XGID=---C-DCBa---bCa--abbbbb---:0:0:1:00:5:2:0:7:10

Score is X:5 O:2 7 pt.(s) match.
+13-14-15-16-17-18------19-20-21-22-23-24-+
| X O O O | | O O O O |
| X O | | O O O O |
| X | | |
| | | |
| | | |
| |BAR| |
| | | |
| | | X |
| | | X X X |
| O X | | X X X |
| O O X | | X X X |
+12-11-10--9--8--7-------6--5--4--3--2--1-+
Pip count X: 100 O: 112 X-O: 5-2/7
Cube: 1
X on roll, cube action

---
Tim Chow

--- SoupGate-Win32 v1.05
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On Wednesday, February 8, 2023 at 10:48:20 AM UTC-5, Tim Chow wrote:

XGID=---C-DCBa---bCa--abbbbb---:0:0:1:00:5:2:0:7:10

Score is X:5 O:2 7 pt.(s) match.
+13-14-15-16-17-18------19-20-21-22-23-24-+
| X O O O | | O O O O |
| X O | | O O O O |
| X | | |
| | | |
| | | |
| |BAR| |
| | | |
| | | X |
| | | X X X |
| O X | | X X X |
| O O X | | X X X |
+12-11-10--9--8--7-------6--5--4--3--2--1-+
Pip count X: 100 O: 112 X-O: 5-2/7
Cube: 1
X on roll, cube action

---
Tim Chow

I wouldn't have too hard a time taking the double. As a race or holding game at this pip count, I *think* O is on the edge of a take. The hit would hurt, but I think that's more than offset by 1) X's open 4 point which will impair bearing off, 2) a nice
bear in structure for O, 3) an excellent board for O if she hits, 4) some chance that O will have a return hit after coming back in.
Initially, I thought it would be hard to send the cube. But since I think O is somewhere in the take/pass border, and given the improbability of gammons, logic tells me it's a double. But that was a circuitous route to that conclusion. I didn't see the
opportunity of a hit as all that advantageous. The thought of how badly things could go for us after a hit is uncomfortable.
Bob

--- SoupGate-Win32 v1.05
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On Wednesday, February 8, 2023 at 10:48:20 AM UTC-5, Tim Chow wrote:

XGID=---C-DCBa---bCa--abbbbb---:0:0:1:00:5:2:0:7:10

Score is X:5 O:2 7 pt.(s) match.
+13-14-15-16-17-18------19-20-21-22-23-24-+
| X O O O | | O O O O |
| X O | | O O O O |
| X | | |
| | | |
| | | |
| |BAR| |
| | | |
| | | X |
| | | X X X |
| O X | | X X X |
| O O X | | X X X |
+12-11-10--9--8--7-------6--5--4--3--2--1-+
Pip count X: 100 O: 112 X-O: 5-2/7
Cube: 1
X on roll, cube action

---
Tim Chow

Everyone who replies to this thread should start with knowing/stating what the opp's (live cube) take point is and estimating how often we win while showing your work. Otherwise you're here just to fuck spiders.

Stick

--- SoupGate-Win32 v1.05
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On Wednesday, February 8, 2023 at 3:12:43 PM UTC-5, Stick Rice wrote:

On Wednesday, February 8, 2023 at 10:48:20 AM UTC-5, Tim Chow wrote:

XGID=---C-DCBa---bCa--abbbbb---:0:0:1:00:5:2:0:7:10

Score is X:5 O:2 7 pt.(s) match. +13-14-15-16-17-18------19-20-21-22-23-24-+
| X O O O | | O O O O |
| X O | | O O O O |
| X | | |
| | | |
| | | |
| |BAR| |
| | | |
| | | X |
| | | X X X |
| O X | | X X X |
| O O X | | X X X |
+12-11-10--9--8--7-------6--5--4--3--2--1-+
Pip count X: 100 O: 112 X-O: 5-2/7
Cube: 1
X on roll, cube action

---
Tim Chow

Everyone who replies to this thread should start with knowing/stating what the opp's (live cube) take point is and estimating how often we win while showing your work. Otherwise you're here just to fuck spiders.

Stick

I'll get in line behind you.
:-)
Bob

--- SoupGate-Win32 v1.05
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On 2/8/2023 3:12 PM, Stick Rice wrote:

Everyone who replies to this thread should start with knowing/stating what the opp's (live cube) take point is and estimating how often we win while showing your work. Otherwise you're here just to fuck spiders.

"Live cube take point" has got to be one of the most absurd
terms in backgammon. The term "live" is especially absurd here.

---
Tim Chow

--- SoupGate-Win32 v1.05
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On Thursday, February 9, 2023 at 8:59:08 AM UTC-5, Timothy Chow wrote:

On 2/8/2023 3:12 PM, Stick Rice wrote:

Everyone who replies to this thread should start with knowing/stating what the opp's (live cube) take point is and estimating how often we win while showing your work. Otherwise you're here just to fuck spiders.

"Live cube take point" has got to be one of the most absurd
terms in backgammon. The term "live" is especially absurd here.

---
Tim Chow

There are times in matches when a cube is taken and it's a dead cube right? And there are times when it's semi dead right? Not sure why you think it's absurd. In this particular position if we could somehow (I'm not going to try) tweak it so that the
hits virtually won the game for the on roll player when he hits the outfield blot and keep or better the win % for the opponent (make the race a lot better for him?) then half the time he'd be taking a dead cube instead of a live one and that would be
worth noting.

Stick

--- SoupGate-Win32 v1.05
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On 2/9/2023 2:42 PM, Stick Rice wrote:

There are times in matches when a cube is taken and it's a dead cube right? And there are times when it's semi dead right? Not sure why you think it's absurd. In this particular position if we could somehow (I'm not going to try) tweak it so that

the hits virtually won the game for the on roll player when he hits the outfield blot and keep or better the win % for the opponent (make the race a lot better for him?) then half the time he'd be taking a dead cube instead of a live one and that would
be worth noting.

First of all, at this particular score, what can "live cube"
possibly mean? The doubler is leading 2-away. It's an
automatic redouble, and then there's no more cube action.
Maybe if it were a last-roll position, and the redouble might
not happen, you could argue that it's a "live cube." Maybe.

Secondly, "live cube take point" makes it sound like it's a
definite thing. But it's not. It depends on the recube vig,
which varies from one position to the next. To be able to
quote a number for the "live cube take point" you have to
do some hocus-pocus mumbo-jumbo about average recube vig or
some such black magic. Unlike the raw take point, it does
not simply depend on the match score and cube location, so
one should not use terminology that conveys that incorrect
impression.

---
Tim Chow

--- SoupGate-Win32 v1.05
* Origin: fsxNet Usenet Gateway (21:1/5)

XGID=---C-DCBa---bCa--abbbbb---:0:0:1:00:5:2:0:7:10

Score is X:5 O:2 7 pt.(s) match.
+13-14-15-16-17-18------19-20-21-22-23-24-+
| X O O O | | O O O O |
| X O | | O O O O |
| X | | |
| | | |
| | | |
| |BAR| |
| | | |
| | | X |
| | | X X X |
| O X | | X X X |
| O O X | | X X X |
+12-11-10--9--8--7-------6--5--4--3--2--1-+
Pip count X: 100 O: 112 X-O: 5-2/7
Cube: 1
X on roll, cube action

The main reason I wanted to post this was because XG 3-ply does
not double as X. O's take point is around 16/68 ~ 23%, which
means that you can pretty much use your money-game instincts.
This rolls out to a pass, but the point is that even though the
double is pretty clear to a human, it's not so clear to XG 3-ply.

Analyzed in Rollout
No double
Player Winning Chances: 77.06% (G:5.52% B:0.05%)
Opponent Winning Chances: 22.94% (G:1.12% B:0.07%)
Double/Take
Player Winning Chances: 77.86% (G:3.91% B:0.02%)
Opponent Winning Chances: 22.14% (G:0.90% B:0.14%)

Cubeful Equities:
No double: +0.898 (-0.102)
Double/Take: +1.062 (+0.062)
Double/Pass: +1.000

Best Cube action: Double / Pass

Rollout:
1296 Games rolled with Variance Reduction.
Dice Seed: 271828
Moves: 3-ply, cube decisions: XG Roller
Confidence No Double: ± 0.006 (+0.892..+0.903)
Confidence Double: ± 0.012 (+1.050..+1.074)

eXtreme Gammon Version: 2.19.211.pre-release, MET: Kazaross XG2

---
Tim Chow

--- SoupGate-Win32 v1.05
* Origin: fsxNet Usenet Gateway (21:1/5)

On Friday, February 10, 2023 at 2:27:31 PM UTC, Timothy Chow wrote:

On 2/9/2023 2:42 PM, Stick Rice wrote:

There are times in matches when a cube is taken and it's a dead cube right? And there are times when it's semi dead right? Not sure why you think it's absurd. In this particular position if we could somehow (I'm not going to try) tweak it so that the

hits virtually won the game for the on roll player when he hits the outfield blot and keep or better the win % for the opponent (make the race a lot better for him?) then half the time he'd be taking a dead cube instead of a live one and that would be
worth noting.

First of all, at this particular score, what can "live cube"
possibly mean? The doubler is leading 2-away. It's an
automatic redouble, and then there's no more cube action.

Tim,

You seem to be implying that, if the doubler is 2 away and the
opponent is more than 2 away, the opponent will always redouble
if they take (assuming it's not a last-roll position).
But this is far from the truth. It's possible (in some positions)
for the doubler to roll such a bad anti-joker that the trailer becomes
too good to redouble.
I can't believe you forgot to mention this scenario. Ok, it only
happens once in every trillion matches. But it should be mentioned
for thoroughness. I think it's a good idea to discuss every single
thing that might happen, no matter how unlikely, because that
way I spend less time worrying about the important stuff that
I'm trying to avoid facing.

Paul

--- SoupGate-Win32 v1.05
* Origin: fsxNet Usenet Gateway (21:1/5)

On 2/11/2023 9:34 AM, peps...@gmail.com wrote:

You seem to be implying that, if the doubler is 2 away and the
opponent is more than 2 away, the opponent will always redouble
if they take (assuming it's not a last-roll position).
But this is far from the truth. It's possible (in some positions)
for the doubler to roll such a bad anti-joker that the trailer becomes
too good to redouble.

Good point, Paul. Below is an example, inspired by this position:

https://www.bkgm.com/rgb/rgb.cgi?view+1479

Note that O has already borne off a checker. After D/T, if X rolls 66,
then O is obviously too good.

XGID=b----GDAAAA--------bbbbbb-:0:0:1:00:3:0:0:5:10

Score is X:3 O:0 5 pt.(s) match.
+13-14-15-16-17-18------19-20-21-22-23-24-+
| | | O O O O O O | O
| | | O O O O O O |
| | | |
| | | |
| | | |
| |BAR| |
| | O | 7 |
| | O | X X |
| | | X X |
| | | X X |
| X X X X | | X X |
+12-11-10--9--8--7-------6--5--4--3--2--1-+
Pip count X: 93 O: 92 X-O: 3-0/5
Cube: 1
X on roll, cube action

Analyzed in Rollout
No double
Player Winning Chances: 75.86% (G:0.00% B:0.00%)
Opponent Winning Chances: 24.14% (G:3.10% B:0.28%)
Double/Take
Player Winning Chances: 76.65% (G:0.00% B:0.00%)
Opponent Winning Chances: 23.35% (G:2.93% B:0.26%)

Cubeful Equities:
No double: +0.833 (-0.131)
Double/Take: +0.965
Double/Pass: +1.000 (+0.035)

Best Cube action: Double / Take

Rollout:
1296 Games rolled with Variance Reduction.
Dice Seed: 271828
Moves: 3-ply, cube decisions: XG Roller
Confidence No Double: ± 0.007 (+0.827..+0.840)
Confidence Double: ± 0.019 (+0.946..+0.983)

eXtreme Gammon Version: 2.19.211.pre-release, MET: Kazaross XG2

---
Tim Chow

--- SoupGate-Win32 v1.05
* Origin: fsxNet Usenet Gateway (21:1/5)

On Sunday, February 12, 2023 at 1:55:51 PM UTC, Timothy Chow wrote:

On 2/11/2023 9:34 AM, peps...@gmail.com wrote:

You seem to be implying that, if the doubler is 2 away and the
opponent is more than 2 away, the opponent will always redouble
if they take (assuming it's not a last-roll position).
But this is far from the truth. It's possible (in some positions)
for the doubler to roll such a bad anti-joker that the trailer becomes
too good to redouble.

Good point, Paul. Below is an example, inspired by this position:

https://www.bkgm.com/rgb/rgb.cgi?view+1479

Note that O has already borne off a checker. After D/T, if X rolls 66,
then O is obviously too good.

XGID=b----GDAAAA--------bbbbbb-:0:0:1:00:3:0:0:5:10

Score is X:3 O:0 5 pt.(s) match.
+13-14-15-16-17-18------19-20-21-22-23-24-+
| | | O O O O O O | O
| | | O O O O O O |
| | | |
| | | |
| | | |
| |BAR| |
| | O | 7 |
| | O | X X |
| | | X X |
| | | X X |
| X X X X | | X X |
+12-11-10--9--8--7-------6--5--4--3--2--1-+
Pip count X: 93 O: 92 X-O: 3-0/5
Cube: 1
X on roll, cube action
Analyzed in Rollout
No double
Player Winning Chances: 75.86% (G:0.00% B:0.00%)
Opponent Winning Chances: 24.14% (G:3.10% B:0.28%)
Double/Take
Player Winning Chances: 76.65% (G:0.00% B:0.00%)
Opponent Winning Chances: 23.35% (G:2.93% B:0.26%)

Cubeful Equities:
No double: +0.833 (-0.131)
Double/Take: +0.965
Double/Pass: +1.000 (+0.035)

Best Cube action: Double / Take
Rollout:
1296 Games rolled with Variance Reduction.
Dice Seed: 271828
Moves: 3-ply, cube decisions: XG Roller
Confidence No Double: ± 0.007 (+0.827..+0.840)
Confidence Double: ± 0.019 (+0.946..+0.983)
eXtreme Gammon Version: 2.19.211.pre-release, MET: Kazaross XG2

Thanks, Tim.
I'm not sure where (perhaps Backgammon Funfair) but I remember
an attempt to find the worst possible roll.
This had exactly the same idea of having the opponent on the bar with
a closed board and being forced to expose four blots with a 66.
Of course, for the worst-roll-variantization, the off-roll player must not
have borne off a checker, so the position can't be exactly the same
as yours but it's surely extremely similar.

Paul

--- SoupGate-Win32 v1.05
* Origin: fsxNet Usenet Gateway (21:1/5)

On Sunday, February 12, 2023 at 1:55:51 PM UTC, Timothy Chow wrote:

On 2/11/2023 9:34 AM, peps...@gmail.com wrote:

You seem to be implying that, if the doubler is 2 away and the
opponent is more than 2 away, the opponent will always redouble
if they take (assuming it's not a last-roll position).
But this is far from the truth. It's possible (in some positions)
for the doubler to roll such a bad anti-joker that the trailer becomes
too good to redouble.

Good point, Paul. Below is an example, inspired by this position:

https://www.bkgm.com/rgb/rgb.cgi?view+1479

Note that O has already borne off a checker. After D/T, if X rolls 66,
then O is obviously too good.

XGID=b----GDAAAA--------bbbbbb-:0:0:1:00:3:0:0:5:10

Score is X:3 O:0 5 pt.(s) match.
+13-14-15-16-17-18------19-20-21-22-23-24-+
| | | O O O O O O | O
| | | O O O O O O |
| | | |
| | | |
| | | |
| |BAR| |
| | O | 7 |
| | O | X X |
| | | X X |
| | | X X |
| X X X X | | X X |
+12-11-10--9--8--7-------6--5--4--3--2--1-+
Pip count X: 93 O: 92 X-O: 3-0/5
Cube: 1
X on roll, cube action
Analyzed in Rollout
No double
Player Winning Chances: 75.86% (G:0.00% B:0.00%)
Opponent Winning Chances: 24.14% (G:3.10% B:0.28%)
Double/Take
Player Winning Chances: 76.65% (G:0.00% B:0.00%)
Opponent Winning Chances: 23.35% (G:2.93% B:0.26%)

Cubeful Equities:
No double: +0.833 (-0.131)
Double/Take: +0.965
Double/Pass: +1.000 (+0.035)

Best Cube action: Double / Take
Rollout:
1296 Games rolled with Variance Reduction.
Dice Seed: 271828
Moves: 3-ply, cube decisions: XG Roller
Confidence No Double: ± 0.007 (+0.827..+0.840)
Confidence Double: ± 0.019 (+0.946..+0.983)
eXtreme Gammon Version: 2.19.211.pre-release, MET: Kazaross XG2

I wonder if your position is reachable by competent play(?)
It's clearly reachable by legal play though.

Paul

--- SoupGate-Win32 v1.05
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On 2/13/2023 4:35 AM, peps...@gmail.com wrote:

On Sunday, February 12, 2023 at 1:55:51 PM UTC, Timothy Chow wrote:

Good point, Paul. Below is an example, inspired by this position:

https://www.bkgm.com/rgb/rgb.cgi?view+1479

I'm not sure where (perhaps Backgammon Funfair) but I remember
an attempt to find the worst possible roll.

Indeed, I found the above link by searching bkgm.com for the
worst or unluckiest roll.

---
Tim Chow

--- SoupGate-Win32 v1.05
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