RE: [Bug-gnubg] Hint on cube decisions

[Ian Shaw]

 From: Kari Uusitalo Sent: 16 June 2006 11:38

> I am playing around with the GNU BG and tried to find info 
> about what excatly different lines mean in hint ouputs ofr 
> cube selection.
> 
> For example, I have the cube in a certain game situation and 
> the hint returns:
> 
> >>>>>>>>
> Cube analysis
> 2-ply cubeless equity  -0.039
>   0.479 0.108 0.002 - 0.521 0.105 0.002
> Cubeful equities:
> 1. No double            +0.124
> 2. Double, pass         +1.000  ( +0.876)
> 3. Double, take         -0.433  ( -0.556)
> Proper cube action: No redouble, beaver (38.8%)
> >>>>>>>>
> 
> What exactly the different lines mean. I guess, the last line 
> is the most important and in this case I should not double. 
> What does the "beaver"-text in that particular line mean and 
> what does the percentage figure stand for?

When an opponent doubles, some games allow to to Beaver. E.g. If Player
A doubles to 2, Player B can Beaver to 4 - keeping the cube on his side.

Roughly speaking, you should beaver if your opponent has doubled you
when you are the favourite to win, as in the example above. The opponent
is expected to win 52.1% of the games, so gnubg recommends that you
don't double, but if you do, then the opponent should beaver.


The 38.8% figure means that the double would be correct if 38.8% of
opponents were to mistakenly pass the double.

I hope this helps.

-- Ian Shaw