FFM19Game 1 move 30: Herd cube action

[Julia_H]

Last time I put the question the Herd thought it too good to cube. With a mix of indirect shots and running numbers, what about this time?

(By the way, I was home very late last night with the MSO bronze medal for 7-pointers... gold and silver were 1 win ahead of me, and I got the nod on a complex tie-break of three players. I bet work will not thank me for being sleepy this morning )

[dorbel]

Spoiler

A nice example of Woolsey's rule. Am I certain that this is a take? I think that I would take it, but I wouldn't bet my house on it,so it must be a double. Or look at it another way, ten hitting numbers and another six get the straggler safe for an overwhelming race lead. That's a lot of volatility. I cube and get ready to take the recube if I get stuck in Red's outfield.

[close]

[ah_clem]

Spoiler

excellent rolls: 61,52,43,63,54
Good rolls: 64, 65, 55, 44
Lousy rolls: everything else

That's sixteen good or excellent rolls and twenty lousy ones.  And he likely has a cube after the lousy ones, which we probably have to eat. I don't want to eat a four cube here.

Moreover, we win a fair amount of gammons after the excellent rolls, but we won't realize the full value if the cube is at 2.  If we were at 4a4a or some other score with an elevated gammon price I'd be more inclined to cube here.

Roll.

[close]

[dorbel]

Spoiler

Look at it this way Clem. Your categories of "Good or excellent" and "lousy" are neither exact terminology nor equally good/bad. They don't have equal weight on the scales. Your "Good or excellent" rolls are all huge market losers, except of course in the rare cases where red manages to hit a fly shot from the bar. The 20 "lousy" rolls break down into two sub categories, 6-2 and 5-3, where we give 11 shots and certainly won't be doubled (not very lousy) and 16 others where we are forced to stay on Red's bar point and leave 23 shots. I think that Red probably does have a double then, but it's such an easy take with his 6pt open that it is hardly a problem. This situation cries out for a cube and I'm not absolutely sure that it's a take!

[close]

[ah_clem]

Spoiler

Look at it this way Clem. Your categories of "Good or excellent" and "lousy" are neither exact terminology nor equally good/bad. They don't have equal weight on the scales. Your "Good or excellent" rolls are all huge market losers, except of course in the rare cases where red manages to hit a fly shot from the bar. The 20 "lousy" rolls break down into two sub categories, 6-2 and 5-3, where we give 11 shots and certainly won't be doubled (not very lousy) and 16 others where we are forced to stay on Red's bar point and leave 23 shots. I think that Red probably does have a double then, but it's such an easy take with his 6pt open that it is hardly a problem. This situation cries out for a cube and I'm not absolutely sure that it's a take!

Well, it looks like a pretty clear take to me.  Granted, I overlooked the four 8s that only leave a single direct shot, but that still leaves 16 shakes that give him 23 shots - the four cube will be ours (his market window opens at 32%) and while I agree with you that it's an easy take it's not something that we actually want.  Our market window opens at 54% AtS and we probably have that plus a lot of market losers so maybe you're right about it being a cube.   I just don't have the appetite to eat a four cube.  A two cube when we throw an airball?  Yeah, I'll be happy to eat that. 

[close]

[KDP]

Spoiler

i would double and let him worry whether or not its a take or not. and like dorbel said im not too worried about a 4 cube coming back to us w/ his 6 pt open and the racing lead we have.

[close]

[ah_clem]

rollout

Spoiler

XG says we have  73% GWC, which is quite a bit higher than I would have estimated.  With that many wins and all those market losers, holding  is a double whopper with cheese.  The take is pretty comfortable AtS since the recube vig is huge.  Reverse the scores and it's a whopper to take (see variant).  I took a quick peek at money play, and it's similar to the otb numbers (double by .332, take by .124)



XGID=-CCCB-C--a-ab-----A-bbbcb-:0:0:1:00:2:1:0:5:10

X:Player 1   O:Player 2
Score is X:2 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    |
|                  |   |                  |
|                  |   |                  |
|                  |BAR|                  |
|                  |   |                  |
|                  |   |                  |
|                  |   | X        X  X  X |
| O                |   | X     X  X  X  X |
| O  O     O       |   | X     X  X  X  X |
+12-11-10--9--8--7-------6--5--4--3--2--1-+
Pip count  X: 62  O: 88 X-O: 2-1/5
Cube: 1
X on roll, cube action

Analyzed in Rollout
No double
  Player Winning Chances:   72.66% (G:10.16% B:0.05%)
  Opponent Winning Chances: 27.34% (G:0.52% B:0.01%)
Double/Take
  Player Winning Chances:   72.53% (G:10.37% B:0.14%)
  Opponent Winning Chances: 27.47% (G:0.36% B:0.01%)

Cubeless Equities: No Double=+0.623, Double=+1.590

Cubeful Equities:
       No double:     +0.602 (-0.270)
       Double/Take:   +0.872
       Double/Pass:   +1.000 (+0.128)

Best Cube action: Double / Take

Rollout:
  1296 Games rolled with Variance Reduction.
  Moves: 3-ply, cube decisions: XG Roller
  Confidence No Double: ± 0.006 (+0.596..+0.608)
  Confidence Double:    ± 0.012 (+0.860..+0.885)

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

  Duration: 49.8 seconds

eXtreme Gammon Version: 2.10, MET: Kazaross XG2

////////////////////////variant -scores reversed ///////////////////////

XGID=-CCCB-C--a-ab-----A-bbbcb-:0:0:1:00:1:2:0:5:10

X:Player 1   O:Player 2
Score is X:1 O:2 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    |
|                  |   |                  |
|                  |   |                  |
|                  |BAR|                  |
|                  |   |                  |
|                  |   |                  |
|                  |   | X        X  X  X |
| O                |   | X     X  X  X  X |
| O  O     O       |   | X     X  X  X  X |
+12-11-10--9--8--7-------6--5--4--3--2--1-+
Pip count  X: 62  O: 88 X-O: 1-2/5
Cube: 1
X on roll, cube action

Analyzed in XG Roller++
Player Winning Chances:   72.60% (G:10.12% B:0.05%)
Opponent Winning Chances: 27.40% (G:0.52% B:0.01%)

Cubeless Equities: No Double=+0.563, Double=+1.295

Cubeful Equities:
       No double:     +0.527 (-0.473)
       Double/Take:   +1.079 (+0.079)
       Double/Pass:   +1.000

Best Cube action: Double / Pass

eXtreme Gammon Version: 2.10, MET: Kazaross XG2

[close]

[socksey]

Spoiler

Without discussion, I would have voted no, but with discussion and analysis, I vote yes.  Is that fair?  How can we go back when voting has already taken place with other scenario?  I think I just want to see this played out.  giggle giggle

[close]

socksey

[dorbel]

This is a very interesting position, because it nicely illustrates the different attitudes towards the cube. One sort of player likes to wait for something good to happen and win with the cube when it happens. The other sort of player likes to get the cube in when there is a very good chance of something good happening and a playable position when it doesn't. The first sort of player likes to think in terms of how likely he is to win the game, but the second, while taking that into account, is more interested in the volatility of the position. How can we measure volatility? Market losing sequences are a good indicator. Any number in the teens is a good indicator that the cube is hot, but it isn't just are they market losers, but by how much do they lose the market? In this position, White loses it a by a lot when she hits or runs to safety. When she fails to hit she has to take a cube, but she has 13 numbers there where Red misses and then White will usually have some shots of her own. What does that look like in real terms? For simplicity I will ignore the numbers where Red is hit but hits a fly shot from the bar and the numbers (which are actually much more likely) where White is hit but enters later and still wins. On this roll White has 16/36 numbers that win immediately and she will win about 50% of the rest. Effectively 26 wins to 10 losses, which is actually exactly what the rollout makes it. Note too that White has some gammons if she hits straight away which win the match nicely.
This is quite an uncommon position, but we often see positions that are effectively similar, where we have a high anchor and attacking chances against blots in our outfield and home. We double so that if our attack works we win a nice doubled gammon and when it doesn't we are still in the game because of our anchor. Our straggler here is a sort of anchor, vulnerable to attack it's true, but able to enter if hit and nicely covering the outfield when it isn't.

[dorbel]

In response to the question "which strategy is the best in the long run?", unquestionably the more aggressive policy. You can liken it to a choice of two paths across a mountain range, one long but relatively safe, one short but dangerous. The long path is tedious and dull, the short path is interesting every step of the way. You will see eagles! Live as you want to live!
If you examine the play of any modern master you will see that they double aggressively. There are no successful modern players who are very conservative cube handlers.

[ah_clem]

This is a very interesting position, because it nicely illustrates the different attitudes towards the cube. One sort of player likes to wait for something good to happen and win with the cube when it happens. The other sort of player likes to get the cube in when there is a very good chance of something good happening and a playable position when it doesn't.

I can't speak for the others who voted to hold, but my (incorrect) decision to hold was not based on "attitude" but rather a mis-judgement or the relative risks and rewards.  I'm normally quite aggressive with the cube, especially at early stages of short matches.  'Get some gammon chances and push the cube' is sound advice in short matches and I have no qualms about making some small cube errors when the mistake is to cube too early.  I think we are in perfect agreement the the time to cube is when something good is about to happen, rather than waiting until after it has happened.

In this case, I saw the very likely probability that we'd be looking at an unappetizing recube almost half the time, so something good was about to happen, but also something bad was equally likely to happen.  How does one weigh that?   

My first hypothesis was that I missed the boat by underestimating our winning chances after being hit (the open six point and the race lead gives us a lot of winning chances from the bar)  so while 'good' and 'bad' might have been equally likely, 'good' is pretty good while 'bad' is not that bad.  But looking at a variant where I moved the open point from the six to the ace it's still a cube (albeit not as strong)

XGID=-CCCB-C--a-ab-----Abbbbc--:0:0:1:00:2:1:0:5:10

X:Player 1   O:Player 2
Score is X:2 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    |
|                  |   |                  |
|                  |   |                  |
|                  |BAR|                  |
|                  |   |                  |
|                  |   |                  |
|                  |   | X        X  X  X |
| O                |   | X     X  X  X  X |
| O  O     O       |   | X     X  X  X  X |
+12-11-10--9--8--7-------6--5--4--3--2--1-+
Pip count  X: 62  O: 98 X-O: 2-1/5
Cube: 1
X on roll, cube action

Analyzed in XG Roller++
Player Winning Chances:   62.76% (G:10.26% B:0.05%)
Opponent Winning Chances: 37.24% (G:1.71% B:0.04%)

Cubeless Equities: No Double=+0.413, Double=+1.084

Cubeful Equities:
       No double:     +0.262 (-0.043)
       Double/Take:   +0.305
       Double/Pass:   +1.000 (+0.695)

Best Cube action: Double / Take

eXtreme Gammon Version: 2.10, MET: Kazaross XG2

So even with a fairly mediocre 63% chance of winning instead of 73%, the abundant market losers still make it a cube. 

O'hagen's law says you probably have a double if you can find 9/36 market losers, provided the non-market losers are not killers.  Here we had 16 market losers, and the non-market losers are not really killer, so ship it. 

BTW, for those observing from the peanut gallery, the fact that we shook an airball and may lose the match because of it does not mean holding was correct here.  Those who voted to hold should not be saying "I told you so."  Holding would have been an error.