The other day I enjoyed hitting a first checker in a 'coup classique' position. Though I succeeded in eventually closing out both checkers and winning after a recipe, there were a lot of plays where I wasn't sure what I should be trying to do, so I thought it would be worthwhile spending some time playing it out repeatedly as a 'Deliberate Practice' exercise.
Right away, though, as I started cycling through the 21 dice rolls for the opening position, I found the evaluation depth for some of the likely plays were so low that the results were way off. With an initial 23 for example, it buries 13/8 way down in 10th place, while if you roll out both plays you get 13/8 beating out 8/5 6/4 by .013.
Okay . . so I get that XG tends to be unreliable in back game / lopsided containment positions. But then, when I tried "Play from Position" in Coaching Mode with "Champion" as my opponent, XG promptly affirms that 13/8 is the right play (see second position below) -- via a '+' level evaluation. (Though I'm still thinking just making the 8-pt should be right by a larger margin?). It also quickly picks 13/8 if I use "++ Roller" as opponent.
So, my question is
a) If I want to go through all 21 rolls in this position, what's the most efficient and reliable way for me to go about it?
and
b) If I practice playing out this position on, say 'Champion' level, can I be confident I'm getting good guidance from XG in 'Coaching' mode?
Any help appreciated.
Evaluating a 23 in "++" mode:
![](../Images/n_high.gif)
![](../Images/o_w_13.gif) ![](../Images/p_ud_b_1.gif) ![](../Images/p_up_w_1.gif) ![](../Images/p_ud_b_1.gif) ![](../Images/p_up_0.gif) ![](../Images/p_ud_b_2.gif) ![](../Images/p_up_b_1.gif) ![](../Images/b_up_0.gif) ![](../Images/p_ud_0.gif) ![](../Images/p_up_0.gif) ![](../Images/p_ud_0.gif) ![](../Images/p_up_0.gif) ![](../Images/p_ud_0.gif) ![](../Images/p_up_b_2.gif) ![](../Images/c_up_0.gif)
![](../Images/b_center23right.gif) ![](../Images/c_blank.gif)
![](../Images/o_b_0.gif) ![](../Images/p_dn_0.gif) ![](../Images/p_dd_w_1.gif) ![](../Images/p_dn_0.gif) ![](../Images/p_dd_b_2.gif) ![](../Images/p_dn_b_2.gif) ![](../Images/p_dd_b_3.gif) ![](../Images/b_dn_0.gif) ![](../Images/p_dn_0.gif) ![](../Images/p_dd_b_1.gif) ![](../Images/p_dn_0.gif) ![](../Images/p_dd_0.gif) ![](../Images/p_dn_0.gif) ![](../Images/p_dd_0.gif) ![](../Images/c_dn_2.gif)
![](../Images/n_low.gif) | | White is Player 2
score: 0 pip: 25 | Unlimited Game Jacoby Beaver | pip: 175 score: 0
Blue is Player 1 | |
XGID=--a-BBC-A----B-----AB-AaA-:1:1:1:32:0:0:3:0:10 |
Blue to play 32 |
1. | XG Roller++ | 8/5 6/4 | eq: -0.243 |
| Player: Opponent: | 47.48% (G:0.00% B:0.00%) 52.52% (G:23.00% B:13.01%) | |
|
2. | XG Roller++ | 19/16 8/6 | eq: -0.276 (-0.033) |
| Player: Opponent: | 46.71% (G:0.00% B:0.00%) 53.29% (G:24.08% B:13.42%) | |
|
3. | XG Roller++ | 20/17 8/6 | eq: -0.290 (-0.047) |
| Player: Opponent: | 46.15% (G:0.00% B:0.00%) 53.85% (G:24.40% B:13.21%) | |
|
4. | XG Roller++ | 22/20 8/5 | eq: -0.329 (-0.086) |
| Player: Opponent: | 45.32% (G:0.00% B:0.00%) 54.68% (G:25.16% B:14.35%) | |
|
5. | 4-ply | 19/17 8/5 | eq: -0.399 (-0.156) |
| Player: Opponent: | 43.07% (G:0.00% B:0.00%) 56.93% (G:25.19% B:16.02%) | |
|
6. | 4-ply | 22/19 8/6 | eq: -0.466 (-0.223) |
| Player: Opponent: | 42.51% (G:0.00% B:0.00%) 57.49% (G:28.40% B:18.25%) | |
|
7. | 3-ply | 20/18 8/5 | eq: -0.400 (-0.157) |
| Player: Opponent: | 42.67% (G:0.00% B:0.00%) 57.33% (G:24.62% B:15.72%) | |
|
8. | 2-ply | 20/17 19/17 | eq: -0.598 (-0.355) |
| Player: Opponent: | 37.27% (G:0.00% B:0.00%) 62.73% (G:29.52% B:17.99%) | |
|
9. | 2-ply | 13/10 8/6 | eq: -0.601 (-0.358) |
| Player: Opponent: | 39.32% (G:0.00% B:0.00%) 60.68% (G:29.87% B:22.73%) | |
|
10. | 2-ply | 13/8 | eq: -0.622 (-0.379) |
| Player: Opponent: | 38.07% (G:0.00% B:0.00%) 61.93% (G:29.61% B:22.13%) | |
|
eXtreme Gammon Version: 2.10
Playing from Position on "Champion" level opponent:
![](../Images/n_high.gif)
![](../Images/o_w_13.gif) ![](../Images/p_ud_b_1.gif) ![](../Images/p_up_w_1.gif) ![](../Images/p_ud_b_1.gif) ![](../Images/p_up_0.gif) ![](../Images/p_ud_b_2.gif) ![](../Images/p_up_b_1.gif) ![](../Images/b_up_0.gif) ![](../Images/p_ud_0.gif) ![](../Images/p_up_0.gif) ![](../Images/p_ud_0.gif) ![](../Images/p_up_0.gif) ![](../Images/p_ud_0.gif) ![](../Images/p_up_b_2.gif) ![](../Images/c_up_0.gif)
![](../Images/b_center23right.gif) ![](../Images/c_blank.gif)
![](../Images/o_b_0.gif) ![](../Images/p_dn_0.gif) ![](../Images/p_dd_w_1.gif) ![](../Images/p_dn_0.gif) ![](../Images/p_dd_b_2.gif) ![](../Images/p_dn_b_2.gif) ![](../Images/p_dd_b_3.gif) ![](../Images/b_dn_0.gif) ![](../Images/p_dn_0.gif) ![](../Images/p_dd_b_1.gif) ![](../Images/p_dn_0.gif) ![](../Images/p_dd_0.gif) ![](../Images/p_dn_0.gif) ![](../Images/p_dd_0.gif) ![](../Images/c_dn_2.gif)
![](../Images/n_low.gif) | | White is Champion
score: 0 pip: 25 | Unlimited Game Jacoby Beaver | pip: 175 score: 0
Blue is Player 1 | |
XGID=--a-BBC-A----B-----AB-AaA-:1:1:1:32:0:0:3:0:10 |
Blue to play 32 |
1. | XG Roller++ | 20/17 8/6 | eq: -0.290 |
| Player: Opponent: | 46.15% (G:0.00% B:0.00%) 53.85% (G:24.40% B:13.21%) | |
|
2. | XG Roller++ | 22/20 8/5 | eq: -0.329 (-0.039) |
| Player: Opponent: | 45.32% (G:0.00% B:0.00%) 54.68% (G:25.16% B:14.35%) | |
|
3. | XG Roller+ | 13/8 | eq: -0.188 (+0.102) |
| Player: Opponent: | 49.30% (G:0.00% B:0.00%) 50.70% (G:21.29% B:13.47%) | |
|
4. | XG Roller+ | 8/5 6/4 | eq: -0.205 (+0.086) |
| Player: Opponent: | 48.96% (G:0.00% B:0.00%) 51.04% (G:23.47% B:12.17%) | |
|
5. | XG Roller+ | 19/16 8/6 | eq: -0.224 (+0.066) |
| Player: Opponent: | 48.63% (G:0.00% B:0.00%) 51.37% (G:23.54% B:13.25%) | |
|
eXtreme Gammon Version: 2.10