opponent: 10.34% (G:0.56% B:0.01%)
Confidence: ±0.004 (+1.029..+1.036) - [0.0%]
Duration: 2 minutes 40 seconds
3. Rollout¹ 8/4 6/1 eq:+1.015 (-0.029)
Player: 89.16% (G:22.55% B:0.76%)
Opponent: 10.84% (G:0.63% B:0.02%)
Confidence: ±0.004 (+1.011..+1.019) - [0.0%]
Duration: 2 minutes 14 seconds
4. Rollout¹ 6/1 5/1 eq:+1.007 (-0.037)
Player: 90.02% (G:20.09% B:0.60%)
Opponent: 9.98% (G:0.42% B:0.00%)
Confidence: ±0.004 (+1.003..+1.011) - [0.0%]
Duration: 1 minute 28 seconds
5. Rollout¹ 7/2 6/2 eq:+1.003 (-0.041)
Player: 88.91% (G:21.89% B:0.81%)
Opponent: 11.09% (G:0.65% B:0.00%)
Confidence: ±0.004 (+0.999..+1.007) - [0.0%]
Duration: 2 minutes 09 seconds
6. Rollout¹ 9/5 9/4 eq:+0.885 (-0.159)
Player: 88.37% (G:11.73% B:0.33%)
Opponent: 11.63% (G:0.13% B:0.00%)
Confidence: ±0.003 (+0.882..+0.888) - [0.0%]
Duration: 1 minute 52 seconds
7. XG Roller++ 9/5 7/2 eq:+0.985 (-0.060)
Player: 87.67% (G:22.51% B:0.67%)
Opponent: 12.33% (G:0.40% B:0.00%)
8. XG Roller++ 9/4 5/1 eq:+0.982 (-0.062)
Player: 88.13% (G:21.41% B:0.53%)
Opponent: 11.87% (G:0.30% B:0.00%)
9. XG Roller++ 9/4 6/2 eq:+0.978 (-0.066)
Player: 88.12% (G:21.02% B:0.52%)
Opponent: 11.88% (G:0.29% B:0.00%)
10. XG Roller++ 9/5 6/1 eq:+0.973 (-0.071)
Player: 88.13% (G:20.49% B:0.49%)
Opponent: 11.87% (G:0.40% B:0.00%)
¹ 1296 Games rolled with Variance Reduction.
Moves: 3-ply, cube decisions: XG Roller
eXtreme Gammon Version: 2.10, MET: Kazaross XG2