Re: [Bug-gnubg] Rollout bugs (j.s.d. options)

[Christopher D. Yep]

At 08:49 AM 7/31/2003 +0200, Jim Segrave wrote:
> On Thu 31 Jul 2003 (00:36 -0400), Christopher D. Yep wrote:
> > Windows version 0.14-devel 1.1227 030727 (build Jul 27 2003)
> >
> > Settings --> Rollouts --> General Settings
> >
> > Suppose I want to rollout 8/5 6/5 and 24/23 13/10 for an opening 3-1.
> >
> > Suppose I check both boxes under "stop rollouts of multiple moves based on
> > j.s.d."
> >
> > (BTW, can anyone explain the intended behavior when one but not both boxes
> > are checked?)
>
> One box says to stop any rolling out any move whose j.s.d. makes it
> not a candidate, but to continue the rollout for at least the best
> move until all the trials are completed.
>
> The other box says to stop the entire rollout as soon as a "best" move
> has been found.

Thanks, makes sense.

> > Set minimum trials to 36 and "No of j.s.d.s from best move to .001"
> >
> > Then set-up the position, press CTRL-H to get a hint window, and select 
> 8/5
> > 6/5 and 24/23 13/10 to rollout.  gnubg should then rollout each 36
> > times.  Actually gnubg rolls out each 37 times (bug #1).
> >
> > Bug #1: If I set minimum trials to N, the actual minimum trials is N+1.
>
> Just to check - do you know when your copy of gnubg was built? I don't
> get this error with the current version.

Windows version 0.14-devel 1.1227 030727 (build Jul 27 2003).  I can 
download a more recent build, but I didn't see any mention of a bug fix 
related to this bug in the ChangeLog since 1.1227.

Also I can visually see that it's doing 37 trials (I watched each number 
change).  For some of the testing I changed the minimum number of trials to 
2 so that it would run even faster (in the latter case it would run 3 
trials of each move).

Here's a sample of the output (copied from the hint window), so it appears 
to be more than just a cosmetic bug in the progress window:

    1. Rollout          8/5 6/5                      Eq.:  +0.142
        53.9%  18.2%   0.4% -  46.1%  11.7%   0.4% CL  +0.142
      [  1.2%   1.0%   0.2% -   1.2%   1.0%   0.1% CL   0.033]
        Full cubeless rollout (trunc. at one-sided bearoff) with var.redn.
        37 games, Mersenne Twister dice gen. with seed 1174625920 and 
quasi-random dice
        Play: 0-ply cubeful
        Cube: 0-ply cubeful
    2. Rollout          24/23 13/10                  Eq.:  -0.068 ( -0.210)
        47.5%  11.4%   0.4% -  52.5%  13.2%   0.5% CL  -0.068
      [  1.3%   1.1%   0.7% -   1.3%   1.0%   0.1% CL   0.035]
        Full cubeless rollout (trunc. at one-sided bearoff) with var.redn.
        37 games, Mersenne Twister dice gen. with seed 1174625920 and 
quasi-random dice
        Play: 0-ply cubeful
        Cube: 0-ply cubeful

> > Also, what is the intended behavior if I check the box under "Stop when
> > result is accurate" as well as both boxes under "stop rollouts of multiple
> > moves based on j.s.d."?  Does it stop the rollout when either condition is
> > satisfied?  Also, what is the minimum number of trials?  The minimum 
> number
> > contained in "stop when result is accurate" or the minimum number 
> contained
> > in "stop rollouts of multiple moves based on j.s.d."?
>
> If either of the j.s.d. options is set, the "stop when result is
> accurate" options are silently turned off for the rollout, so none of
> these settings will take effect. I was going to change things so that
> those options greyed out when the jsd options were active, but I am
> seriously considering simply removing the "stop when result is
> accurate", as it has some real problems for equities or win/lose
> probabilities around 0 (not that it's inaccurate, just that the
> settings make no sense).

Thanks for the explanation.

> > Bug #2: When either box in "stop rollouts of multiple moves based on
> > j.s.d." is checked, if I then select only one move to rollout from the 
> Hint
> > window, gnubg will only do 1 trial.
>
> Current version is a bit better, one of the two options works
> correctly, the other does not. I'll fix this sometime today.

Actually I was mistaken before.

If I check only the first box ("stop rollout when one move appears to be 
the best"), gnubg will do 1 trial.  (This is definitely a bug.)

If I check only the second box ("stop rollout of move when best move j.s.d. 
appears better"), gnubg will rollout as many trials as is specified in the 
Trials box at the very top of the Rollout General Settings window (i.e. 
this is different than the "minimum trials" next to "stop rollout when one 
move appears to be the best").  This seems like it might be a bug, although 
it might be your intended behavior.

> > Minor Bug #3: Even if I don't check any box in "Stop when result is
> > accurate" or "stop rollouts of multiple moves based on j.s.d.", when I
> > click "Ok" gnubg reports that "Rollouts can stop..." and "Rollouts may
> > stop..." when these conditions are met.  (However gnubg correctly ignores
> > these conditions in its rollouts, thus the above is just a "cosmetic" bug.)
>
> As in bug 1, I saw earlier reports of this, but I can't reproduce this
> on the current version (although I never conciously fixed it).

I'll see if it goes away on later versions.  If it doesn't go away, I can 
give you more details on how to reproduce it in a few days or weeks.  This 
is just a cosmetic bug anyway.

Chris