Re: [Bug-gnubg] Huge evaluation difference

[Øystein Schønning-Johansen]

Yes. Really cool. I have earlier seen significant differences between one-sided and two-sided race evaluation, but this is not one of the positions where it is off.

Some years ago, I used the same algorithm to calculate a full two-sided database for 15 checkers on 6 points. I can share it by bittorrent, or the generating code. The data file is 11 GB. 

-Øystein 

On Sun, 24 Mar 2019 15:00 Philippe Michel, <address@hidden> wrote:

On Thu, Mar 21, 2019 at 12:54:18PM +0100, Øystein Schønning-Johansen wrote:

> Cubeless prob. of saving gammon: 0.129424
> 16: 13/12 12/6  -> 0.913103
> 16: 13/12 8/2   -> 0.938736
> 16: 13/12 7/1   -> 0.942557
> 16: 8/7 8/2     -> 0.984595
> 16: 8/7 7/1     -> 0.984930
> 16: 7/6 7/1     -> 0.922614
> 61: 13/7 8/7    -> 0.984416
> 61: 13/7 6/5    -> 0.984048
> 61: 8/2 7/6     -> 0.915246
> 61: 8/2 6/5     -> 0.984322
> 61: 7/1 6/5     -> 0.984760

It looks like the one-sided bearoff database is accurate to at leat 3
digits :-).

> > > >     1. Cubeful 2-ply    13/6                         Eq.: -2.201
> > > >        0.000 0.000 0.000 - 1.000 0.913 0.000
> > > >         2-ply cubeful prune [world class]
> > > >     2. Cubeful 2-ply    8/2 7/6                      Eq.: -2.204
> > (-0.003)
> > > >        0.000 0.000 0.000 - 1.000 0.915 0.000
> > > >         2-ply cubeful prune [world class]
> > > >     3. Cubeful 2-ply    7/6 7/1                      Eq.: -2.213
> > (-0.013)
> > > >        0.000 0.000 0.000 - 1.000 0.923 0.000
> > > >         2-ply cubeful prune [world class]
> > > >     4. Cubeful 2-ply    13/12 8/2                    Eq.: -2.234
> > (-0.034)
> > > >        0.000 0.000 0.000 - 1.000 0.939 0.000
> > > >         2-ply cubeful prune [world class]
> > > >     5. Cubeful 2-ply    13/12 7/1                    Eq.: -2.240
> > (-0.039)
> > > >        0.000 0.000 0.000 - 1.000 0.943 0.000
> > > >         2-ply cubeful prune [world class]
> > > >     6. Cubeful 2-ply    13/7 6/5                     Eq.: -2.294
> > (-0.093)
> > > >        0.000 0.000 0.000 - 1.000 0.984 0.000
> > > >         2-ply cubeful prune [world class]