After a bit of a break, Position of the Week is back – and to encourage more weird and wonderful problems, we’re adding a bit of a twist. I will run each position past a small panel, some leading players and some (ok, me) rather less so, who will give me their decision unknown to the rest. Then – and only then – I’ll get XG to cast its silicon-based mind over it and see how much equity it takes away from the experts. We’ll run this until the end of August and whoever submits the position that prompts the biggest mistakes will get an honourable mention at the UK Open… so keep your eyes open for positions of interest and get sending them in to me at julia@ukbgf.com !
First up, one from Mark Dixon taken from his first round against Simon Morecroft in this weekend’s Scope charity tournament:
The question could easily be “how on earth did you get in this position in the first place?” – Blue coming within a roll of being double-backgammoned before picking up Black’s last three men. Having done so, though, the next question is What is the correct cube action for both players? Put your answers in the comments below…
This one certainly caught out the panel, who (apart from me, and I’m a notable coward) elected to ship the cube across, with Black taking.
As it stands, Black’s pure racing chances are pretty poor, being 12 long crossovers from home. Most of his chances come from picking up a shot, which he will do around 35% of the time from here – similar to a conventional acepoint game, but with the advantage of not having to worry about being gammoned by staying to the bitter end. That suggests a pretty easy take. Blue can hold the cube safely for a turn or two as Black shouldn’t even start thinking about passing until Blue has safely cleared his six-point and taken a couple of men off – even then, Black might be interested if Blue’s distribution is particularly awkward.
Doubling with a centred cube would be a -0.091 error, but holding a 2-cube it costs Blue a painful -0.331.
I should add that my rough calculations have black’s takepoint at around 18%.
I can’t see any reason why you would double at this point. I’d take without a seconds thought and probably recube immediately.
I don’t know this one, but this is my thought process.
First, if blue does cube, black won’t need much to recube. I will assume black gets in a recube for all of his wins and half of his loses. This gives black about a 22% takepoint, about the same as a money game with recube vig.
An alternate position is the same except that black’s 12 checkers that are borne off are spread out in black’s homeboard, Blue wins 50% gammons. Black has to do a little more in the above position to win the game than he has to do to in the alternate position to get off the gammon. My best guess is blue wins 77%. Given that is very close to the takepoint, I will guess double/take.
If black had 2 checkers closed out, his winning chances would be around 32%. This is a reference position, that I know. I don’t know if 3 on the ace is better than 2 closed out, but I am guessing that it is. At this score, this must be a massive no redouble and a very easy take.