MK, I'm absolutely not a spokesperson for the group. I'm merely an enthusiastic
user who tries to take some the load off the devs by answering those questions
that I'm able to. If they are not commenting, it's for their own reasons and
that shouldn't be interpreted as a tacit endorsement of my opinions.
MK: 1) You acknowledged that the bot becomes inadequate against even a most
primitive mutant cube strategy, (hopefully we will discuss my more elaborate
ones later also), and is obligated to adjust its "cube skill theory",
The gnubg cube strategy assumes that the other player plays like gnubg. I
suggested a strategy that I thought could better if it was known that the
opponent was always taking. Ways to improve results when playing against humans
as opposed bot v. bot move arises frequently in bg discussions.
MK: 2) You switched to a strategy of minimizing your losings instead of
maximizing your winnings, which is the exact opposite of what the "cube skill
theory" is supposed to promote
I don't know how you conclude that. I consider improving net points difference,
be that + or -. Nor have I considered whether my strategy would be optimal. My
answer to why I "wouldn't double at 99%" is indeed about minimizing losses, but
it's in the context of maximising net points won. The only reasons to double
"now" rather than wait a turn is that (a) your position might improve to a
point where they will drop the cube and you only win one point - you "lose your
market" (b) the game might end before your next turn, so you only win one point
(c) the game might go badly, and you regret doubling.
My strategy was to maximise the points won through a & b, and to minimise the
points lost at c. Crudely speaking:
a) doesn’t apply if your opponent will never drop the cube
b) if you are >50% and <= 4 crossovers left so doubles could end the game, cube
(This is an oversimplification to illustrate the concept)
c) minimise the losses on the 1% of games that go badly. Given condition a, it
is always correct to wait a turn because your opponent will still take. You can
never lose your market.
MK: After 1,000 games mutant won 1,411 points (56.66%) vs bot's 1,079... there
was almost no fluctuation with the cube never going past 2, with the mutant
almost always reaching GWC > 50% and doubling early in the game and your bot
never doubling at GWC < 100%, at which the mutant dropped. There were also a
few 1-point wins.
My strategy was not to double until 100%, on the understanding that your
strategy would always take (which also means that it would never be Too Good to
Double). But since your bot WAS dropping when win chances were 100%, then mine
was always losing its market. Your experiment demonstrates the importance of
doubling before you lose your market.
-Original Message-
From: Murat K
Sent: Wednesday, April 10, 2024 7:51 AM
To: bug-gnubg@gnu.org; Ian Shaw
Subject: Mutant cube skills; Two birds in the bush better than one in the hand?
Hi Ian,
On the one hand, since nobody else in this forum negates, nor even adds
anything to support your arguments, I feel that I'm debating with a
spokesperson for the group, but on the other hand I feel that our ideas don't
attain their full potential.
With this thread having become too long and more about mutant cube strategies
than value of cube ownership, I will take the opportunity to start a new thread
responding to your last post, not only here in bug-gnubg but also in
rec.games.backgammon and bgonline.org forums where you had posted in the past,
for the sake of creating more interest on the subject and hoping that you will
participate in those forums also.
> -
> *From:* MK
> *Sent:* Wednesday, April 3, 2024 10:29:11 pm > *To:* Ian Shaw
> ; GnuBg Bug > *Subject:* Re:
> Interesting question/experiment about value of cube ownership > > On
> 4/2/2024 7:08 AM, Ian Shaw wrote:
>
>> A cube strategy against a bot that never passes:
>
> Not never but we loosely say that since it takes at GWC > 0, > i.e. even at
> 0.0001% > >> only double when (a) you are 100% to win > > I don't
> understand why you wouldn't double at 99%? Can you > explain this?
>
>> (b) it's the last roll of the game and you have an advantage.
>
> Yes, this is very bad for the mutant and already happens now.
>
>> So the take point is 16.7%. Gammons complicate it, but I'm >> sure you get
>> the idea.
>
> If you can clearly define your strategy, I would be glad to > create a
> script to run the experiment to see what will happen.
>
> BTW: you are still avoiding the issue of how much the mutant > will win
> compared to what it would be expected to win based on > its total "cube
> error rate".
>
> What win rate would you say a mutant that takes at GWC > 0.0001 > even on
> the last roll, (which must be the biggest possible cube > error), will
> achieve? Any
