Re: [Bug-gnubg] I'm a bit confused

[Joern Thyssen]

On Wed, Jul 30, 2003 at 12:57:03PM +0200, Jim Segrave wrote
> On Wed 30 Jul 2003 (09:30 +0000), Joern Thyssen wrote:
> > When a "double, pass" is encountered the rollout is truncated.
> > 
> > For a trial ending in "game over" the cubeful equity is equal to the
> > cubeless one (e.g., +1, -1, +2, -2, etc), so we add, say, +1 to the
> > cubeful equity. It's the same as normal play: even though the match or
> > sesion is played with a cube, one player is awarded "cubeless" points
> > when the match or game is over -- the value of holding the cube is nil
> > when the game is over.
> > 
> > Of course, for a rollout with variance reduction the cubeful result of,
> > e.g., +1 will be corrected with the total luck for that trial.
> 
> 
> OK - now I see why you said you'd considered removing those stats. But
> my next question would be - should the stats for a cubeful rollout
> actually reflect the wins/lose/gammons etc. including cube play?
> 
> > Continuing the rollout has actually suggested by Michael Zehr a long
> > time ago as extra variance reduction. I think the idea is to branch at
> > every "double, pass" or "double, take" decision.
> 
> I just googled and as I read it, he's suggesting branching at
> double/takes, not continuing after double/pass.
> 
> http://www.bkgm.com/rgb/rgb.cgi?view+567

Yes, exactly. 

How does the Zehr-algorithm work? You have the results from the  two
branches. What is it exactly that you add to the cubeful equity?

Jørn