XGID=--aa--D-C--AdD---d-c-b--BA:0:0:1:36:0:0:3:0:10

X:Player 1 O:Player 2
Score is X:0 O:0. Unlimited Game, Jacoby Beaver
+13-14-15-16-17-18------19-20-21-22-23-24-+
| X O | | O O X |
| X O | | O O X |
| X O | | O |
| X O | | |
| | X | |
| |BAR| |
| | | |
| O | | X |
| O X | | X |
| O X | | X |
| O X X | | X O O |
+12-11-10--9--8--7-------6--5--4--3--2--1-+
Pip count X: 184 O: 155 X-O: 0-0
Cube: 1
X to play 36

--
Ah....Clem
The future is fun, the future is fair.

On 8/23/2022 10:51 AM, ah....Clem wrote:
>
>
> XGID=--aa--D-C--AdD---d-c-b--BA:0:0:1:36:0:0:3:0:10
>
> X:Player 1   O:Player 2
> Score is X:0 O:0. Unlimited Game, Jacoby Beaver
>  +13-14-15-16-17-18------19-20-21-22-23-24-+
>  | X           O    |   | O     O        X |
>  | X           O    |   | O     O        X |
>  | X           O    |   | O                |
>  | X           O    |   |                  |
>  |                  | X |                  |
>  |                  |BAR|                  |
>  |                  |   |                  |
>  | O                |   | X                |
>  | O           X    |   | X                |
>  | O           X    |   | X                |
>  | O  X        X    |   | X        O  O    |
>  +12-11-10--9--8--7-------6--5--4--3--2--1-+
> Pip count  X: 184  O: 155 X-O: 0-0
> Cube: 1
> X to play 36
>

My first instinct is to play bar/16, but we're far behind in the
pip count, so running is probably the wrong idea. Although it
looks a bit loose to slot with 11/5, it's at least the right
strategic idea: with more checkers back and an anchor, we can
afford some boldness, and we'd like to form a prime. It's a
double shot but 3's are duplicated. I'll try 11/5.

---
Tim Chow

ah....Clem wrote:

>
>
>XGID=--aa--D-C--AdD---d-c-b--BA:0:0:1:36:0:0:3:0:10
>
>X:Player 1 O:Player 2
>Score is X:0 O:0. Unlimited Game, Jacoby Beaver
> +13-14-15-16-17-18------19-20-21-22-23-24-+
> | X O | | O O X |
> | X O | | O O X |
> | X O | | O |
> | X O | | |
> | | X | |
> | |BAR| |
> | | | |
> | O | | X |
> | O X | | X |
> | O X | | X |
> | O X X | | X O O |
> +12-11-10--9--8--7-------6--5--4--3--2--1-+
>Pip count X: 184 O: 155 X-O: 0-0
>Cube: 1
>X to play 36

My play would be Bar/22, 24/18. Let's force O to protect the 18-point
and with two separated checkers in his home I may be able to hit back.

On Tuesday, August 23, 2022 at 9:57:39 PM UTC-4, Tim Chow wrote:
> On 8/23/2022 10:51 AM, ah....Clem wrote:
> >
> >
> > XGID=--aa--D-C--AdD---d-c-b--BA:0:0:1:36:0:0:3:0:10
> >
> > X:Player 1 O:Player 2
> > Score is X:0 O:0. Unlimited Game, Jacoby Beaver
> > +13-14-15-16-17-18------19-20-21-22-23-24-+
> > | X O | | O O X |
> > | X O | | O O X |
> > | X O | | O |
> > | X O | | |
> > | | X | |
> > | |BAR| |
> > | | | |
> > | O | | X |
> > | O X | | X |
> > | O X | | X |
> > | O X X | | X O O |
> > +12-11-10--9--8--7-------6--5--4--3--2--1-+
> > Pip count X: 184 O: 155 X-O: 0-0
> > Cube: 1
> > X to play 36
> >
> My first instinct is to play bar/16, but we're far behind in the
> pip count, so running is probably the wrong idea. Although it
> looks a bit loose to slot with 11/5, it's at least the right
> strategic idea: with more checkers back and an anchor, we can
> afford some boldness, and we'd like to form a prime. It's a
> double shot but 3's are duplicated. I'll try 11/5.
>
> ---
> Tim Chow

I would play bar/16 but would not call it a 'running play'.

Stick

On Thursday, August 25, 2022 at 8:45:53 AM UTC+1, Stick Rice wrote:
> On Tuesday, August 23, 2022 at 9:57:39 PM UTC-4, Tim Chow wrote:
> > On 8/23/2022 10:51 AM, ah....Clem wrote:
> > >
> > >
> > > XGID=--aa--D-C--AdD---d-c-b--BA:0:0:1:36:0:0:3:0:10
> > >
> > > X:Player 1 O:Player 2
> > > Score is X:0 O:0. Unlimited Game, Jacoby Beaver
> > > +13-14-15-16-17-18------19-20-21-22-23-24-+
> > > | X O | | O O X |
> > > | X O | | O O X |
> > > | X O | | O |
> > > | X O | | |
> > > | | X | |
> > > | |BAR| |
> > > | | | |
> > > | O | | X |
> > > | O X | | X |
> > > | O X | | X |
> > > | O X X | | X O O |
> > > +12-11-10--9--8--7-------6--5--4--3--2--1-+
> > > Pip count X: 184 O: 155 X-O: 0-0
> > > Cube: 1
> > > X to play 36
> > >
> > My first instinct is to play bar/16, but we're far behind in the
> > pip count, so running is probably the wrong idea. Although it
> > looks a bit loose to slot with 11/5, it's at least the right
> > strategic idea: with more checkers back and an anchor, we can
> > afford some boldness, and we'd like to form a prime. It's a
> > double shot but 3's are duplicated. I'll try 11/5.
> >
> > ---
> > Tim Chow
> I would play bar/16 but would not call it a 'running play'.

That's correct. It's actually a walking play. When you run, you
aim to get somewhere fast. Since we leave two in the inner board,
we are emerging slowly not fast and so this is a walking play.
It can also be called a dawdling play or a somnambulant play.

I've been having all sorts of spills and thrills, slotting to the opponent's bar point
when I don't know what else to do and when it isn't obviously wrong.
[Of course, this really asks for a Stickism. "No, it is absolutely obviously wrong.
It should be obvious to anyone..."]

24/18 for me.

Paul

On Wednesday, August 24, 2022 at 2:10:26 PM UTC+1, badgolferman wrote:
> ah....Clem wrote:
>
> >
> >
> >XGID=--aa--D-C--AdD---d-c-b--BA:0:0:1:36:0:0:3:0:10
> >
> >X:Player 1 O:Player 2
> >Score is X:0 O:0. Unlimited Game, Jacoby Beaver
> > +13-14-15-16-17-18------19-20-21-22-23-24-+
> > | X O | | O O X |
> > | X O | | O O X |
> > | X O | | O |
> > | X O | | |
> > | | X | |
> > | |BAR| |
> > | | | |
> > | O | | X |
> > | O X | | X |
> > | O X | | X |
> > | O X X | | X O O |
> > +12-11-10--9--8--7-------6--5--4--3--2--1-+
> >Pip count X: 184 O: 155 X-O: 0-0
> >Cube: 1
> >X to play 36
> My play would be Bar/22, 24/18. Let's force O to protect the 18-point
> and with two separated checkers in his home I may be able to hit back.
I would do that too, but I Walted your post before making my own decision.

Paul

On Thursday, August 25, 2022 at 8:45:53 AM UTC+1, Stick Rice wrote:
> On Tuesday, August 23, 2022 at 9:57:39 PM UTC-4, Tim Chow wrote:
> > On 8/23/2022 10:51 AM, ah....Clem wrote:
> > >
> > >
> > > XGID=--aa--D-C--AdD---d-c-b--BA:0:0:1:36:0:0:3:0:10
> > >
> > > X:Player 1 O:Player 2
> > > Score is X:0 O:0. Unlimited Game, Jacoby Beaver
> > > +13-14-15-16-17-18------19-20-21-22-23-24-+
> > > | X O | | O O X |
> > > | X O | | O O X |
> > > | X O | | O |
> > > | X O | | |
> > > | | X | |
> > > | |BAR| |
> > > | | | |
> > > | O | | X |
> > > | O X | | X |
> > > | O X | | X |
> > > | O X X | | X O O |
> > > +12-11-10--9--8--7-------6--5--4--3--2--1-+
> > > Pip count X: 184 O: 155 X-O: 0-0
> > > Cube: 1
> > > X to play 36
> > >
> > My first instinct is to play bar/16, but we're far behind in the
> > pip count, so running is probably the wrong idea. Although it
> > looks a bit loose to slot with 11/5, it's at least the right
> > strategic idea: with more checkers back and an anchor, we can
> > afford some boldness, and we'd like to form a prime. It's a
> > double shot but 3's are duplicated. I'll try 11/5.
> >
> > ---
> > Tim Chow
> I would play bar/16 but would not call it a 'running play'.
>
> Stick
I just googled it a bit.
Stick's point on the terminology seems correct.
"Running play" surely means "checker play preparing for a running game", although I
haven't seen that stated explicitly.
In a position where we're so far from being able to run successfully, we don't have a "running play".
The standard opening 65 is a running play because it only leaves a single checker back that we need
to run.

Paul

On 8/25/2022 3:45 AM, Stick Rice wrote:

> I would play bar/16 but would not call it a 'running play'.

What would the Nactation 63R mean in this position? This is
a genuine question because I don't remember the exact definitions.
I think bar/22 24/18 would be 63U.

---
Tim Chow

On Thursday, August 25, 2022 at 12:48:07 PM UTC+1, Tim Chow wrote:
> On 8/25/2022 3:45 AM, Stick Rice wrote:
>
> > I would play bar/16 but would not call it a 'running play'.
> What would the Nactation 63R mean in this position? This is
> a genuine question because I don't remember the exact definitions.
> I think bar/22 24/18 would be 63U.
>
> ---
> Tim Chow

63R would mean bar/16, from my understanding.
As I see it, Nactation relies on the "Nactators" having significant backgammon experience.
It's not a totally objective notation system suitable for universal use like a chess notation system would be.

I think the idea is that you imagine talking about the move and ask yourself what word you would use,
Would the word be "run", "split", "slot" etc?
Here you might say I run with bar/16.

But you said (something like) "It's a running play and ... [positional commentary]"
In that context, I would expect "running play" to be defined as "move preparing to run my checkers home."
In which case, I don't think your play is a running play.
In the context of looking for a Nactation, your play would be a running play.
Different contexts, different interpretations.

Suppose a player has a significant other, and is playing backgammon in the evening, and suddenly remembers that
they had promised to be home by 7pm. In that case, they might suddenly run home, after hastily negotiating their debts
or payments.
In this case, because they "run home", the previous checker play was necessarily a running play, even if it was 8/5 6/5.

Paul

On 8/25/2022 8:54 AM, peps...@gmail.com wrote:
> But you said (something like) "It's a running play and ... [positional commentary]"

I did not use the term "running play." Nor did Stick actually
say that I used the term "running play."

---
Tim Chow

My take was that all four options seemed playable, so I invoked Pottle's
law to settle on bar/16. That's favored by the rollout, but only at
the 91% confidence level after 5484 games.

I can't say I understand why Pottle's law works as often as it does.

In the variant, I've improved O's position by making the defensive five
point; XG then favor's Tim's idea of hanging back and slotting a forward
point.

XGID=--aa--D-C--AdD---d-c-b--BA:0:0:1:63:0:0:3:0:10

X:Player 1 O:Player 2
Score is X:0 O:0. Unlimited Game, Jacoby Beaver
+13-14-15-16-17-18------19-20-21-22-23-24-+
| X O | | O O X |
| X O | | O O X |
| X O | | O |
| X O | | |
| | X | |
| |BAR| |
| | | |
| O | | X |
| O X | | X |
| O X | | X |
| O X X | | X O O |
+12-11-10--9--8--7-------6--5--4--3--2--1-+
Pip count X: 184 O: 155 X-O: 0-0
Cube: 1
X to play 63

1. Rollout¹ Bar/16 eq:-0.580
Player: 38.11% (G:8.03% B:0.35%)
Opponent: 61.89% (G:23.06% B:2.04%)
Confidence: ±0.009 (-0.589..-0.571) - [91.0%]
Duration: 5 hours 17 minutes

2. Rollout¹ Bar/22 24/18 eq:-0.590 (-0.010)
Player: 37.80% (G:8.32% B:0.37%)
Opponent: 62.20% (G:26.79% B:2.39%)
Confidence: ±0.012 (-0.602..-0.578) - [9.0%]
Duration: 2 hours 42 minutes

3. Rollout¹ Bar/22 11/5 eq:-0.604 (-0.024)
Player: 38.12% (G:8.23% B:0.36%)
Opponent: 61.88% (G:24.19% B:2.33%)
Confidence: ±0.009 (-0.613..-0.594) - [0.0%]
Duration: 4 hours 56 minutes

4. Rollout¹ Bar/22 8/2* eq:-0.609 (-0.029)
Player: 37.59% (G:8.55% B:0.34%)
Opponent: 62.41% (G:24.04% B:2.44%)
Confidence: ±0.010 (-0.619..-0.599) - [0.0%]
Duration: 6 hours 41 minutes

¹ 5484 Games rolled with Variance Reduction.
Moves: 3-ply, cube decisions: XG Roller

eXtreme Gammon Version: 2.10

/**************************
/variant
/**************************

XGID=-----bD-C--AdD---d-c-b--BA:0:0:1:63:0:0:3:0:10

X:Player 1 O:Player 2
Score is X:0 O:0. Unlimited Game, Jacoby Beaver
+13-14-15-16-17-18------19-20-21-22-23-24-+
| X O | | O O X |
| X O | | O O X |
| X O | | O |
| X O | | |
| | X | |
| |BAR| |
| | | |
| O | | X |
| O X | | X |
| O X | | X O |
| O X X | | X O |
+12-11-10--9--8--7-------6--5--4--3--2--1-+
Pip count X: 184 O: 150 X-O: 0-0
Cube: 1
X to play 63

1. Rollout¹ Bar/22 13/7 eq:-0.818
Player: 34.19% (G:6.17% B:0.27%)
Opponent: 65.81% (G:26.53% B:2.93%)
Confidence: ±0.021 (-0.839..-0.797) - [99.8%]
Duration: 7 minutes 09 seconds

2. Rollout¹ Bar/16 eq:-0.860 (-0.042)
Player: 33.36% (G:5.67% B:0.23%)
Opponent: 66.64% (G:26.21% B:2.26%)
Confidence: ±0.018 (-0.878..-0.841) - [0.2%]
Duration: 6 minutes 35 seconds

3. XG Roller++ Bar/22 24/18 eq:-0.888 (-0.070)
Player: 33.87% (G:5.61% B:0.17%)
Opponent: 66.13% (G:27.40% B:2.05%)

4. XG Roller++ Bar/22 8/2 eq:-0.969 (-0.151)
Player: 31.54% (G:5.52% B:0.18%)
Opponent: 68.46% (G:25.74% B:2.38%)

¹ 1296 Games rolled with Variance Reduction.
Moves: 3-ply, cube decisions: XG Roller

eXtreme Gammon Version: 2.10

--
Ah....Clem
The future is fun, the future is fair.

On 8/26/2022 4:07 PM, ah....Clem wrote:
> My take was that all four options seemed playable, so I invoked Pottle's
> law to settle on bar/16.  That's favored by the rollout,  but only at
> the 91% confidence level after 5484 games.
>
> I can't say I understand why Pottle's law works as often as it does.

I hate to sound like a card-carrying member of Stick's Terminology
Police, but this really isn't an example of Pottle's law. Pottle's
law says, "Always run the last checker." Bar/16 does not run the last
checker.

Pottle's law is generally taken to apply when you have only one checker
back, but even if you stretched the meaning and tried to apply it here,
it would refer to bar/22 24/18 and not bar/16, since the checker on the
22pt cannot be called the "last checker" when there are two checkers on
the 24pt.

---
Tim Chow

On 8/26/2022 9:23 PM, Timothy Chow wrote:
> On 8/26/2022 4:07 PM, ah....Clem wrote:
>> My take was that all four options seemed playable, so I invoked
>> Pottle's law to settle on bar/16.  That's favored by the rollout,  but
>> only at the 91% confidence level after 5484 games.
>>
>> I can't say I understand why Pottle's law works as often as it does.
>
> I hate to sound like a card-carrying member of Stick's Terminology
> Police, but this really isn't an example of Pottle's law.  Pottle's
> law says, "Always run the last checker."  Bar/16 does not run the last
> checker.
>
> Pottle's law is generally taken to apply when you have only one checker
> back, but even if you stretched the meaning and tried to apply it here,
> it would refer to bar/22 24/18 and not bar/16, since the checker on the
> 22pt cannot be called the "last checker" when there are two checkers on
> the 24pt.

I seem to recall reading somewhere that Pottle's law said "Unless you
have something constructive to do elsewhere, pick up the rearmost
checker and run it as far as you can."

But I can't find that now, and "last" is not the same as "rearmost", so
I stand corrected.

I'm wondering if the variant above has some general validity. For now,
we can call it the "Generalized Pottle Hypothesis". Clearly, there are
many exceptions.

On 8/27/2022 10:09 AM, ah...Clem wrote:
> I seem to recall reading somewhere that Pottle's law said "Unless you
> have something constructive to do elsewhere, pick up the rearmost
> checker and run it as far as you can."
>
> But I can't find that now, and "last" is not the same as "rearmost", so
> I stand corrected.
>
> I'm wondering if the variant above has some general validity. For now,
> we can call it the "Generalized Pottle Hypothesis". Clearly, there are
> many exceptions.

IMO, Pottle's law as usually conceived (with only one checker back) is
backed by two general strategic ideas.

1. If you're ahead or equal in the pip count, and your opponent has one
or more checkers back, then you typically gain a lot by converting to a
position in which you have no checkers back. This potential gain is
usually worth exposing your last checker to a double shot, or sometimes
even a triple shot.

2. If you're equal or behind in the pip count, and your opponent has no
checkers back, it can sometimes still be right to run the last checker
in order to cut your losses (either single or gammon losses), because a
lone checker is usually vulnerable to attack.

I think that #1 is the more common scenario. What I often see are
players who are afraid to run the last checker into a double shot,
because they underestimate how much they gain if they are missed and
they also underestimate the danger of having their last checker
trapped and/or attacked.

In terms of generalization, jumping into the opponent's outfield into a
double or triple shot is something that I see a lot of players balking
at, even when it is urgent that they do so. But, I wouldn't call this
a "Generalized Pottle Hypothesis" because the underlying principle is
not the same as for the usual Pottle's law.

---
Tim Chow