The decision I was faced with below appears a consequential choice,
which requires considerable thought.
3/off minimizes shots. However, by not hitting the opponent, we
gain fewer pips.
I chose 3/off but the bot's analysis (I'm not sure a rollout is necessary)
says that the two plausible plays are of exactly equal merit.
Naively, I would think that, at gammon go, we hit. However, the
analysis doesn't bear that out. In fact hitting seems clearly wrong
at 2A/1A Crawford because we don't get any benefit from the backgammons
and the backgammons are the upside of hitting.
The reason hitting isn't gammonish is that the opponent can also
save a gammon by hitting back and hitting gives approx 5.6% more returns.

Paul

XGID=-CaB---------------cbcbbb-:1:-X:Daniel O:eXtremeGammon
1:1:21:0:2:3:0:10

Score is X:0 O:2. Unlimited Game, Jacoby Beaver
+13-14-15-16-17-18------19-20-21-22-23-24-+
| | | O O O O O O | +---+
| | | O O O O O O | | 2 |
| | | O O | +---+
| | | |
| | | |
| |BAR| |
| | | |
| | | |
| | | X |
| | | X X |
| | | X O X |
+12-11-10--9--8--7-------6--5--4--3--2--1-+
Pip count X: 9 O: 75 X-O: 0-2
Cube: 2, O own cube
X to play 21

1. 4-ply 3/Off eq:+1.345
Player: 92.88% (G:51.29% B:0.00%)
Opponent: 7.12% (G:0.00% B:0.00%)

2. 4-ply 3/2* 2/Off eq:+1.345
Player: 91.59% (G:51.29% B:2.99%)
Opponent: 8.41% (G:0.00% B:0.00%)

3. 2-ply 3/1 3/2* eq:+1.090 (-0.255)
Player: 90.41% (G:31.31% B:0.25%)
Opponent: 9.59% (G:0.00% B:0.00%)


eXtreme Gammon Version: 2.10

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

On Monday, November 15, 2021 at 7:36:48 PM UTC, peps...@gmail.com wrote:

The decision I was faced with below appears a consequential choice,
which requires considerable thought.
3/off minimizes shots. However, by not hitting the opponent, we
gain fewer pips.
I chose 3/off but the bot's analysis (I'm not sure a rollout is necessary) says that the two plausible plays are of exactly equal merit.
Naively, I would think that, at gammon go, we hit. However, the
analysis doesn't bear that out. In fact hitting seems clearly wrong
at 2A/1A Crawford because we don't get any benefit from the backgammons
and the backgammons are the upside of hitting.
The reason hitting isn't gammonish is that the opponent can also
save a gammon by hitting back and hitting gives approx 5.6% more returns.

Paul

XGID=-CaB---------------cbcbbb-:1:-X:Daniel O:eXtremeGammon
1:1:21:0:2:3:0:10

Score is X:0 O:2. Unlimited Game, Jacoby Beaver +13-14-15-16-17-18------19-20-21-22-23-24-+
| | | O O O O O O | +---+
| | | O O O O O O | | 2 |
| | | O O | +---+
| | | |
| | | |
| |BAR| |
| | | |
| | | |
| | | X |
| | | X X |
| | | X O X |
+12-11-10--9--8--7-------6--5--4--3--2--1-+
Pip count X: 9 O: 75 X-O: 0-2
Cube: 2, O own cube
X to play 21

1. 4-ply 3/Off eq:+1.345
Player: 92.88% (G:51.29% B:0.00%)
Opponent: 7.12% (G:0.00% B:0.00%)

2. 4-ply 3/2* 2/Off eq:+1.345
Player: 91.59% (G:51.29% B:2.99%)
Opponent: 8.41% (G:0.00% B:0.00%)

3. 2-ply 3/1 3/2* eq:+1.090 (-0.255)
Player: 90.41% (G:31.31% B:0.25%)
Opponent: 9.59% (G:0.00% B:0.00%)

eXtreme Gammon Version: 2.10

Oops. I misread (or misanalysed) the table.
At Gammon Go, we do indeed hit.
The 2.99% extra backgammons become match-winning gammons.
At this score it's an excellent trade off to get 3% more gammons at the price of 1.3% more losses.

Paul

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

On 11/15/2021 2:41 PM, peps...@gmail.com wrote:

Oops. I misread (or misanalysed) the table.
At Gammon Go, we do indeed hit.
The 2.99% extra backgammons become match-winning gammons.

No, you got it right the first time.

The first reported pseudocubeless number includes single
wins, gammons, and backgammons.

The pseudocubeless number marked "G" includes both gammons
and backgammons. You can verify this by setting up a position
where the gammon is certain but the backgammon is not. You
will see that the "G" number is 100%.

---
Tim Chow

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

On 11/15/2021 2:36 PM, peps...@gmail.com wrote:

XGID=-CaB---------------cbcbbb-:1:-X:Daniel O:eXtremeGammon 1:1:21:0:2:3:0:10

This is perhaps your most interesting garble to date.

---
Tim Chow

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

On Tuesday, November 16, 2021 at 3:30:37 AM UTC, Tim Chow wrote:

On 11/15/2021 2:36 PM, peps...@gmail.com wrote:

XGID=-CaB---------------cbcbbb-:1:-X:Daniel O:eXtremeGammon 1:1:21:0:2:3:0:10

This is perhaps your most interesting garble to date.

---
Tim Chow

Sorry about that.
Are you able to reconstruct the position anyway?

Paul

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

On 11/16/2021 7:00 AM, peps...@gmail.com wrote:

On Tuesday, November 16, 2021 at 3:30:37 AM UTC, Tim Chow wrote:

On 11/15/2021 2:36 PM, peps...@gmail.com wrote:

XGID=-CaB---------------cbcbbb-:1:-X:Daniel O:eXtremeGammon
1:1:21:0:2:3:0:10

This is perhaps your most interesting garble to date.

---
Tim Chow

Sorry about that.
Are you able to reconstruct the position anyway?

Yes, I entered the position manually, checker by checker.

---
Tim Chow

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

On Tuesday, November 16, 2021 at 1:56:23 PM UTC, Tim Chow wrote:

On 11/16/2021 7:00 AM, peps...@gmail.com wrote:

On Tuesday, November 16, 2021 at 3:30:37 AM UTC, Tim Chow wrote:

On 11/15/2021 2:36 PM, peps...@gmail.com wrote:

XGID=-CaB---------------cbcbbb-:1:-X:Daniel O:eXtremeGammon
1:1:21:0:2:3:0:10

This is perhaps your most interesting garble to date.

---
Tim Chow

Sorry about that.
Are you able to reconstruct the position anyway?

Yes, I entered the position manually, checker by checker.

It shows another example of how the luck factor operates in backgammon.
If all the non-beginner plays have the same equity, then among non-beginners, there's no
advantage in understanding the position (with regard to that particular play at least).

Paul

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