Two Plus Two Forums
Sports and Games
Chess and Other Board Games
Backgammon Forum hosted by Bill Robertie.
Problem of the Week #29: Solution
09-27-2009
, 03:41 PM
Problem of the Week #29: Solution
Cash game. Center cube. Black on move.
Black to play 6-4.
This is a comparatively easy problem if you can properly balance the key features of the position. Let’s step back for a second and look at just what is happening, before we try to evaluate the different choices.
The race: Black will trail in the race by 16 pips after he plays his 6-4. Considering that he has five men back to White’s two, he’s not as far behind as one might think at first glance. Since he’s trailing in the race, however, he wants to maintain a good anchor (to generate some shots) and a good blockade (to contain blots he may hit).
Blockades: Black has four good points in front of White’s anchor. That’s a solid plus for him, if he can maintain it. White has a motley collection of scattered points, which indicates that he probably won’t be able to build a good block anytime soon, and that he’ll likely have to start leaving shots in the near future.
Weaknesses: For Black, what might seem a strength is actually a long-term weakness. He has two great anchors, on the 20-point and the 18-point, but that’s one great anchor too many. The 20-point/18-point combination doesn’t work well together; they tie up 76 pips at a time when maneuvering freely is still key.
White’s weakness is glaringly obvious; it’s the 2-point, too deep in his board to be useful at this stage. White might have had good reason to make it in the past, but now he’d be better off if those checkers were back on the 4-point or the 9-point.
Now let’s put all this together and see just what we can do with the 6-4.
8/2 6/2. A bad choice. Black burns two of his remaining builders to make a useless point far behind White’s anchor. Now all his remaining points are stripped and his only convenient rolls next turn are those that can be made entirely with the blot on the 24-point. Take a look at how numbers like 4-1, 3-2, 6-1, 5-2, 4-3, 5-1, and 6-4 play next turn. In complex middle games with action on both sides of the board you need checkers that can move easily, and sometimes you have to take risks to preserve those checkers.
24/18 6/2 and 24/20 8/2. Not as committal as making the 2-point, but half-hearted versions of the same idea. You only have 15 checkers, and you want everyone in play at this stage of the game.
20/10. To those who worship the 5-point, this looks like a shocking idea. Black breaks the defensive 5-point before he must. But it’s really a fine move, which solves all Black’s problems at once. Black doesn’t need both anchors, so he gives one up voluntarily. If he had a choice, he’d rather give up the 18-point, because the 20-point is objectively better than the 18. But he doesn’t have that choice, so he takes what the dice give.
Take a look at the position after 20/10 and notice how Black has solved most of his problems. He now has five spare checkers, ensuring that he won’t have to concede any valuable points in the near future. He’s got more combinations to make his 5-point or 7-point, as well as more ways to attack if White should split his back checkers for some reason. Finally, he’s resolved the issue of too many anchors in a neat and efficient fashion.
If you missed this problem, it’s probably because you’re too focused on static features of the position, and not enough on the flow of the game. Try to anticipate how the game is likely to develop over the next couple of rolls, and avoid positions where you have a real shortage of checkers that can move.
Solution: 20/10.
Cash game. Center cube. Black on move.
Black to play 6-4.
This is a comparatively easy problem if you can properly balance the key features of the position. Let’s step back for a second and look at just what is happening, before we try to evaluate the different choices.
The race: Black will trail in the race by 16 pips after he plays his 6-4. Considering that he has five men back to White’s two, he’s not as far behind as one might think at first glance. Since he’s trailing in the race, however, he wants to maintain a good anchor (to generate some shots) and a good blockade (to contain blots he may hit).
Blockades: Black has four good points in front of White’s anchor. That’s a solid plus for him, if he can maintain it. White has a motley collection of scattered points, which indicates that he probably won’t be able to build a good block anytime soon, and that he’ll likely have to start leaving shots in the near future.
Weaknesses: For Black, what might seem a strength is actually a long-term weakness. He has two great anchors, on the 20-point and the 18-point, but that’s one great anchor too many. The 20-point/18-point combination doesn’t work well together; they tie up 76 pips at a time when maneuvering freely is still key.
White’s weakness is glaringly obvious; it’s the 2-point, too deep in his board to be useful at this stage. White might have had good reason to make it in the past, but now he’d be better off if those checkers were back on the 4-point or the 9-point.
Now let’s put all this together and see just what we can do with the 6-4.
8/2 6/2. A bad choice. Black burns two of his remaining builders to make a useless point far behind White’s anchor. Now all his remaining points are stripped and his only convenient rolls next turn are those that can be made entirely with the blot on the 24-point. Take a look at how numbers like 4-1, 3-2, 6-1, 5-2, 4-3, 5-1, and 6-4 play next turn. In complex middle games with action on both sides of the board you need checkers that can move easily, and sometimes you have to take risks to preserve those checkers.
24/18 6/2 and 24/20 8/2. Not as committal as making the 2-point, but half-hearted versions of the same idea. You only have 15 checkers, and you want everyone in play at this stage of the game.
20/10. To those who worship the 5-point, this looks like a shocking idea. Black breaks the defensive 5-point before he must. But it’s really a fine move, which solves all Black’s problems at once. Black doesn’t need both anchors, so he gives one up voluntarily. If he had a choice, he’d rather give up the 18-point, because the 20-point is objectively better than the 18. But he doesn’t have that choice, so he takes what the dice give.
Take a look at the position after 20/10 and notice how Black has solved most of his problems. He now has five spare checkers, ensuring that he won’t have to concede any valuable points in the near future. He’s got more combinations to make his 5-point or 7-point, as well as more ways to attack if White should split his back checkers for some reason. Finally, he’s resolved the issue of too many anchors in a neat and efficient fashion.
If you missed this problem, it’s probably because you’re too focused on static features of the position, and not enough on the flow of the game. Try to anticipate how the game is likely to develop over the next couple of rolls, and avoid positions where you have a real shortage of checkers that can move.
Solution: 20/10.
