Re: [Bug-gnubg] Re: Rollout settings?? What went wrong?

[Jim Segrave]

On Fri 22 Apr 2005 (12:18 +0200), ?ystein O Johansen wrote:
> I'm posting this to the mailing list just to archive it. It's originally
> posted by Jim to the GammOnLine forum, but GammOnLine is not archived so I
> post it here for the archiving in the mainling list. This message can be
> nice for the documentation.
> 
> -?ystein
> 
> --- 8< --- The message ---8< ---
> 
> If I had to guess, I'd guess that you'd done at least a short rollout of
> this position, then decided to choose different settings to get a more
> accurate rollout. When this happens, gnubg will try to extend the original
> rollout and will use the settings from the original rollout, not the
> current settings. If you want to restart a rollout using different
> settings, use the 0 or 1 play button first to get an ordinary evaluation,
> then starr ot the rollout. Just to be clear, if you want to change any of
> the following, you must ensure that the current evaluation is *NOT* a
> rollout:
> 
> 
> Truncated/not truncated
> 
> 
> Truncation number of moves
> 
> 
> Stepped truncation (changing evaluation parameters after some number of
> moves)
> 
> 
> Cubeful/Cubeless
> 
> 
> Quasi-random dice
> 
> 
> Truncation at bearoff databases
> 
> 
> RNG seed
> 
> 
> Any form of changes of the evaluation settings for either player.
> 
> 
> What isn't a problem when extending a rollout and doesn't require clearing
> the old results:
> 
> 
> Changing the number of trials Changeing the criterion for stopping the
> rollout (e.g. if you previously said to stop if the j.s.d. of the best play
> was 3 or more better than any other, you could change that to 4, or turn it
> off as a stopping parameter and gnubg would "do the right thing"
> 
> 
> The screeenshots and rollout results don't match - grandmaster setting
> disables pruning on 1 ply, and does do 3 ply evaluations, the rollout
> results have 1 ply pruning on andareonly 2 ply evaluations. The most likely
> is that you had the settings listed in the rollout results, started a
> rollout, decided to use a more strict setting, changed to grandmaster and
> restarted the rollout, expecting gnubg to use the new settings.
> 
> 
> --- 8< ---
> 
> 
> Some discussion: Should the rollout compare the current rollout settings to
> the previous rollout settings before extending an rollout?

Yes, it should. Ideally, we'd like the user to be able to see what's
different (or what the original settings were) and choose between
extending and restarting. The choose between is probably not too hard
to code - just compare the relevant rollout context settings - it's
the method for letting the user see what the executed rollout settings
actually were which is hard.


-- 
Jim Segrave           address@hidden