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Past and present of the zero equity before opening roll fallacy.

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MK

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Dec 27, 2022, 7:06:46 AM12/27/22
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Being puzzled by the inability of all the bozos here to
understand that the equity before the opening roll can
be non-zero, I just couldn't stop thinking about it.

I remember that equity gained by winning the opening
roll had been talked about many times in RGB, including
by me, but never regarding how the bots calculated it.

For example, I had given this link in a different context:

https://bkgm.com/openings/rollouts.html

In my this post:

https://groups.google.com/g/rec.games.backgammon/c/k61QtBwlsBk/m/SP86Am44DQAJ

In the introduction section, the undated article says:

"The rollouts on this page where performed using
"Gnu Backgammon, version 0.14, which is the latest
"and strongest version of Gnu BG as of early 2006.
"The rollouts were performed using 2-ply play.....
"Rollouts were performed using cubeless money play.

And in the summary section at the end, its says:

"Here are all the opening rolls ranked from best to
"worst. The best roll is 31 with an equity of +.1670.
"The worst roll is 41 with an equity of +.0024. Your
"average equity if you win the opening roll is +.0393.

All of you bozos here, read that last line very slowly so
that you may understand what it says!

According to Gnubg's Temperature Map, the best roll
is 31 with an equity of +0.218 and the worst roll is 41
with an equity of -0.006 (at the same 2-ply) and the
average equity if you win the opening roll is +0.0543
(excluding doubles).

According to XG's Dice Distribution, the best roll is 31
with an equity of +0.234 and the worst roll is 41 with
an equity of -0.005 (at 1-ply) and the average equity if
you win the opening roll is +0.0547 (excluding doubles).

Then I became curious about how "the fallacy of zero
equity before the opening roll" came about.

I wondered how Snowie calculated the opening roll
equities.

According to its Dice Panel, the best roll is 31 with an
equity of +0.161 and the worst roll is 41 with an equity
of -0.000, and the average equity (Snowie calls "initial
equity") if you win the opening roll is +0.073 including
doubles (but should be +0.0358 excluding doubles).

A quick search using the keywords "Snowie Dice Panel"
struck gold within minutes. Snowie was subtracting the
"initial equity" from the opening roll correctly but was
subtracting the wrong amount +0.073 including doubles.

When people discovered it, they correctly called it a bug
but suggested the wrong correction. For example, see:

https://groups.google.com/g/rec.games.backgammon/c/QwgEfduYVAs/m/dzL6A3cVKTAJ

https://groups.google.com/g/rec.games.backgammon/c/1eSH9FHvQ9Q/m/PXggrEP29D8J

There you have the venerable David Montgomery of
the gamblegammon world, saying:

"Since your equity was 0 before the game started,
"the luck calculation should be based on this .154.
"Snowie instead compares your potential equity
"with the 31 (+.154) to the equity with you on roll
"in the opening position -- including doubles --
"which Snowie estimates as +.072.

Apparently intelligent people can also be stupid! :(

"Before the game starts' is not the same as "before
the opening roll" is rolled!

The game start with determining which player will
roll first, (by whatever ways in different flavors of
backgammon). Once a player "wins the opening roll",
that player's equity is already the "initial", "average",
etc. equity that he will gain after rolling the first roll!

Because in the westernized way of deciding who wins
the opening roll is simultaneous with rolling it, it looks
like all the gamblegammon bozos are confused by that.

This is also why even the brightest of gamblegammon
giants assumed that recycling to the opening position
would take at least 5 rolls. See:

https://www.bkgm.com/rgb/rgb.cgi?view+68

My 4 rolls solution may seem illegal to those people
who can't think for themselves, but there is nothing
to prevent recycling to the opening position more
than once, or twice, or ten times... Thus, not only in
traditional backgammon that the opening position
can be recycled to in 4 rolls, but in gamblegammon
also after the first iteration.

The reason I'm dwelling on this is because a bot or
human with an assuming mind will see the "opening
position" as only just that, and not as any position
that can occur and reoccur after the first roll in a
game. This is very important!

Unless a peson is capable of unbiased/independent
thinking, no amount of reading books, paid lessons,
etc. will help; not even having a PHD in arithmetics,
mathematics, computer programming, etc... :(

I can't know if Montgomery was *the one" and/or
*the only one* who started this fallacy but it seems
like bots like Gnubg and its sibling XG that followed
Snowie, have implemented this fallacy by throwing
out the baby with the bath water... :(

This is a perfect example of how people who acquire
an undeserved credibility can lead the flock of sheep
in the wrong direction, all the way, for a long time...

Now, let's see how long it will take for those same
"mis-intelligent" shepherds to admit their mistakes,
and for the bots to start calculating opening luck
rates correctly...??

MK

Timothy Chow

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Dec 29, 2022, 9:41:41 PM12/29/22
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On 12/27/2022 7:06 AM, MK wrote:
> Because in the westernized way of deciding who wins
> the opening roll is simultaneous with rolling it, it looks
> like all the gamblegammon bozos are confused by that.

Not at all. It's just that the luck of *deciding who
wins the opening roll* is included in GNU's luck calculation.

Leaving out this luck from the calculation would just result
in confusion.

---
Tim Chow

Nasti Chestikov

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Dec 30, 2022, 12:41:53 PM12/30/22
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On Friday, 30 December 2022 at 02:41:41 UTC, Tim Chow wrote:

> Not at all. It's just that the luck of *deciding who
> wins the opening roll* is included in GNU's luck calculation.
>
> Leaving out this luck from the calculation would just result
> in confusion.
>
> ---
> Tim Chow

So getting an opening roll of 4-1 trumps the bots response of 6-6?

You seem like an educated individual, you *surely* must know that you're posting bollocks?

In deference to Murat, I won't refer my previous posts to you hawking fast cars around the Las Vegas strip.......but try to stay focused in this newsgroup FFS?


MK

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Dec 31, 2022, 6:28:01 AM12/31/22
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I have explained and illustrated in painful detail
that the opening position has an average equity
(which is attached to it) like any other position,
regardless of when it occurs during a game.

I thought you had understood and agreed that if
you decide who will go first by a coin toss, that
player becomes the "player on roll" at that position
that has a "position ID" just like any other position.

That "position ID" is the same whether it happens
to occur as the first position or the 6th position in
a game, regardless of what we may call them, (i.e.
"opening position", "recycled opening position", etc.)

"Opening roll" is different than "opening position".
Even at the beginning of a game the "opening roll"
happens after the "opening position". When the
"opening position" occurs again in a game after
recycing, there is no "opening roll" associated with
it anymore but just a regular roll just like any other
roll at any other stage of the game.

This is my last effort on this subject. If you still can't
understand this, I must conclude that you don't have
enough brains for it and I will move on... :(

MK

Timothy Chow

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Dec 31, 2022, 10:13:49 AM12/31/22
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> recycing, there is no "opening roll" associated with
> it anymore but just a regular roll just like any other
> roll at any other stage of the game.

Everything you say here is correct.

None of it implies that one should subtract 0.0543 from the luck
in the way you have suggested.

---
Tim Chow

Timothy Chow

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Dec 31, 2022, 10:15:10 AM12/31/22
to
On 12/30/2022 12:41 PM, Nasti Chestikov wrote:

> So getting an opening roll of 4-1 trumps the bots response of 6-6?
>
> You seem like an educated individual, you *surely* must know that you're posting bollocks?
>
> In deference to Murat, I won't refer my previous posts to you hawking fast cars around the Las Vegas strip.......but try to stay focused in this newsgroup FFS?

Certainly! As soon as you tell me where you went to law school.

---
Tim Chow


Nasti Chestikov

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Dec 31, 2022, 12:26:53 PM12/31/22
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On Saturday, 31 December 2022 at 15:15:10 UTC, Tim Chow wrote:

> Certainly! As soon as you tell me where you went to law school.
>
> Tim Chow


Here you go:

https://www.law.ac.uk/

Now, will you behave?

Or at least focus on the issues presented to you. Or at least pretend to focus on the issues presented to you.

It isn't difficult, all I'm asking is that you function like a normal human being.

Do you think you can do that - in this newsgroup anyway? (I don't care what you get upto with your cars).

Timothy Chow

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Jan 2, 2023, 9:49:59 AM1/2/23
to
On 12/31/2022 12:26 PM, Nasti Chestikov wrote:
> Here you go:
>
> https://www.law.ac.uk/

So surely you know that libel law in the U.K. differs tremendously
from libel law in the U.S.?

> Now, will you behave?
>
> Or at least focus on the issues presented to you. Or at least pretend to focus on the issues presented to you.

Fair enough. We were discussing the luck of the opening roll. So
your comment about the second roll is a complete non sequitur. Even
Murat knows this.

---
Tim Chow

MK

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Jan 2, 2023, 8:49:56 PM1/2/23
to
On January 2, 2023 at 7:49:59 AM UTC-7, Tim Chow wrote:

> On 12/31/2022 12:26 PM, Nasti Chestikov wrote:

>> Here you go:
>> https://www.law.ac.uk/

> So surely you know that libel law in the U.K.
> differs tremendously from libel law in the U.S.?

Children! Dalai Lama is about to lose his
patience with you... :( He will spank you if
you don't fuck off to play somehwere else.

MK
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