Problem of the Week #83: November 8


(a) Cash game, Black owns the cube. Black on roll.





Black to play 2-2.



(b) Cash game, Black owns the cube. Black on roll.





Black to play 2-2.


(c) Cash game, Black owns the cube. Black on roll.





Black to play 2-2.



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.

(a) I still play 8/4(2). Above all, you need white to crack his prime so you don't get stuck with a bunch of checkers on your ace point. So just don't hit anything.

(b) 13/11*/7*, 6/4, In this case, there is a crack. I think your goal is to pound white's blots and hope that you can roll enough 5s and 6s to get out while building up some blocking points to get white awkward on his side of the board. Is this asking too much? Maybe. But I see no other way of winning. It might be right to make your bar point here, and leave the blot exposed, but I think you want white to be frozen for as long as possible to give you a window to escape. (I think hitting two is an important feature. If you can only hit one, it might be better to stay with the backgame and take the time now to focus on building a board.)

(c) If I'm going to hold all three points, then I don't hit in the outfield and do something like 8/4(2). If I'm trying to play moving forward, I'll play 23/21(2) 9/7* 6/4. I think I'll take the latter. I've got an ace point game to fall back on (which will probably be well-timed), plus it decreases my chances of getting gammoned.

wow. these are very interesting and there is a good chance that I blunder hard here. I know from playing snowie that these positions can be difficult and highly dangerous. that being said....

A) Here even though hitting twice isn't ideal I play 13/11*/7* and 6/4 with the last deuce. timeing is important, of course but so is structure. There is little point of 8/4 (2), it just looks brutal in terms of structure. While 8/4 (2) avoids hitting and speeds up whites progress, we also need to consider our own timing. in this case I think 8/4 (2) hurts our timing more then double hitting improves whites.

B) I make the same play here with more certainty. 13/11*/7*. If we can escape with a five, we have a decent chance of containment.

C) In this variation I like 13/11* 9/7* and 6/4 with the first three. with the last one i like 23/21, stepping up and preparing to escape a checker.

I don't want to get hit again, and I want to get my checkers home in case I get a chance to bear one off. I'll move 13/11* (2) and and 9/7* and 6/4 to cover the checker in my home board. I don't really want to hit him, but I want less to get hit. With this play, I can't get hit on White's next roll.

13/11* (2), 9/7*, 6/4

My answer and reasons apply to a, b and c.

A)I, frankly, have no idea. My guess is 8/4(2).
B)Hit 2 with 13-7 and cover 6/4 with the last one
C)Hit 2, cover are the easy 3. And then I'm torn between stepping up and slotting the 5 point. I think I'll go with the slot for the final 2.

In Part a), the best strategy is to forego the game, and try to save the gammon. Along the way, White may crack, but very few risks should be taken to force the issue. Black's tactics should be to let White move. Containing White's stragglers is a near impossible task, so anything that delays White is going to make it harder for Black to hold onto his own board. Hitting is counterproductive. Conversely, every additional Black checker that gets hit and sent back increases the odds that Black will lose a double game.

Unfortunately, Black must choose between these competing needs:

• Do not hit: 8/4(2)
  After this play, White can hit with any one. This is eleven shots in thirty-six compared to only one shot with the alternative play. Still, this is the move I like. It is so important to keep White moving that Black must risk having another checker sent back.
  
  
• Hit, in order to minimize White's shots: 13/11*/7*, 6/4
  From the bar, White can hit only with a roll of 1-1. The immediate safety of this move is offset by the increased likelyhood that Black's board will crash sooner.

In Part b), where Black has an escape hatch, his tactics are completely different. With the bar point open, Black should hit, 13/11*/7*, 6/4, and attempt to contain White's checkers. Black is playing a two-way game. He may go forward or backward, depending on the next few rolls.

Part c) could be played the same as Part b). Black has two numbers -- five and six -- with which to launch his back men into the outfield, so a two-way game plan is not out of the question. His triple anchor is so strong, however, that Black should forget about the two-way option, and go all out for the backgame. Some variation of the hara-kiri is in order. I like 9/7*/5, 6/2. I don't want to hit twice; that would slow White down unnecessarily.

My solutions:
Part a): 8/4(2)
Part b): 13/11*/7*
Part c): 9/7*/5, 6/2

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 52%.

Wow when i saw the first one it took a min almost, then yikes there is two more !

OK

A. 13 - 11 and 9 - 5 and 6 - 4

B. 13 - 7 and 6 - 4

C. 13 - 7 and 6 - 4

these were tough and since i own the cube i would probably ask for time and spend more looking at the possible outs great ?'s

Slightly disappointed you made this a cash game problem. Hope you can answer the crawford match game position in the other thread also.

a) I would still play 6/2 6/4(2) because I feel this is the best play for timing and not sending too many men back which I feel is going to only increase our opponents gammons by too large a number. Its a play that more or less "gives up" winning the game and we own the cube which I guess makes it too passive but Im so confused about this spot it is probably what I do over the board.

b) Feels like the easiest to play. Hitting as many as I can while also establishing the 4-point. Playing 13/11*/7* 6/4. Hits 2 on bar and keeping a checker on 13 to maybe hit the blot on 12 also. At the same time creating a 2-point homeboard and also creating timing for my back men to escape to the gap in his prime. If that fails I now have men to make a 3-point prime with rolls like 3-2 and making the barpoint with 4-2 and 3-3.

c) Brings 3 anchors breaking up opponents prime. Id still play 6/4 as my first move. Then hit twice with 13/11* and 9/7* to create that timing we need here. Last deuce Im torn between making the same play as b) or moving the last one up from 23 playing 23/21. Since these are 3 different problems I choose the last option playing 23/21 13/11* 9/7* 6/4 just to make a different answer then b) :P

Hi Bill,

The idea behind the 3 problems is how to get your timing right.

In a) black needs to be hit at least once, thats why i would play 9x7/5 and 8/4,
hoping to be hit with a 4 or an 8, or if not i will leave a midpoint blot alone on the next roll.

In b) the timing of black is better, but he has to throw a 5 soon, I would play 13x11 9x7/5 and 6/4.
Being hit on the 5 is alright here since it has its plusses.

In c) the timing of black is even better, all 2,3,5 and 6 play well, so a regular close out play will be good here:
13x11 9x7 8/4.

greetings k.

8/4(2) is my play in all 3 positions.

It's tempting to do something else in potisions 2 and 3 but as it is our timing is just barely ok, best not to screw it up IMO.

in 1st one over the board I'll play 8/4(2); 6/4 9/3 looks sort of cute but I don't think it'll necessarily be better
2nd one 13/7 6/4

Grunch.


Rumble in the jungle. I stayed awake, 13 years old and saw Ali winning in the early morning hours, after fighting several rounds in the ropes. That is what we fishes are living for: the come back. Thank you, Mr. Robertie for another chapter in this book. I am on nightshift, so little time, but this is yummy.

a) Dead in the ropes. We have 100 pips timing but almost the half behind a six prime. So i see to plans: creating a polish prime, being hit and hope to dance a little bit. Second: dodging with 6/4(2) 6/2, hoping that white throws the doubles. I saw Ali: so i would play: 9/7* 7/5 6/2.
b) Stayin alive. White has a major flaw: the barpoint, almost unpossible to make. So we have a route for reinforcement. Given this, i would simple try to win forward: 13/11*/7*, 6/4. Staying with one man on the midpoint, eventually to rebuild, this will fight also for outfield control.
c) Beat white to the punch. We are playing almost for even money, so life’s a gas: 13/11* 9/7* 7/5 6/4. A zugzwang or zwickmühle: i will have an instant offense or at least a very good timing for my massive back game.

When we were sittin, watching the fight, i got woefully. I was on Alis side. My father consoled me: “I saw him against Sonny Liston, watch out.” That is why we fishes loves back games. Some times, you will come back. Some times, we can feel us like kings. Isn’t a back game sometimes a sort of phantom punch?!

Grunch. Very interesting spots.

a) 8/4(2)
b) 13/11*/7*, 6/4
c) 13/11*/7*, 6/4

I'll already answered in the other thread, so I'll keep my answer for (a), which is hit 2 checkers, make the 4-pt and make the 11-pt. But after reading others' posts, maybe the position is so hopeless that it is better to hope that White rolls big doubles and breaks his prime sooner than later. I thought that somehow we could wish that White gets stucked behind our pseudo prime, but I now believe it's even more unlikely to succeed.

There's more hope in (b) (White's bar point open) and (c) (1-2-4 backgame with at least some tiny bits of timing), but I'm a bit lost about how it would change my approach. Therefore, I would keep my play for (b). For (c), I would try to improve my timing as much as I can, so I would play something like 23/21 (2) 9/7*/5.


(a) 13/11* (2) 9/7* 6/4
(b) 13/11* (2) 9/7* 6/4
(c) 23/21(2) 9/7*/5

a) We're in a bad spot but putting 2 of white's checkers on the bar might give black a chance to block white and force him to break the prime.

Answer - 13/7**, 6/4

b) White's timing is much better in this position than in position a. So even though white doesn't have a 6 prime yet, all black can do is wait things out here. Hitting white would only make things worse for black.

Answer - 6/4, 8/2

c) Here, black's position is a lot stronger than the other 2. Still, there is nothing to be gained by trying to block white. What black can do is try to gain even more timing and cause white to completely dismantle his board. To achieve this, black will hit but he'll leave a bunch of blots in his home board hoping that white has to hit.

Answer - 13/11*, 9/7*, 6/2

A- I'm sticking with my answer from the OP 13/11*/7* 6/4 but I'm not sure this is correct. if it's not then moving up in our home board would be with something like 8/4(2) or 8/4 6/2. either way we're a dog to win.

B- Here I feel 13/11*/7* 6/4 in almost certainly correct or something like it.

C- 23/21 13/11* 9/7* 6/4 feels right here. I want to bring up at least one guy from the 23 point. not 100% certain that leaving the extra pip on the 23 if right in which case 23/21(2) 9/7 6/4 looks best.

a. 13/5**
b. 13/7** 6/4
c. 13/5**

I like the old fasioned massive backgame in a and c, and two way game with chance to make 18pt in b.

Idk I still think that even in position A we should just go for it and hit and slot the world.....Playing 8-4 (2) just loses gammon after gammon anyway with no counterplay at all.

At least hitting and slotting I have some variance to root for

Is it right to abandon ALL forward chances in Part (c) ?

I think it is. The 4-2 backgame is far superior to the 4-1, so I'm wary of the plays that abandon the 23 point. Black has enough timing to hold out for a 3 or a 1. When he rolls either, he should split off the 24 point. A 3 would be ideal, but even if he only rolls a 1, the split to the 23 point will give him both 2s and 3s to move into escape position. I'm also wary of the two-way game. With 6 checkers back, four of which are buried, Black's chances of building a prime to contain White are limited. Black should commit to playing a massive backgame.

On this turn, I'm with Ferrengi, Networth and Sheetsworld. Slot the world. Make a Polish prime. It's hara kiri time. Unfortunately, I'm all alone -- again -- in my choice of plays. Almost certainly, that means I'm wrong! (Again!) My original play was 9/7*/5, 6/2, but now I think that slotting the 2 point is a mistake. If White hits the checker there, all is well. When he misses, however, that checker will be positioned too deep in the home board. Since I'm still opposed to hitting twice, on a do-over, I would play 9/7*/5, 8/4.

What do you think? Should Black keep his forward options open, or should he commit to a massive backgame now?

What's a Polish prime?

One full of defensive holes sandwiched between two aggressive super powers who believe it is theirs would be my best guess.

A prime consisting of blots instead of points.

Do you know if this is by any chance named after the fact that many Eastern Europeans play backgammon with single blots counting as points, thus making primes possible with only six checkers?

All the Polish and Russians seem to play a straight race form of the game with no hitting whatsoever whenever I watch them play (you can only get ahead in the race by priming and forcing players to be unable to move - no hitting possible).

I don't know the origin of the expression, but I would guess is has to do with alliteration and an unfortunate ethnic slur. Come to think of it, I shouldn't have used the phrase.

I think it's more along the lines of "Polish submarine."