Players of all levels are invited to share their view on these interesting positions that we came across while honing our backgammon skills in match play.
Is the computer program always right? As we have seen in the past, even the best programs get certain scenarios wrong while world class human players have a better grasp of these situations through the experience of years of play.
The "Brain Busters" series offers three new backgammon positions in each article, problems that we believe to be challenging and worthy of thought and discussion - please post your opinion on how you would play these positions in the forum thread below.
We will do their rollouts with Snowie 4 Pro and publish the results along with a new set of positions about once a week. Enjoy!
Note: See the rollouts results of all previous Brain Busters articles at this
link.
Please give us your thoughts on these without the help of a bot.
Position 1:
|
  
         
    
          
  
|
|
| Pip: 142 |
7 point match
Green-White:
Score 0-0 |
| Pip: 145 |
| |
Position 2:
|
   
|
|
| Pip: 150 |
7 point match
Green-White:
Score 5-2 |
| Pip: 176 |
| |
Position 3: Green on roll, cube action?
|
  
|
|
| Pip: 127 |
5 point match
Green-White:
Score 0-0 |
| Pip: 122 |
| |
WARNING! - ROLLOUTS
March 21, 2006: Here are the Snowie rollouts for the three positions above:
Position 1:
|
|
|
| Pip: 142 |
7 point match
Green-White:
Score 0-0 |
| Pip: 145 |
| |
| # |
Ply | Move | Equity |
| |
1 |
R |
13/9 2/1* |
-0.276 |
| | |
0.3% 12.0% 45.7% 54.3% 22.9% 1.0% |
| | |
95% confidence interval:
- money cubeless eq.: -0.201 ±0.037.
Rollout settings:
Full rollout,
144 games (equiv. 5222 games),
played 3-ply (precise),
random seed, with race database.
|
| |
2 |
R |
9/5 6/5 |
-0.425 (-0.149) |
| | |
0.8% 13.8% 43.7% 56.3% 30.5% 1.2% |
| | |
95% confidence interval:
- money cubeless eq.: -0.296 ±0.049.
Rollout settings:
Full rollout,
144 games (equiv. 4033 games),
played 3-ply (precise),
random seed, with race database.
|
| |
3 |
R |
9/8 6/2 |
-0.535 (-0.259) |
| | |
0.4% 10.5% 41.1% 58.9% 29.2% 0.7% |
| | |
95% confidence interval:
- money cubeless eq.: -0.368 ±0.035.
Rollout settings:
Full rollout,
144 games (equiv. 5688 games),
played 3-ply (precise),
random seed, with race database.
|
| |
4 |
3 |
13/8 |
-0.429 (-0.152) |
| | |
0.6% 11.7% 42.8% 57.2% 28.7% 1.4% |
| | |
Speed Parameter: Precise.
|
| |
5 |
3 |
6/2 3/2 |
-0.525 (-0.249) |
| | |
0.4% 9.8% 40.3% 59.7% 26.1% 0.9% |
| | |
Speed Parameter: Fast.
|
Position 2:
|
|
|
| Pip: 150 |
7 point match
Green-White:
Score 5-2 |
| Pip: 176 |
| |
| # |
Ply | Move | Equity |
| |
1 |
R |
13/7(2) 11/5*(2) |
0.608 |
| | |
1.3% 29.5% 66.8% 33.2% 7.5% 0.6% |
| | |
95% confidence interval:
- money cubeless eq.: 0.563 ±0.028.
Rollout settings:
Full rollout,
288 games (equiv. 8498 games),
played 3-ply (precise),
random seed, with race database.
|
| |
2 |
R |
11/5*(2) 8/2(2) |
0.588 (-0.020) |
| | |
1.1% 32.7% 64.1% 35.9% 7.6% 0.5% |
| | |
95% confidence interval:
- money cubeless eq.: 0.539 ±0.025.
Rollout settings:
Full rollout,
288 games (equiv. 10253 games),
played 3-ply (precise),
random seed, with race database.
|
| |
3 |
R |
24/18(2) 11/5*(2) |
0.569 (-0.039) |
| | |
0.7% 24.4% 66.8% 33.2% 6.0% 0.2% |
| | |
95% confidence interval:
- money cubeless eq.: 0.525 ±0.024.
Rollout settings:
Full rollout,
288 games (equiv. 9589 games),
played 3-ply (precise),
random seed, with race database.
|
| |
4 |
R |
24/18 13/7 11/5*(2) |
0.460 (-0.148) |
| | |
0.4% 25.1% 64.7% 35.3% 7.9% 1.0% |
| | |
95% confidence interval:
- money cubeless eq.: 0.460 ±0.046.
Rollout settings:
Full rollout,
144 games (equiv. 3881 games),
played 3-ply (precise),
random seed, with race database.
|
| |
5 |
3 |
24/18 11/5*(2) 8/2 |
0.240 (-0.368) |
| | |
1.1% 23.7% 58.5% 41.5% 10.7% 0.7% |
| | |
Speed Parameter: Fast.
|
Position 3: Green on roll, cube action?
|
|
|
| Pip: 127 |
5 point match
Green-White:
Score 0-0 |
| Pip: 122 |
| |
| Cube action equity |
| Rollout |
Money equity: |
0.824 |
| |
2.3% 46.9% 71.4% 28.6% 9.2% 0.4%
|
| |
95% confidence interval:
- money cubeless eq.: 0.824 ±0.017,
- live cube no redouble: 1.077 ±0.022,
- live cube redouble take: 1.286 ±0.037.
Rollout settings:
Full rollout,
648 games (equiv. 23785 games),
played 3-ply (precise), cube 3-ply,
random seed, with race database.
|
| Evaluations |
| 1. |
No redouble |
1.058 |
|
| 2. |
Redouble, pass |
1.000 |
(-0.058) |
| 3. |
Redouble, take |
1.299 |
(+0.241) |
| Proper cube action: Too good to redouble, pass | 19% |
| Live cube |
| 1. |
No redouble |
1.077 |
|
| 2. |
Redouble, pass |
1.000 |
(-0.077) |
| 3. |
Redouble, take |
1.286 |
(+0.209) |
| Proper cube action: Too good to redouble, pass | 27% |
(19%)
