| |
BGonline.org Forums
3a-7a cube action
Posted By: John O'Hagan In Response To: 3a-7a cube action (Dmitriy Obukhov)
Date: Thursday, 15 July 2010, at 2:11 a.m.
Every roll is a cube decision, so it's good that you stopped to think about it. Lots of your losses will be match ending g's which will cost you the match with the cube on 2 or 4, so recubing is worth a look. I'll guess that 2/3 of your losses will be g's so redoubling only costs when you lose a single game. A single loss with the cube on 2 makes the score 0-6 Crawford with about 9% MWC so the loss is a third of that or 3%. Now for the gain from redoubling: I guess that 3/8 of your wins are gammons since D4 is real gammonish along with 64 or 41 + a fan. A single win with the cube on 2/4 gives you about 35%/50% MWC, a gain of 15% MWC. 5/8 of 15% is 9.33%. A gammon win with a 2/4 cube gives you 50%/100% MWC, a gain of 50% MWC. 3/8 of 50% is a little less than 19%. So the gain from redoubling is 9.33% + 19% = 28.33%. The redoubling window therefore opens at 3/3 + 28.33, a little less than 10% and closes when White has a marginal take/pass. If White drops, he's up 4-2 with about 65% MWC, takes and loses a single ties the score at 4-4 with 50% MWC, takes and loses a g loses the match with 0% MWC, takes and win wins the match with 100% MWC. So White's 4-cube takepoint is around 30% plus 100% of Black's gammon chances. How many gammons does Black win here? I'll estimate around 3/36, a little over 8%. So White's takepoint is 38% which means Black's window closes at 62%.
Black's certainly over 10% in this position but he's also nowhere near 62%. I'll guess he wins around 8/36 from this position, around 22%. When you're that low in the window, redoubling is usually not right unless you have a fairly large number of big market losers. I think you're a little short of big mkt losers here - just D4 plus 64 or 41 plus a fan. That's only 2.8/36. Notice that the other entering 4s aren't market losers at all - 45 and 43 leave a direct while 42 blots on the ace. Redoubling would probably be indicated if all 4s were likely big mkt losers. Another argument against redoubling is that you're far from gin to be g'd even if you get 2 men closed out in this position. With 2 closed out along with 2 on the 10 and 2 on the 8, I think you save the g around 30% of the time. Redoubling would more likely be correct if an even higher fraction of your losses were gammons.
NR/T.
| |
BGonline.org Forums is maintained by Stick with WebBBS 5.12.