Question:
Red to play 5-2
Option 1: bar/23-7/2
votes: 0
Option 2: bar/18
votes: 2
Option 3: bar/23-13/8
votes: 8
Option 4: bar/23-6/1
votes: 0
Option 5: none
votes: 0
Position information:
Pip-count: Red 132-73 White
Score: Red 5-4 White
Match: 7-pointer
(http://www.freewebs.com/persianlord/position30.png)
First make your choice and then read on.
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Spoiler
Red is in a very perilous position. With the cube on 2 and match to 7, he should really fear a gammon loss which will finish him off. So his #1 periority should be avoiding a gammon loss, not wishing desperately to get a late shot by staying. Thus he should simply and wisely, not cowardly, escape with bar/18 in hope of not getting hit next round and starting a hard, but possible gammon-saving project. Note that if he stays on the 2-pt, white will not hesitate to even hit loose, considering the red's weak home board and the great value of a gammon win, and this is apart from the fact that with 9 rolls white will be able to close out his board (2-2,4-2, 6-2, 3-3, 6-4, 6-6). Here is GNUBG's analysis:
1. Cubeful 2-ply bar/18 Eq.: -1.242
3.6% 0.2% 0.0% - 96.4% 34.6% 0.1%
2. Cubeful 2-ply bar/23 13/8 Eq.: -1.295 ( -0.053)
8.3% 0.9% 0.0% - 91.7% 50.8% 0.2%
3. Cubeful 2-ply bar/23 7/2 Eq.: -1.333 ( -0.090)
8.5% 1.1% 0.0% - 91.5% 55.2% 0.2%
4. Cubeful 2-ply bar/23 6/1 Eq.: -1.399 ( -0.157)
7.4% 0.9% 0.0% - 92.6% 60.1% 0.2%
Note that with bar/23-13/8, your chances of a win is 8.3% versus 3.6% if you play the best move (bar/18) but the key point is in the probability of the terrific gammon loss: 50.8% versus 34.6%.
But what about if this position occurs in a DMP game (or 1-pt match)?
Had this position been taken from a DMP game, it would have been a silly blunder to escape because it will nearly guarantee a loss which is not important whether be a single, a gammon or even a backgammon:
1. Cubeful 2-ply bar/23 13/8 Eq.: -0.847
7.6% 0.5% 0.0% - 92.4% 39.6% 0.2%
2. Cubeful 2-ply bar/23 7/2 Eq.: -0.852 ( -0.005)
7.4% 0.4% 0.0% - 92.6% 44.7% 0.2%
3. Cubeful 2-ply bar/23 6/1 Eq.: -0.865 ( -0.017)
6.8% 0.4% 0.0% - 93.2% 49.4% 0.2%
4. Cubeful 2-ply bar/18 Eq.: -0.962 ( -0.115)
1.9% 0.2% 0.0% - 98.1% 18.3% 0.0%
Spoiler
Yaaay I got it right! I had to think quite a bit tho' and was probably prompted into recognising that it's an unusual sort of move for backgammon, generally a game which should be played aggressively, in which it's correct to be wimpish purely by Ali's selection of it as a problem.