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i see most are in favour of a recube here but
i think by recubing here we risk losing the match unnecessarily, whereas if we hold on, we have a good chance of going 3-1 up and a downside of 3-1, but staying in the match.

i redouble here, even IF we fail to clear the bar, he still has to hit us, the open 6 and our racing lead i think would give him pause about taking i believe. ship it over and let him make the hard decision.

If this were a straight race, Linus would have something like 10% GWC.  The Trice point is 8, Linus is 6 pips behind that.   At 2% per pip that's 12% lower than the money takepoint of ~22%.


But this is not a straight race. We leave a shot with any ace other than 16 (that's 9 shakes) plus 23 24 & 33.   That's 14 shot-leaving rolls. But Linus has to hit; generously giving him 1/3 to hit, we can approximate his hit rate as 14/36 * 1/3 or about 5/36 for 14% or so.  Then he has to contain the hit checker which won't be 100% successful.  But even ignoring that, adding the 10% racing wins and the (overestimated) 14% hitting wins he's nowhere near his takepoint of 33%.

If the cube was centered, he'd be near the 20% takepoint and I'd have to sharpen my pencil for the above calculations.

But since this is a clear drop, we win very few gammons, and there are a number of bad sequences we should recube.

Redouble.

Quote from: stog on April 21, 2013, 10:04:04 AM
i see most are in favour of a recube here but
i think by recubing here we risk losing the match unnecessarily, whereas if we hold on, we have a good chance of going 3-1 up and a downside of 3-1, but staying in the match.

If we win this game we'll be at 2a 4a for a MWC of 67%.  We're about 80% to win this game, so playing this game for the match would be better for us.  I'd love to play this game for the match, but of course this is why Linus should pass.

A good one for Woolsey's rule: are you sure it's a take? If there's some doubt in your mind about the take, ship it. I think 21 rolls get us safely home with a large lead in the race. 15 rolls leave a blot that gets hit about 1/3 of the times, so only 5/36 overall to get hit here. And even then we may still win with a quick 6. If you didn't redouble here, were you sure that Linus can take this? If you weren't, you should have recubed and be done with it.

Massive cube and even more massive pass.  AtS, Linus needs 33% to take a recube and he's nowhere near that.

As for my hypothesis that it might be a take with a centred cube, that's not the case.  Linus doesn't even have the ~20% to take a centered cube.



XGID=-BCBCBBb-----A------bcccb-:1:1:1:00:1:1:0:5:3

X:Herd   O:Linus
Score is X:1 O:1 5 pt.(s) match.
+13-14-15-16-17-18------19-20-21-22-23-24-+
| X                |   |    O  O  O  O  O |
|                  |   |    O  O  O  O  O |
|                  |   |       O  O  O    |
|                  |   |                  |
|                  |   |                  |
|                  |BAR|                  |
|                  |   |                  |
|                  |   |                  |
|                  |   |       X     X    | +---+
|                O |   | X  X  X  X  X  X | | 2 |
|                O |   | X  X  X  X  X  X | +---+
+12-11-10--9--8--7-------6--5--4--3--2--1-+
Pip count  X: 61  O: 75 X-O: 1-1/5
Cube: 2, X own cube
X on roll, cube action

Analyzed in Rollout
No redouble
  Player Winning Chances:   82.18% (G:0.33% B:0.00%)
  Opponent Winning Chances: 17.82% (G:0.12% B:0.00%)
Redouble/Take
  Player Winning Chances:   82.23% (G:0.47% B:0.00%)
  Opponent Winning Chances: 17.77% (G:0.06% B:0.00%)

Cubeless Equities: No Double=+0.648, Double=+1.910

Cubeful Equities:
       No redouble:     +0.797 (-0.203)
       Redouble/Take:   +1.910 (+0.910)
       Redouble/Pass:   +1.000

Best Cube action: Redouble / Pass

Rollout:
  1296 Games rolled with Variance Reduction.
  Moves: 3-ply, cube decisions: XG Roller
  Confidence No Double: ± 0.002 (+0.795..+0.799)
  Confidence Double:    ± 0.002 (+1.908..+1.913)

  Double Decision confidence: 100.0%
  Take Decision confidence: 100.0%

  Duration: 31.1 seconds

eXtreme Gammon Version: 2.10, MET: Kazaross XG2



////////////////////variant - centered cube///////////////

XGID=-BCBCBBb-----A------bcccb-:0:0:1:00:1:1:0:5:3

X:Player 1   O:Player 2
Score is X:1 O:1 5 pt.(s) match.
+13-14-15-16-17-18------19-20-21-22-23-24-+
| X                |   |    O  O  O  O  O |
|                  |   |    O  O  O  O  O |
|                  |   |       O  O  O    |
|                  |   |                  |
|                  |   |                  |
|                  |BAR|                  |
|                  |   |                  |
|                  |   |                  |
|                  |   |       X     X    |
|                O |   | X  X  X  X  X  X |
|                O |   | X  X  X  X  X  X |
+12-11-10--9--8--7-------6--5--4--3--2--1-+
Pip count  X: 61  O: 75 X-O: 1-1/5
Cube: 1
X on roll, cube action

Analyzed in XG Roller+
Player Winning Chances:   82.14% (G:0.34% B:0.00%)
Opponent Winning Chances: 17.86% (G:0.16% B:0.00%)

Cubeless Equities: No Double=+0.645, Double=+1.524

Cubeful Equities:
       No double:     +0.717 (-0.283)
       Double/Take:   +1.280 (+0.280)
       Double/Pass:   +1.000

Best Cube action: Double / Pass

eXtreme Gammon Version: 2.10, MET: Kazaross XG2