Problem of the Week #144: April 29


(a) Money game, center cube.




Black to play 6-1.


(b) Same position, Black to play 6-1 at double match point.


Note: All ‘cash game’ problems assume the Jacoby Rule is in effect. That is, you can’t win a gammon unless the cube has been turned.

Lets look at the moves a little:

24/17 - get a checker out and puts in a potentially strong position but leaves a good number of perms where we get ripped to bits. 2 on the bar with the cube turned against a closed board does not feel that uncommon here. On the plus side, if we do survive the blitz we are in pretty good shape, with an anchor in the outfield, a long and dangerous pass for white to get two checkers around, and a position we can go to war with.

13/7 6/5 - break the outfield point, extra possible builder/attacker for when White has to run. Looks safer but also more vague - what is the game plan here? Seem to be leaving a lot to the Gods. Our position can collapse pretty badly here a lot of the time, leaving us a poorly timed backgame and some very stuck checkers. On the plus side we probably don't get gammoned much, and are far from out of the game.

13/7 13/12 just looks like 13/7 6/5 with a few more shots so we can discount that.

Nothing else looks great.

in a) we are getting doubled after both moves and both look like takes. 24/17 we will get gammoned more, but at least we have a solid game plan if white fails to attack and close the board, and perhaps more importantly we have a potentially huge cube to ship right back at white the second their game starts to go wrong. Don't mind taking a few risks to create clarity in my mind/game plan here - in a) I think I go 24/17 but this may be a blunder as the gammons are def higher than 13/7 6/5 and the cube will be in play.

If in a) it's 24/17 in b) it surely has to be. We don't care about gammons, lets just run the checker, grab the outfield and try and force the game in our favour. Who dares wins.

a) 24/17
b) 24/17

I wont take the cube after running in part a so 13/7,6/5. Too many gammons
With no gammons run out 24/17.

a) 13/7, 6/5, take the cube when it comes, brace for ace point game and don't sweat the blot on the 13.

b) I guess 24/17 and hope for the best.

24/17 is clearly the best way to win.. and the most likely way to pay off 4. In b, we don't care about paying off extra, so it has to be right. In a, guess I'm playing safe, and 13/7 6/5 seems slightly better. Both allow the same number of hits (44 is blocked), but I'd rather he play 63/54 hitting me and 62/53 in front of me than 62/53 hitting me and 63/54 over the top of me.

a) 13/7 6/5
b) 24/17

While I am tempted to follow the theme of the last problem of the week and run a checker out, both our positions are very fragile. It doesnt look right to step out and get pointed on, when our opponents board could crack within a couple rolls, or he could be forced to run out a single checker.

a) 13/7 6/5
b)13/7 6/5

OTB I play 24/17 and pray for both of them...probably not correct for both based on QF.

In a money game, Black would be asking to be gammoned if he were to run out with this 61. White would surely attack. Awkward throws such as 41 42 43 and 44 would suddenly become hitting numbers for White. Black should bide his time.

My solution in Part (a): 13/7, 6/5

At DMP, can Black risk running? When Black runs, White’s POH rolls are 22 23 24 26 33 34 36 46. Although 55 and 66 are also POH numbers, White would likely play them by running himself. So there are 14 rolls that would make the 24pt on Black’s head. But that means there are 22 rolls that do not. And Black gets some juicy return shots whenever White hits loose. Partly due to QF (quiz factor), I will guess Black should run. Over the board, I am not sure I would be up to it.

My solution in Part (b): 24/17

For the Record
I am so often wrong that I like to post my record in these messages. It's kind of a truth-in-advertising thing. Grunch: I have been answering these problems without the use of a bot, and before checking the excellent solutions of others, since Problem 28. My record at this writing is 53%.

I have no clue. Escaping looks like a thing hard to do. But a ton of gammons. We can also crouch, waiting for White to crunch or attacking when he leaves the anchor. It depends on the wins and the gammon rates. Escaping will perhaps win the most games, but lost also the most gammons. So this is for sure the DMP play. In a chouette, i will play 13/7 6/5. It could be, winning after crouching as a sidekick, some one will be put a little be on tilt.

Robertie 144
“Do what is hardest first?” echoes in my mind. But it just can’t be right here, can it? After 24/17 white has a perfect diversification and thus will hit with any 2,3,4 and escape with any 5 or 6. And I am behind in the race, so why should I leave my anchor. Shrinking my prime is not right either, so I play 13/7 6/5. At DMP being gammoned is not hurting extra but still I would play the same

Answer: 13/7 6/5

The difference between playing 24->17 and 13->7 etc is that we have a better overall win probability in the first case that however comes with more frequent losing gammons. So if one is playing to win regardless of whatever risk of gammons (double match point) you must try 24-17.

White has a timing problem. Next roll he will run or crash the prime. If we leave the 24 spot, we will help white with low rolls. if white rolls high, he will need to run and black can hit and try to close the prime itself. If white would had another cheker around the board it would have been different, but here seems to me a big blunder to leave the anchor.

13/7 6/5

Also make a note here that is important. If the cude is to be used later (ie no winner take all situation that gammons are irrelevant and win loss only matters either way) we must immediately realize here that if we play 1-6 as 24-17 the very next move we face a double by the white and we have to probably take it which opens the door to massive losses. If we didnt play it that way maybe the white wont double us and will do so later or never.

That detail must also get into the calculations. I am almost sure next move is a double when you take one outside.

Since no one has yet taken up the role, let me be the nay sayer. In Part (a), I would probably pass a double after running out with 24/17. This seems like a position where Jacoby has been protecting Black somewhat, and my guess is that there is a big equity loss when gammons are activated.

After the more conservative 13/7 6/5, however, I think Black can take. He’s still an obvious dog, but based on White’s bad 4s, and a few tactical variations, I don’t think he should surrender.

b) Gammons don't count. White has 20 escaping numbers and 16 pointing numbers(66,55,33,22,64,63,62,43,42,32), not counting when he could hit and leave an inner blot, if Black escapes one checker. Even if it sounds dangerous, I'm trying the big escape now.

24/17

a) Gammons could be activated, so we need to be more careful. But if we don't escape now, the situation likely won't improve and White might have an efficient double later on. Still the big escape.

24/17