A recent PRgammon discussion in bgonline, (see:
https://www.bgonline.org/forums/webbbs_config.pl?read=219985), nudged me to post on a subject that
has been on my mind for many years.
In how the strengths of bots have been compared, by only looking at the positions they play
differently and letting one of the bots (the one already assumed to be stronger) decide which is a
better play, I see the same problem with PRgammon.
This approach totally ignores that, if played out, the rest of the game will enfold differently
after that point on. If a play is the better play because it results in more wins and if GNUBG ends
up winning the game after its "inferior play" (according to XG) then it will have made the better
play indeed.
I play against both bots and over the years I observed that I do visibly better against XG than
GNUBG. Either GNUBG cheats better than XG ;) or there may be other explanations for it such as that
playing "style" does indeed matter, (as it was mentioned regarding PRgammon).
If we accept that equally strong players can have different styles and if "styles" can define
certain "strategies" of playing the same positions consistently differently, then we have to accept
that there are more than just one best play at least in different types of games, (i.e. backgames)
and also in games between players of different "style vs another style".
With all this, I personally believe that GNUBG is stronger than XG and that this would be proven if
the bots were made to play a large number of actual games and matches, and comparing wins/losses
instead of PR's.
I think this can be done using GNUBG's Python scripting to make decisions/moves for both bots.
Assuming key strokes can be passed to XG to make it play, its before and after position ID's can be
read by GNUBG and its play duplicated. I haven't really looked into this. Has anyone else thought
about this and has any ideas/suggestions on how to go about it? If done, I think the result of such
a comparison can/will be a "game changer".
MK