This is the first of a short series of problems in which making
the 5pt is one of the options.

XGID=--a---EbC--CdB---cad-B----:0:0:1:63:0:0:0:0:10

X:Player 1 O:Player 2
Score is X:0 O:0. Unlimited Game
+13-14-15-16-17-18------19-20-21-22-23-24-+
| X O O | | O X |
| X O | | O X |
| O | | O |
| | | O |
| | | |
| |BAR| |
| | | X |
| O | | X |
| O X X | | X |
| O X X O | | X |
| O X X O | | X O |
+12-11-10--9--8--7-------6--5--4--3--2--1-+
Pip count X: 155 O: 166 X-O: 0-0
Cube: 1
X to play 63

---
Tim Chow

On Wednesday, October 26, 2022 at 1:34:25 PM UTC+1, Tim Chow wrote:
> This is the first of a short series of problems in which making
> the 5pt is one of the options.
>
> XGID=--a---EbC--CdB---cad-B----:0:0:1:63:0:0:0:0:10
>
> X:Player 1 O:Player 2
> Score is X:0 O:0. Unlimited Game
> +13-14-15-16-17-18------19-20-21-22-23-24-+
> | X O O | | O X |
> | X O | | O X |
> | O | | O |
> | | | O |
> | | | |
> | |BAR| |
> | | | X |
> | O | | X |
> | O X X | | X |
> | O X X O | | X |
> | O X X O | | X O |
> +12-11-10--9--8--7-------6--5--4--3--2--1-+
> Pip count X: 155 O: 166 X-O: 0-0
> Cube: 1
> X to play 63
>
> ---
> Tim Chow

I think I know the rule.
You make the 5 point unless it's obviously wrong to make the 5 point, unless the position's an obvious exception.
Is that correct?

Paul

On Wednesday, October 26, 2022 at 1:34:25 PM UTC+1, Tim Chow wrote:
> This is the first of a short series of problems in which making
> the 5pt is one of the options.
>
> XGID=--a---EbC--CdB---cad-B----:0:0:1:63:0:0:0:0:10
>
> X:Player 1 O:Player 2
> Score is X:0 O:0. Unlimited Game
> +13-14-15-16-17-18------19-20-21-22-23-24-+
> | X O O | | O X |
> | X O | | O X |
> | O | | O |
> | | | O |
> | | | |
> | |BAR| |
> | | | X |
> | O | | X |
> | O X X | | X |
> | O X X O | | X |
> | O X X O | | X O |
> +12-11-10--9--8--7-------6--5--4--3--2--1-+
> Pip count X: 155 O: 166 X-O: 0-0
> Cube: 1
> X to play 63
>
> ---
> Tim Chow

I would definitely make the 5 point here. Hitting on the 18 point
should clearly be considered but I'm stuck for a good 6 if I do that.
Hitting twice gains something, but the 5 point seems worth so much more.

5 point here, for me, with a lot of confidence.

Paul

On 10/26/2022 8:34 AM, Timothy Chow wrote:
> This is the first of a short series of problems in which making
> the 5pt is one of the options.
>
> XGID=--a---EbC--CdB---cad-B----:0:0:1:63:0:0:0:0:10
>
> X:Player 1   O:Player 2
> Score is X:0 O:0. Unlimited Game
>  +13-14-15-16-17-18------19-20-21-22-23-24-+
>  | X           O  O |   | O     X          |
>  | X           O    |   | O     X          |
>  |             O    |   | O                |
>  |                  |   | O                |
>  |                  |   |                  |
>  |                  |BAR|                  |
>  |                  |   | X                |
>  | O                |   | X                |
>  | O  X        X    |   | X                |
>  | O  X        X  O |   | X                |
>  | O  X        X  O |   | X           O    |
>  +12-11-10--9--8--7-------6--5--4--3--2--1-+
> Pip count  X: 155  O: 166 X-O: 0-0
> Cube: 1
> X to play 63

X will bu up by 20 pips after this play so I don't see the need to take
unnecessary risks. So, I'll make the five point here.

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

On Wednesday, October 26, 2022 at 8:34:25 AM UTC-4, Tim Chow wrote:
> This is the first of a short series of problems in which making
> the 5pt is one of the options.
>
> XGID=--a---EbC--CdB---cad-B----:0:0:1:63:0:0:0:0:10
>
> X:Player 1 O:Player 2
> Score is X:0 O:0. Unlimited Game
> +13-14-15-16-17-18------19-20-21-22-23-24-+
> | X O O | | O X |
> | X O | | O X |
> | O | | O |
> | | | O |
> | | | |
> | |BAR| |
> | | | X |
> | O | | X |
> | O X X | | X |
> | O X X O | | X |
> | O X X O | | X O |
> +12-11-10--9--8--7-------6--5--4--3--2--1-+
> Pip count X: 155 O: 166 X-O: 0-0
> Cube: 1
> X to play 63
>
> ---
> Tim Chow

I can't believe people are making the five here. This is an 'obvious exception'. You make your five point you aren't attacking anything, you aren't priming anything...oh wait, you are semi priming yourself by allowing the opponent to make his bar point/five point while you have two men anchored on the 21pt, a 20 pip racing lead and a rough road escaping since you didn't do it now. Yes, making the 5pt should be the default in general but another default is in the early game when you have a better board or nobody has a board yet you hit normal things. By hitting especially on the other side of the board you do things like gain a ton of pips in the race, escape your back checkers, and remove the fear of both being primed or attacked.

Stick

On 10/26/2022 3:54 PM, Stick Rice wrote:

>
> I can't believe people are making the five here. This is an 'obvious exception'. You make your five point you aren't attacking anything, you aren't priming anything...oh wait, you are semi priming yourself by allowing the opponent to make his bar point/five point while you have two men anchored on the 21pt, a 20 pip racing lead and a rough road escaping since you didn't do it now. Yes, making the 5pt should be the default in general but another default is in the early game when you have a better board or nobody has a board yet you hit normal things. By hitting especially on the other side of the board you do things like gain a ton of pips in the race, escape your back checkers, and remove the fear of both being primed or attacked.
>
> Stick

Thanks. I've added this piece of wisdom to my list.

On Thursday, October 27, 2022 at 4:13:43 PM UTC+1, ah...Clem wrote:
> On 10/26/2022 3:54 PM, Stick Rice wrote:
>
> >
> > I can't believe people are making the five here. This is an 'obvious exception'. You make your five point you aren't attacking anything, you aren't priming anything...oh wait, you are semi priming yourself by allowing the opponent to make his bar point/five point while you have two men anchored on the 21pt, a 20 pip racing lead and a rough road escaping since you didn't do it now. Yes, making the 5pt should be the default in general but another default is in the early game when you have a better board or nobody has a board yet you hit normal things. By hitting especially on the other side of the board you do things like gain a ton of pips in the race, escape your back checkers, and remove the fear of both being primed or attacked.
> >
> > Stick
> Thanks. I've added this piece of wisdom to my list.
Are any of the items in the list available for sharing?

On 10/27/2022 2:06 PM, peps...@gmail.com wrote:
> On Thursday, October 27, 2022 at 4:13:43 PM UTC+1, ah...Clem wrote:

>> Thanks. I've added this piece of wisdom to my list.
> Are any of the items in the list available for sharing?

It's a work in progress. Comments cheerfully accepted.

https://docs.google.com/document/d/1kL8S4H7rJaAHnUhrTJc0fGcIH5-eo7cMXqvvt6-wWig/edit?usp=sharing

On Thursday, October 27, 2022 at 9:17:40 PM UTC+1, ah...Clem wrote:
> On 10/27/2022 2:06 PM, peps...@gmail.com wrote:
> > On Thursday, October 27, 2022 at 4:13:43 PM UTC+1, ah...Clem wrote:
>
> >> Thanks. I've added this piece of wisdom to my list.
> > Are any of the items in the list available for sharing?
> It's a work in progress. Comments cheerfully accepted.
>
> https://docs.google.com/document/d/1kL8S4H7rJaAHnUhrTJc0fGcIH5-eo7cMXqvvt6-wWig/edit?usp=sharing

I haven't read this in detail, but I'm impressed by this effort.
I remember your posts from when you first started posting (or at least when I first became aware of them),
and it's clear that you've improved massively over the years.
I somehow think of you as being around the same strength as me, but I don't have evidence for this --
you may well be far better.

Paul

XGID=--a---EbC--CdB---cad-B----:0:0:1:63:0:0:0:0:10

X:Player 1 O:Player 2
Score is X:0 O:0. Unlimited Game
+13-14-15-16-17-18------19-20-21-22-23-24-+
| X O O | | O X |
| X O | | O X |
| O | | O |
| | | O |
| | | |
| |BAR| |
| | | X |
| O | | X |
| O X X | | X |
| O X X O | | X |
| O X X O | | X O |
+12-11-10--9--8--7-------6--5--4--3--2--1-+
Pip count X: 155 O: 166 X-O: 0-0
Cube: 1
X to play 63

There's no reason not to hit here. Yes, it breaks X's high anchor,
but O is in no position to counterattack. Making the 5pt has less
value when O has anchored (if you can call it that) on our bar point.

After 21/18*, there remains a question of whether to hit twice.
I rolled out the position at gammon go (see below) and the double
hit came out slightly ahead, but for money, XG plays 21/15.

1. Rollout¹ 21/15 21/18* eq:+0.339
Player: 57.95% (G:16.82% B:0.76%)
Opponent: 42.05% (G:10.15% B:0.41%)
Confidence: ±0.018 (+0.322..+0.357) - [100.0%]

2. Rollout¹ 21/18* 8/2* eq:+0.290 (-0.049)
Player: 56.33% (G:18.36% B:0.69%)
Opponent: 43.67% (G:10.57% B:0.48%)
Confidence: ±0.016 (+0.274..+0.307) - [0.0%]

3. Rollout¹ 11/5 8/5 eq:+0.236 (-0.103)
Player: 55.82% (G:13.86% B:0.40%)
Opponent: 44.18% (G:8.37% B:0.34%)
Confidence: ±0.013 (+0.223..+0.249) - [0.0%]

¹ 1296 Games rolled with Variance Reduction.
Dice Seed: 271828
Moves: 3-ply, cube decisions: XG Roller

eXtreme Gammon Version: 2.19.207.pre-release

---------
Gammon go
---------

XGID=--a---EbC--CdB---cad-B----:0:0:1:63:0:1:1:2:10

Score is X:0 O:1 2 pt.(s) match.
+13-14-15-16-17-18------19-20-21-22-23-24-+
| X O O | | O X |
| X O | | O X |
| O | | O |
| | | O |
| | | |
| |BAR| |
| | | X |
| O | | X |
| O X X | | X |
| O X X O | | X |
| O X X O | | X O |
+12-11-10--9--8--7-------6--5--4--3--2--1-+
Pip count X: 155 O: 166 X-O: 0-1/2 Crawford
Cube: 1
X to play 63

1. Rollout¹ 21/18* 8/2* eq:+0.472
Player: 57.78% (G:15.84% B:1.52%)
Opponent: 42.22% (G:10.51% B:1.42%)
Confidence: ±0.009 (+0.464..+0.481) - [100.0%]

2. Rollout¹ 21/15 21/18* eq:+0.452 (-0.020)
Player: 60.30% (G:12.30% B:1.68%)
Opponent: 39.70% (G:8.78% B:0.97%)
Confidence: ±0.008 (+0.444..+0.460) - [0.0%]

¹ 1296 Games rolled with Variance Reduction.
Dice Seed: 271828
Moves: 3-ply, cube decisions: XG Roller

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

---
Tim Chow

On Thursday, October 27, 2022 at 4:17:40 PM UTC-4, ah...Clem wrote:
> On 10/27/2022 2:06 PM, peps...@gmail.com wrote:
> > On Thursday, October 27, 2022 at 4:13:43 PM UTC+1, ah...Clem wrote:
>
> >> Thanks. I've added this piece of wisdom to my list.
> > Are any of the items in the list available for sharing?
> It's a work in progress. Comments cheerfully accepted.
>
> https://docs.google.com/document/d/1kL8S4H7rJaAHnUhrTJc0fGcIH5-eo7cMXqvvt6-wWig/edit?usp=sharing

There are many points I'd like cleaned up, attributed correctly, or flat out deleted but the only thing I must insist on is it's O'Hagan, not O'Hagen.

Stick

On Friday, October 28, 2022 at 4:33:11 PM UTC+1, Stick Rice wrote:
> On Thursday, October 27, 2022 at 4:17:40 PM UTC-4, ah...Clem wrote:
> > On 10/27/2022 2:06 PM, peps...@gmail.com wrote:
> > > On Thursday, October 27, 2022 at 4:13:43 PM UTC+1, ah...Clem wrote:
> >
> > >> Thanks. I've added this piece of wisdom to my list.
> > > Are any of the items in the list available for sharing?
> > It's a work in progress. Comments cheerfully accepted.
> >
> > https://docs.google.com/document/d/1kL8S4H7rJaAHnUhrTJc0fGcIH5-eo7cMXqvvt6-wWig/edit?usp=sharing
> There are many points I'd like cleaned up, attributed correctly, or flat out deleted but the only thing I must insist on is it's O'Hagan, not O'Hagen.
>
> Stick

I've heard the one about not doubling with a one-point board, but I haven't heard it called "Dimitri's Rule" and there are _tons_ of exceptions.

Paul

On Friday, October 28, 2022 at 12:19:25 PM UTC-4, peps...@gmail.com wrote:
> On Friday, October 28, 2022 at 4:33:11 PM UTC+1, Stick Rice wrote:
> > On Thursday, October 27, 2022 at 4:17:40 PM UTC-4, ah...Clem wrote:
> > > On 10/27/2022 2:06 PM, peps...@gmail.com wrote:
> > > > On Thursday, October 27, 2022 at 4:13:43 PM UTC+1, ah...Clem wrote:
> > >
> > > >> Thanks. I've added this piece of wisdom to my list.
> > > > Are any of the items in the list available for sharing?
> > > It's a work in progress. Comments cheerfully accepted.
> > >
> > > https://docs.google.com/document/d/1kL8S4H7rJaAHnUhrTJc0fGcIH5-eo7cMXqvvt6-wWig/edit?usp=sharing
> > There are many points I'd like cleaned up, attributed correctly, or flat out deleted but the only thing I must insist on is it's O'Hagan, not O'Hagen.
> >
> > Stick
> I've heard the one about not doubling with a one-point board, but I haven't heard it called "Dimitri's Rule" and there are _tons_ of exceptions.
>
> Paul

I've never heard someone say not to cube with only a one point board. In fact, I know I did a series somewhere called 'Pointless Doubles' where obviously we examined when you could/should cube with only a one point board. On the surface to me it seems like a lame rule. Like how often does it come up that you think about doubling without any additional points made? And when it does, it's probably more like to fit into a situation that you could/should be doubling.

Stick

On 10/28/2022 2:59 PM, Stick Rice wrote:
> I've never heard someone say not to cube with only a one point board. In fact, I know I did a series somewhere called 'Pointless Doubles' where obviously we examined when you could/should cube with only a one point board. On the surface to me it seems like a lame rule. Like how often does it come up that you think about doubling without any additional points made? And when it does, it's probably more like to fit into a situation that you could/should be doubling.

Below is a position that I encountered recently which I thought
was a clear take.

XGID=aaaaA-DBB---cD-A-cAe------:0:0:1:00:0:0:0:0:10

Score is X:0 O:0. Unlimited Game
+13-14-15-16-17-18------19-20-21-22-23-24-+
| X X O X | | O |
| X O | | O |
| X O | | O |
| X | | O |
| | | O |
| |BAR| |
| | O | |
| | | X |
| O | | X |
| O X X | | X |
| O X X | | X X O O O |
+12-11-10--9--8--7-------6--5--4--3--2--1-+
Pip count X: 143 O: 187 X-O: 0-0
Cube: 1
X on roll, cube action

Analyzed in Rollout
No double
Player Winning Chances: 68.97% (G:30.26% B:2.81%)
Opponent Winning Chances: 31.03% (G:5.66% B:0.25%)
Double/Take
Player Winning Chances: 68.78% (G:30.34% B:2.89%)
Opponent Winning Chances: 31.22% (G:5.80% B:0.25%)

Cubeful Equities:
No double: +0.909 (-0.091)
Double/Take: +1.050 (+0.050)
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: ± 0.015 (+0.894..+0.925)
Confidence Double: ± 0.020 (+1.029..+1.070)

eXtreme Gammon Version: 2.19.211.pre-release

---
Tim Chow

On Saturday, October 29, 2022 at 4:22:43 PM UTC+1, Tim Chow wrote:
> On 10/28/2022 2:59 PM, Stick Rice wrote:
> > I've never heard someone say not to cube with only a one point board. In fact, I know I did a series somewhere called 'Pointless Doubles' where obviously we examined when you could/should cube with only a one point board. On the surface to me it seems like a lame rule. Like how often does it come up that you think about doubling without any additional points made? And when it does, it's probably more like to fit into a situation that you could/should be doubling.
> Below is a position that I encountered recently which I thought
> was a clear take.
>
> XGID=aaaaA-DBB---cD-A-cAe------:0:0:1:00:0:0:0:0:10
> Score is X:0 O:0. Unlimited Game
> +13-14-15-16-17-18------19-20-21-22-23-24-+
> | X X O X | | O |
> | X O | | O |
> | X O | | O |
> | X | | O |
> | | | O |
> | |BAR| |
> | | O | |
> | | | X |
> | O | | X |
> | O X X | | X |
> | O X X | | X X O O O |
> +12-11-10--9--8--7-------6--5--4--3--2--1-+
> Pip count X: 143 O: 187 X-O: 0-0
> Cube: 1
> X on roll, cube action
>
> Analyzed in Rollout
> No double
> Player Winning Chances: 68.97% (G:30.26% B:2.81%)
> Opponent Winning Chances: 31.03% (G:5.66% B:0.25%)
> Double/Take
> Player Winning Chances: 68.78% (G:30.34% B:2.89%)
> Opponent Winning Chances: 31.22% (G:5.80% B:0.25%)
>
> Cubeful Equities:
> No double: +0.909 (-0.091)
> Double/Take: +1.050 (+0.050)
> 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: ± 0.015 (+0.894..+0.925)
> Confidence Double: ± 0.020 (+1.029..+1.070)
>

One of the problems with myself (though unfortunately not the
largest problem) is that when I see a play or cube action that's interesting,
I sometimes immediately post about it while giving away the answer, forgoing the
chance to post the problem as a quiz to this delightful forum.

I thought it was only me who did that.

Paul

On Saturday, October 29, 2022 at 11:22:43 AM UTC-4, Tim Chow wrote:
> On 10/28/2022 2:59 PM, Stick Rice wrote:
> > I've never heard someone say not to cube with only a one point board. In fact, I know I did a series somewhere called 'Pointless Doubles' where obviously we examined when you could/should cube with only a one point board. On the surface to me it seems like a lame rule. Like how often does it come up that you think about doubling without any additional points made? And when it does, it's probably more like to fit into a situation that you could/should be doubling.
> Below is a position that I encountered recently which I thought
> was a clear take.
>
> XGID=aaaaA-DBB---cD-A-cAe------:0:0:1:00:0:0:0:0:10
> Score is X:0 O:0. Unlimited Game
> +13-14-15-16-17-18------19-20-21-22-23-24-+
> | X X O X | | O |
> | X O | | O |
> | X O | | O |
> | X | | O |
> | | | O |
> | |BAR| |
> | | O | |
> | | | X |
> | O | | X |
> | O X X | | X |
> | O X X | | X X O O O |
> +12-11-10--9--8--7-------6--5--4--3--2--1-+
> Pip count X: 143 O: 187 X-O: 0-0
> Cube: 1
> X on roll, cube action
>
> Analyzed in Rollout
> No double
> Player Winning Chances: 68.97% (G:30.26% B:2.81%)
> Opponent Winning Chances: 31.03% (G:5.66% B:0.25%)
> Double/Take
> Player Winning Chances: 68.78% (G:30.34% B:2.89%)
> Opponent Winning Chances: 31.22% (G:5.80% B:0.25%)
>
> Cubeful Equities:
> No double: +0.909 (-0.091)
> Double/Take: +1.050 (+0.050)
> 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: ± 0.015 (+0.894..+0.925)
> Confidence Double: ± 0.020 (+1.029..+1.070)
>
> eXtreme Gammon Version: 2.19.211.pre-release
>
> ---
> Tim Chow

Honestly I'd have thought it was a bigger pass. We see not cubing is a smallish error (in comparison to the general size a cube error can be) because a large percentage of the time next turn it's still D/P.

Stick