Othello has a well-deserved reputation for crafting excellent and
difficult checker-play quizzes. Typical features of his problems
include:

1. Only one play is not a blunder, according to the bot.

2. There are several plausible choices. Rarely does Othello set
a problem where there are only two candidates that a human would
consider.

3. The positions are normal-looking ones, not contrived monstrosities.

Does the position below qualify? Stick, of course, sees only one play,
so he would say that condition 2 is violated. To make the problem
interesting for Stick, I invite him to suggest a variant; I'd be curious
to see whether he comes up with the same variant. I will reveal that my variant differs from the original position by 2 pips.

XGID=-b--B-E-C-A-bB---bbdc-A-A-:0:0:1:61:0:0:0:0:10

Score is X:0 O:0. Unlimited Game
+13-14-15-16-17-18------19-20-21-22-23-24-+
| X O O | | O O X X |
| X O O | | O O |
| | | O O |
| | | O |
| | | |
| |BAR| |
| | | X |
| | | X |
| X | | X |
| O X | | X X O |
| O X X | | X X O |
+12-11-10--9--8--7-------6--5--4--3--2--1-+
Pip count X: 144 O: 143 X-O: 0-0
Cube: 1
X to play 61

---
Tim Chow

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

On Thursday, November 17, 2022 at 9:28:09 AM UTC-5, Tim Chow wrote:

Othello has a well-deserved reputation for crafting excellent and
difficult checker-play quizzes. Typical features of his problems
include:

1. Only one play is not a blunder, according to the bot.

2. There are several plausible choices. Rarely does Othello set
a problem where there are only two candidates that a human would
consider.

3. The positions are normal-looking ones, not contrived monstrosities.

Does the position below qualify? Stick, of course, sees only one play,
so he would say that condition 2 is violated. To make the problem interesting for Stick, I invite him to suggest a variant; I'd be curious
to see whether he comes up with the same variant. I will reveal that my variant differs from the original position by 2 pips.

XGID=-b--B-E-C-A-bB---bbdc-A-A-:0:0:1:61:0:0:0:0:10

Score is X:0 O:0. Unlimited Game
+13-14-15-16-17-18------19-20-21-22-23-24-+
| X O O | | O O X X |
| X O O | | O O |
| | | O O |
| | | O |
| | | |
| |BAR| |
| | | X |
| | | X |
| X | | X |
| O X | | X X O |
| O X X | | X X O |
+12-11-10--9--8--7-------6--5--4--3--2--1-+
Pip count X: 144 O: 143 X-O: 0-0
Cube: 1
X to play 61

---
Tim Chow

You're not wrong, it took me all of 2 seconds to make the play. I hardly remember a next on the Othello quizzes. I don't think this position is very variant friendly but imagine if you're trying to make the original play wrong and underline the
reasoning you'll probably advance the opp's anchor from the 24pt to the 23pt.

Stick

--- SoupGate-Win32 v1.05
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On 11/17/2022 10:13 AM, Stick Rice wrote:

I hardly remember a next on the Othello quizzes.

Each year, I usually find one problem, or perhaps two problems,
on the Othello quiz easy. For example, on the 2022 quiz, I
found problem 5 to be a next.

https://groups.google.com/g/rec.games.backgammon/c/B1tskeAOiuk/m/JMMlswH3AQAJ

---
Tim Chow

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

On Thursday, November 17, 2022 at 9:24:24 PM UTC-5, Tim Chow wrote:

On 11/17/2022 10:13 AM, Stick Rice wrote:

I hardly remember a next on the Othello quizzes.

Each year, I usually find one problem, or perhaps two problems,
on the Othello quiz easy. For example, on the 2022 quiz, I
found problem 5 to be a next.

https://groups.google.com/g/rec.games.backgammon/c/B1tskeAOiuk/m/JMMlswH3AQAJ

---
Tim Chow

I guess I also draw a distinction between a next and a next I don't even have to think about seeing the correct play and knowing it's right in the blink of an eye. While your #5 is obvious/next, I wouldn't know at first glance as I did with this problem.

Stick

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

On 11/18/2022 5:06 AM, Stick Rice wrote:

I guess I also draw a distinction between a next and a next I don't even have to think about seeing the correct play and knowing it's right in the blink of an eye. While your #5 is obvious/next, I wouldn't know at first glance as I did with this

problem.

I still think that you'd categorize some Othello problems in
this way if you saw them again. The reason you remember Othello
quizzes as tough may partly be because you weren't as good a player
(say) 15 years ago as you are today. Here's a problem from 2005.


XGID=-b---AD-C--AcD---c-e--b-B-:0:0:1:45:2:1:0:5:10

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 X |
| X O | | O O X |
| X O | | O |
| X | | O |
| | | O |
| |BAR| |
| | | |
| | | X |
| O X | | X |
| O X | | X O |
| O X X | | X X O |
+12-11-10--9--8--7-------6--5--4--3--2--1-+
Pip count X: 164 O: 147 X-O: 2-1/5
Cube: 1
X to play 45


And here's one from 2004.


XGID=-b--A-E-E---bB---cacbb-B--:0:0:1:11:0:0:1:0:10

Score is X:0 O:0. Unlimited Game, Jacoby
+13-14-15-16-17-18------19-20-21-22-23-24-+
| X O O | | O O O X |
| X O | | O O O X |
| O | | O |
| | | |
| | | |
| |BAR| |
| X | | X |
| X | | X |
| 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: 146 O: 141 X-O: 0-0
Cube: 1
X to play 11

---
Tim Chow

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

On Friday, November 18, 2022 at 8:39:40 AM UTC-5, Tim Chow wrote:

On 11/18/2022 5:06 AM, Stick Rice wrote:

I guess I also draw a distinction between a next and a next I don't even have to think about seeing the correct play and knowing it's right in the blink of an eye. While your #5 is obvious/next, I wouldn't know at first glance as I did with this

problem.

I still think that you'd categorize some Othello problems in
this way if you saw them again. The reason you remember Othello
quizzes as tough may partly be because you weren't as good a player
(say) 15 years ago as you are today. Here's a problem from 2005.

XGID=-b---AD-C--AcD---c-e--b-B-:0:0:1:45:2:1:0:5:10

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 X |
| X O | | O O X |
| X O | | O |
| X | | O |
| | | O |
| |BAR| |
| | | |
| | | X |
| O X | | X |
| O X | | X O |
| O X X | | X X O |
+12-11-10--9--8--7-------6--5--4--3--2--1-+
Pip count X: 164 O: 147 X-O: 2-1/5
Cube: 1
X to play 45

And here's one from 2004.

XGID=-b--A-E-E---bB---cacbb-B--:0:0:1:11:0:0:1:0:10

Score is X:0 O:0. Unlimited Game, Jacoby +13-14-15-16-17-18------19-20-21-22-23-24-+
| X O O | | O O O X |
| X O | | O O O X |
| O | | O |
| | | |
| | | |
| |BAR| |
| X | | X |
| X | | X |
| 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: 146 O: 141 X-O: 0-0
Cube: 1
X to play 11

---
Tim Chow

Maybe you're taking my 'hardly remember' in a different way than I meant it. I meant it in the sense that I feel there was a next here or there over the years but certainly couldn't be expected. From gut memory I do feel like for me personally there
was a next or two over the years on early game play specifically.

Stick

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

XGID=-b--B-E-C-A-bB---bbdc-A-A-:0:0:1:61:0:0:0:0:10

Score is X:0 O:0. Unlimited Game
+13-14-15-16-17-18------19-20-21-22-23-24-+
| X O O | | O O X X |
| X O O | | O O |
| | | O O |
| | | O |
| | | |
| |BAR| |
| | | X |
| | | X |
| X | | X |
| O X | | X X O |
| O X X | | X X O |
+12-11-10--9--8--7-------6--5--4--3--2--1-+
Pip count X: 144 O: 143 X-O: 0-0
Cube: 1
X to play 61

Stick correctly guessed the variant I had prepared---see below.

1. Rollout¹ 22/16 6/5 eq:-0.412
Player: 41.39% (G:13.10% B:0.84%)
Opponent: 58.61% (G:26.67% B:2.16%)
Confidence: ±0.007 (-0.420..-0.405) - [100.0%]

2. Rollout¹ 22/16 10/9 eq:-0.486 (-0.074)
Player: 39.31% (G:12.07% B:0.76%)
Opponent: 60.69% (G:25.56% B:1.40%)
Confidence: ±0.007 (-0.494..-0.479) - [0.0%]

3. Rollout² 24/23 22/16 eq:-0.497 (-0.085)
Player: 38.67% (G:11.57% B:0.67%)
Opponent: 61.33% (G:24.37% B:1.26%)
Confidence: ±0.014 (-0.511..-0.484) - [0.0%]

4. Rollout² 13/7 8/7 eq:-0.499 (-0.087)
Player: 39.01% (G:11.90% B:0.91%)
Opponent: 60.99% (G:26.09% B:2.28%)
Confidence: ±0.015 (-0.514..-0.484) - [0.0%]

5. Rollout² 22/15 eq:-0.514 (-0.102)
Player: 38.90% (G:11.71% B:0.63%)
Opponent: 61.10% (G:24.19% B:1.25%)
Confidence: ±0.013 (-0.527..-0.501) - [0.0%]

¹ 5184 Games rolled with Variance Reduction.
Dice Seed: 271828
Moves: 3-ply, cube decisions: XG Roller

² 1296 Games rolled with Variance Reduction.
Dice Seed: 271828
Moves: 3-ply, cube decisions: XG Roller

eXtreme Gammon Version: 2.19.211.pre-release

-------
Variant
-------

XGID=--b-B-E-C-A-bB---bbdc-A-A-:0:0:1:61:0:0:0:0:10

Score is X:0 O:0. Unlimited Game
+13-14-15-16-17-18------19-20-21-22-23-24-+
| X O O | | O O X X |
| X O O | | O O |
| | | O O |
| | | O |
| | | |
| |BAR| |
| | | X |
| | | X |
| X | | X |
| O X | | X X O |
| O X X | | X X O |
+12-11-10--9--8--7-------6--5--4--3--2--1-+
Pip count X: 144 O: 141 X-O: 0-0
Cube: 1
X to play 61

1. Rollout¹ 22/15 eq:-0.449
Player: 40.46% (G:10.95% B:0.56%)
Opponent: 59.54% (G:23.49% B:1.09%)
Confidence: ±0.007 (-0.457..-0.442) - [100.0%]

2. Rollout¹ 24/23 22/16 eq:-0.473 (-0.024)
Player: 39.61% (G:10.96% B:0.54%)
Opponent: 60.39% (G:24.00% B:1.15%)
Confidence: ±0.007 (-0.480..-0.466) - [0.0%]

3. Rollout¹ 22/16 6/5 eq:-0.483 (-0.034)
Player: 40.10% (G:11.90% B:0.73%)
Opponent: 59.90% (G:29.11% B:2.73%)
Confidence: ±0.008 (-0.491..-0.475) - [0.0%]

4. Rollout¹ 13/7 8/7 eq:-0.494 (-0.045)
Player: 39.73% (G:11.42% B:0.65%)
Opponent: 60.27% (G:25.68% B:2.19%)
Confidence: ±0.007 (-0.502..-0.487) - [0.0%]

5. Rollout¹ 22/16 10/9 eq:-0.544 (-0.095)
Player: 38.15% (G:10.41% B:0.52%)
Opponent: 61.85% (G:24.68% B:1.32%)
Confidence: ±0.007 (-0.551..-0.537) - [0.0%]

¹ 5184 Games rolled with Variance Reduction.
Dice Seed: 271828
Moves: 3-ply, cube decisions: XG Roller

eXtreme Gammon Version: 2.19.211.pre-release

---
Tim Chow

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