Re: [Bug-gnubg] Re: Confidence intervals from rollouts

[Joern Thyssen]

On Thu, Sep 05, 2002 at 06:38:00PM +1200, address@hidden wrote
> David Montgomery writes: 
> 
> >
> >>Could you elaboreate on what "ensuring duplicate dice
> >>for subsequent ply" means?
> >
> >Each game is associated with an unlimited stream
> >or sequence of rolls, like this: 
> >
> >Game 1: 21 32 66 43 54 51 51 ...
> >Game 2: 43 22 55 31 42 63 65 ...
> 
> Wonderful! exactly what I did with sagnu and fibs2html, and exactly for the 
> same reason. (but only recently) 
> 
> I was not aware you hit upon this a long time ago :)
> Must be a good idea if (Convergent) evolution finds it twice ... 

Actually thrice :-)

Gary's rollout code from rollout.c has:

  for( i = 0; i < cGames; i++ ) {
     if( prc->rngRollout != RNG_MANUAL )
        InitRNGSeed( rcRollout.nSeed + ( i << 8 ), prc->rngRollout );

Since gnubg doesn't change the seed between rollouts of different moves
the same dice sequence will be used for each game.

Jørn

-- 
Joern Thyssen, PhD
Vendsysselgade 3, 3., DK-9000 Aalborg, Denmark
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