A Simborg Blunder Quiz

[Simborg]

Today?s blunder is a simple quiz. In the position below, you are playing in a money game and you are white. You just got an excellent roll?5-3. Of course, you have to enter off the bar with the 5, and now you have a 3 to play, and there are only two reasonable choices.

Here are today?s questions:

1. Should you make your 5 point or should you hit your opponent?s blot on your 10 point?
2. If you had rolled double 5 instead, should you hit 1 checker or hit two and leave a blot on your 5 point?
3. If you had rolled 6-6 and could not come in off the bar, what would be the proper cube action for black and if black doubled, what would be the proper cube action for white?





scroll down for the answers and explanation.









Answers:

1. It is better to hit than make your 5 point.
2. It is best to hit 2 checkers.
3. It is double/take.


Explanation:

1. Both hitting and making your 5 point are good plays, and actually, the difference is not that great. After a rollout it is only 4.8 percent better to hit, but keep in mind that a 4.8 error is significant. Make just three of those in one game and you have hurt your chances by 15%. So they add up, and good players are very unhappy with themselves when they make an error of that size. It is often a difficult decision whether to hit or make a point?whether to take the offensive (hit) or defense (anchor by making a point). Often, especially before there is a cube (and gammons are not activated) taking the more aggressive, hitting play is right, because you could get lucky and your opponent may fail to enter on his next roll, putting you in a much more commanding position. Another reason for the hit is simply because of the negatives of your position is you don?t hit. If you make your 5 point, notice that white would not have 7 points total on the board. That means that 14 of his checkers are linked together in twosomes. The next time white rolls, unless it is doubles, something has to give, and when it does, that generally means blots for the opponent. Also, if you don?t hit, look at black?s position. He gets the full use of both dice on his next roll, and he can do a lot of things on that roll including making your 5 point, which would give him a strong holding position; making your 10 point or bar point, which are also decent positions for black, or simply making a point in his outer board that safeties his checkers and gives him a landing place. When you hit, you take away half his roll (or ¼ if he rolls good doubles) and that limits his options.
2. If you roll double 5?s, you have rolled a great Joker, and one that could end the game. Hitting the second checker is risky, because you leave a blot on your 5 point which leaves your opponent a direct shot from the bar. If he rolls a 5, it would not be fun to get hit. But let?s consider the alternatives. What if you didn?t hit and he rolled a 5? In that case, he would have an anchor on your 5 point, and that gives him a strong holding position for the rest of the game. If he makes your 5 point, it would be a long time, and many rolls, before you could possibly have a strong enough lead in the game to double. In fact, if you don?t hit him and he rolls a 5, depending on what is on the other die, he becomes about a 60 percent favorite in the game. If you do hit him and he rolls a 5 and hits you, he is only about a 52 percent favorite, so the game is close to even. But what if he doesn?t roll a 5. If you hit the second checker and he doesn?t roll a 5, even if he comes in and makes his 2 point, you take a commanding lead in the game and have a very strong position. In fact, if he dances with both checkers (fails to enter), you are a 65% favorite and have a double on your next roll. (He has a take, but it?s a scary one, because if you cover your blot on the next roll with a 3 or 8, you will win lots of gammons.) So whether he rolls a 5 or not, you are better off hitting that checker on your 5 point.

Now here is a most interesting question? How is someone who is trying to learn the game of backgammon and improve his game supposed to know that is it better to hit the second checker? The top players know the right play here, and in most situations, not because they are smarter than everyone else (though most of the top players in the world are extremely smart and some have I.Q.?s that are off the charts). Most of them know the right play simply because they ?remember? the situation, or similar situations from the past. They have ?reference-positions? that they know. They have been in this, or similar situations to know that they are much better off hitting the second checker. There are situations where they are better off not to hit the second checker, and they have those reference positions in their head already. But what should those of us who do not have 40 years of experience and a hundred thousand reference positions in our head do when we have a decision like this one? The answer, for me, is to put it in Snowie, look at the percentages if I make one play, look at the percentages if I make the other play, and hope I remember the lesson when it comes up again. (Long ago I wondered exactly how many times I win a gammon when I have two of my opponent?s checkers on the bar and a perfect bearoff position. I put it in Snowie and it say I win a gammon 39.9% of the time. I have never forgotten that and that simple information has helped me decide how much risk to take to try to get that second checker, or how much risk to take in the bearoff.) So the answer to the big question is, every time you study a position thoroughly, and understand the answer, it gets added to your internal reference library. The bigger and better your library, and the better you are able to retrieve the information from that library when you are playing over the board, the better player you will be.

3. The answer to the third question is simple and basic. It is a double for black because he wins the game 66 percent of the time, and about half of those will be gammons. And it is a take for white, even though he loses 66 percent of the time and gets gammoned half of those, he wins enough of the time (and he wins gammons about 9 percent of the time himself) to make it a higher net equity parlay to take than to pass and simply lose a point.