Doubling Cube Action

In the actual game, White redoubled and I was Black, playing against several players, and I took. My opponent’s laughed at me as the rolled a 6-5 and hit me, but they were not laughing very long when I immediately rolled a 6, hit back, and then, I did not redouble. Instead, I played on and picked up White’s other two checkers and won a gammon.

Afterwards two of my opponents told me how lucky I was, and that I should never have taken the double. After a few heated words, I bet that it was a take and we settled the bet the way we always do…by putting it into Snowie (backgammon computer program) to see what the real expert had to say.

As you can see below, Snowie said it was not only a take…it was not even a double! In fact, Snowie said it was such a bad double, it was actually a Beaver (I should have turned the cube to 8 immediately upon being doubled).

The interesting thing is that this “looks” like a big double at first, and many players would drop this cube if doubled. But like everything else in backgammon, you have to do the math. In the actual game, the players on the White side were so excited to see the double shot they all instantly grabbed the cube and redoubled.

I, on the other hand, was not very happy that I left a double shot, and I was not about to act very quickly or emotionally. I knew I had to do the math, and that’s what I did. 

White certainly is a big favorite if he hits on his next roll, and it sure looks like a lot of hits. But let’s count the hits. White hits with all 1’s…that’s 11 times, and with all 5’s, and that’s 9 more times (you can’t count 1-5 twice). He also hits with 3-2, and that’s 2 more times. So there are a total of 22 hits. 

As we know, there are 36 possible rolls, so that means that 14 times White doesn’t hit. And what happens if White doesn’t hit? Well, down 27 pips, unless his miss is with a 6-6 he gets redoubled immediately and is forced to drop and lose the game. Even if he rolls 6-6, while he doesn’t get redoubled, he is still losing.

So Black has a take just on the 14 misses, as that is well over 25 percent and with the White 6-point open, Black is not likely to get gammoned. 

As you saw, however, if things go wrong, White certainly can get gammoned, and even more important to the cube decision, if Black get’s hit and rolls a 6 immediately, he has a very strong chance of winning the game. So out of those 22 times he gets hit, 11/36, or about 6 times, he comes back in immediately and is probably favored to win again. So that reduces White’s wins to about 16 instead of 22, and since 18 is the half-way number, White is actually an underdog in this position, and that, plus the gammon odds, is what makes this cube a beaver.

The lesson here is that, as always, you have to do the math. A bigger lesson is not to let emotions get the best of you…Backgammon can be a very exciting game, and people tend to make the biggest mistakes right after a particularly good or bad roll that changes the nature of the game. All too often I see people give the cube when they should not…sometimes because they are not good enough to cube, as was this case in this situation, and sometimes because they are “too good” and should play on for the gammon.