Stay Or Go – Problem 2 4/10/16

Unlimited (Money Game)

One of the decisions we often face is deciding when to run the back checker. Here is a little problem taken from an article by Mary Hickey that requires you to make a stay or go decision.


Problem of the Week 1 – Solution

The best play is 7/6 7/4, although the other plays that clear the 7 point are only fractionally worse (see rollout results at the end). Comments suggested clearing the 8point, and in many cases clearing from the back of the prime is correct. Against the 2 point anchor however things are a bit different. Why not clear from the back? Playing fives is the key. Once the outfield checker is home 5s become a big issue if you clear the 7 point. They can’t be played from the 8, so a few 5s and you are likely to end up being forced to move off the 6 point with 5s while still having checkers on the 8 point.

One of the ways to think about a bear in against an anchor is to look for your problem numbers and try to make them play as well as possible. Against a deep anchor these are often going to be large numbers that force you to play behind the anchor, so it is often right to look at how 6s play, then how 5s play and so on.  Sixes don’t play if you clear the 7 point in this situation (once the outfield checker comes around) so they are not going to create the same issues as 5s.
1. Rollout¹ 7/6 7/4 eq:+1.059
Player: 80.01% (G:52.66% B:2.68%)
Opponent: 19.99% (G:0.65% B:0.02%)
Confidence: ±0.003 (+1.056..+1.062) – [98.0%]
Duration: 2 minutes 23 seconds

2. Rollout¹ 7/5(2) eq:+1.055 (-0.005)
Player: 79.87% (G:52.51% B:2.70%)
Opponent: 20.13% (G:0.71% B:0.02%)
Confidence: ±0.003 (+1.051..+1.058) – [1.8%]
Duration: 2 minutes 05 seconds

3. Rollout¹ 14/13 7/6 7/5 eq:+1.053 (-0.007)
Player: 79.92% (G:52.32% B:2.62%)
Opponent: 20.08% (G:0.68% B:0.02%)
Confidence: ±0.003 (+1.050..+1.056) – [0.2%]
Duration: 2 minutes 11 seconds

4. Rollout¹ 8/6(2) eq:+1.023 (-0.036)
Player: 78.65% (G:52.69% B:2.38%)
Opponent: 21.35% (G:0.75% B:0.03%)
Confidence: ±0.003 (+1.020..+1.026) – [0.0%]
Duration: 2 minutes 01 second

5. Rollout¹ 8/7 8/5 eq:+1.010 (-0.049)
Player: 78.48% (G:51.94% B:2.23%)
Opponent: 21.52% (G:0.81% B:0.03%)
Confidence: ±0.003 (+1.007..+1.014) – [0.0%]
Duration: 1 minute 34 seconds
¹ 10368 Games rolled with Variance Reduction.
Moves: 2-ply, cube decisions: 3-ply Red

Problem of the Week — 10/25/15

Unlimited (Money) Game. Black to play 11

Welcome to the Problem of the Week

We are starting a new feature on the Milwaukee Backgammon Club website, the Problem of the Week. Each week we will post a problem and ask our members and other interested backgammon players to discuss the position and explain what they believe the best move is, and why. The following week we will post a rollout of the position — and hopefully be able to provide an explanation of the reasoning why the best move is the best. Don’t be shy, join the discussion and share in the learning.