We had a great turnout last Sunday for the 2nd “Tour of Patios” backgammon tournament at Bar Bar. 17 players came out to play, and play we did! We ended up running 8 total brackets, and ended up with 8 different winners! Congratulations to Dave, Kyle, me, Steven, Paul, Nick, Bodger, and Cam on the wins!
I did not end up using my overhead camera set-up this time, but I did take pictures of a number of interesting positions that came up. This first one is a cube decision and a variation that came out of my first round match against Nick (who came out for the first time in quite a while, it was good to see him again…)
I’m leading 1-0 in our match to 5, but score doesn’t seem to matter in the bit I have played with this on the machine. I did not do a full pip-count over the board, but I am clearly ahead in the race. What I actually did was count cross-overs to get to bear-off: I have 14, Nick has 17. That is, each of his checkers in my homeboard need to do 3 cross-overs to reach his homeboard, those in my outfield need 2 each, etc. Anyway – I have the race lead. My position isn’t amazing but his is terrible, having just had to split a checker off his 3 point to his ace point to avoid leaving a direct shot. And in terms of threats, well – there’s always double 1’s, 2’s, and 3’s but I am not too worried about hitting loose on my 4 point. So I have position (a little), race (a lot), and threat (a smidge) – should be a double and a pass. And it is! It would have only been about -0.025 error to not double, but the drop is huge -0.430 or so mega-monster blunder to take. Nick then pointed out that if he still had his 3 point made, he thought it would be a take, and it is!
One checker, moved two pips, makes an enormous difference! Now it would be about a -0.105 blunder to not double, but also a -0.044 error to drop! With the fourth point made on his home board, my threats are completely neutralized – hitting loose would be suicidal. I thought that was a great observation, and the kind of thing that I love about this game: a seemingly small change that is, in fact, a huge difference!
The next couple of positions were from that same match, one game later. After a lot of standoffs, we eventually got into a race and in the bear-off I faced the doubling decision below:
In these kinds of positions, I have been using a technique called the Keith Count to guide my decisions. Here, with perfect rolling but without doubles, I need 4 rolls to get off, but Nick needs only 3. On the other hand, that’s not likely. He’s got a double gap, and I have a gap on the 2 point. So it’s complex. My Keith Count is 33 and a bit, his is 29, so the difference is 4 and a bit. I often ignore the “and a bit” part of that, but a difference of 4 is the cut-off between doubling and not doubling, so here that “and a bit” matters. I decided to roll on. Which is correct by a lot! If I doubled and he took, my equity drops by 0.095, putting a double into the category of a blunder (unless he made an even bigger blunder by passing, but he confirmed that he would have taken here).
A couple of rolls later, I faced the following position:
Again, perfect rolls would make this a two-roll versus two-roll position, which is a double/pass. But we both have gaps, so it will more likely take 3 rolls each, but 3-roll versus 3-roll is also a double/pass. Keith Count puts me at 19 and a bit, him at 16, for a difference of 3 and a bit, which is a double and a take. So, I doubled. I think I would have doubled just based on it being kind of 3-roll versus 3-roll, but having learned the Keith Count made me far more confident about the move, which is correct! Not doubling would have been about a -0.18 blunder.
The last position is a checker play decision that came up in my match against Kyle. As you can probably guess from the position, there’d been a fair amount of hitting early on in this game…
This 6-3 roll provides me with a lot of choices! I can anchor on his 5 point, safety the blot on the 14 point, make my own 3 point, and probably a dozen other things! I looked at making my 3 point (9/3, 6/3), on grounds that it strengthens my board and the other side is a mess anyway. I looked at 20/14, 9/6 on grounds that it cleans up almost everything. But ultimately, I went with 23/20 as the strongest use of the 3, which left 14/8 as the strongest use of the 6. When I ran it through the machine, I was glad to see that I was right, but I was also shocked to see that everything else was a massive blunder! The second best move was 23/20, 9/3, which I didn’t even look at, and that’s a -0.195 double-blunder!
Anyway: as I mentioned, we ran 8 brackets, and so play went until around 6pm. I actually left before the last two brackets had resolved, and relied on the players to report back to me afterwards. It was a great afternoon of backgammon. See you all at the next one!