I think the merit of 13/9 is that it is the closest to home (and for easier covering next move, for easier work (acceptance of surplus checkers) and for easier covering next move, for easier covering next move and for easier breaking up later.
          
 
       
 | | White is Player 2
score: 0
pip: 130 | | 7 point match | pip: 129
score: 4
Blue is Player 1 |
|
| XGID=---BBBBb-----EBaadbda-----:0:0:1:31:4:0:0:7:10 |
| Blue to play 31 |
| 1. | Rollout1 | 14/11 13/12 | eq: -0.061 |
| Player:
Opponent: | 50.72% (G:6.78% B:1.07%)
49.28% (G:5.57% B:0.19%) | Conf.: ± 0.006 (-0.067...-0.055) - [56.4%]
Duration: 18 minutes 26 seconds |
|
| 2. | Rollout1 | 13/9 | eq: -0.063 (-0.001) |
| Player:
Opponent: | 50.59% (G:3.12% B:0.28%)
49.41% (G:3.55% B:0.10%) | Conf.: ± 0.006 (-0.069...-0.057) - [35.4%]
Duration: 18 minutes 53 seconds |
|
| 3. | Rollout1 | 14/10 | eq: -0.066 (-0.005) |
| Player:
Opponent: | 50.47% (G:3.16% B:0.32%)
49.53% (G:3.30% B:0.07%) | Conf.: ± 0.006 (-0.072...-0.060) - [6.8%]
Duration: 16 minutes 21 seconds |
|
| 4. | Rollout1 | 13/12 13/10 | eq: -0.069 (-0.008) |
| Player:
Opponent: | 50.40% (G:3.19% B:0.29%)
49.60% (G:4.14% B:0.09%) | Conf.: ± 0.006 (-0.075...-0.063) - [1.4%]
Duration: 16 minutes 45 seconds |
|
| 5. | Rollout2 | 6/2 | eq: -0.115 (-0.053) |
| Player:
Opponent: | 49.26% (G:2.40% B:0.13%)
50.74% (G:4.12% B:0.10%) | Conf.: ± 0.010 (-0.124...-0.105) - [0.0%]
Duration: 8 minutes 59 seconds |
|
| |
1 2592 Games rolled with Variance Reduction.
Moves: 3-ply, cube decisions: XG Roller
2 1296 Games rolled with Variance Reduction.
Moves: 3-ply, cube decisions: XG Roller
|
eXtreme Gammon Version: 2.19.208.pre-release, MET: Kazaross XG2
See the next diagram with the initial 4ply XG evaluation. The 6/2 looks twice as "awful" and the 13/9 nears a blunder! (5% in my setting).
| | White is Player 2
score: 0
pip: 130 | | 7 point match | pip: 129
score: 4
Blue is Player 1 |
|
| XGID=---BBBBb-----EBaadbda-----:0:0:1:31:4:0:0:7:10 |
| Blue to play 31 |
| 1. | 4-ply | 14/11 13/12 | eq: -0.080 |
| Player:
Opponent: | 50.35% (G:2.61% B:0.08%)
49.65% (G:3.62% B:0.07%) | |
|
| 2. | 4-ply | 14/10 | eq: -0.090 (-0.009) |
| Player:
Opponent: | 50.02% (G:2.96% B:0.19%)
49.98% (G:3.40% B:0.07%) | |
|
| 3. | 4-ply | 13/12 13/10 | eq: -0.105 (-0.025) |
| Player:
Opponent: | 49.61% (G:2.64% B:0.08%)
50.39% (G:3.69% B:0.06%) | |
|
| 4. | 4-ply | 13/9 | eq: -0.117 (-0.037) |
| Player:
Opponent: | 49.21% (G:1.88% B:0.06%)
50.79% (G:3.01% B:0.05%) | |
|
| 5. | 4-ply | 6/2 | eq: -0.201 (-0.120) |
| Player:
Opponent: | 46.91% (G:1.74% B:0.06%)
53.09% (G:4.12% B:0.06%) | |
|
eXtreme Gammon Version: 2.19.208.pre-release, MET: Kazaross XG2