On Sun, 8 Dec 2019 at 10:15, Timothy Y. Chow <[email protected]> wrote:
> On Sun, 8 Dec 2019, Joseph Heled wrote: > > Of course you need to weight every position with the probability it > > occurs in actual play. > > You say "of course," but I don't agree. Weighting things in that way > amounts to demanding perfection only from the starting position. In my > book, perfection means perfection from any legal position. This is > sometimes referred to as "strongly solving" a game as opposed to "weakly > solving" or simply "solving" it. > Agreed, but from a practical point of view, not caring about non-reachable positions and positions with a very low probability is good enough for a playing-bot. And again, from a practical point of view, not redoubling past (say) 64 is a reasonable tactic for a playing-bot (unless in a race). (said by someone who is 1500 player in money games. also, the requirements from a "playing-bot" might be very different than the ones from an "analyzing bot") -Joseph > > I don't think 2009 threads are a good indication. We need something with > > the current net, which I think is better. > > This is fair. I would guess that GNU 2-ply (version 1.xx) and XG 3-ply > (version 2.xx) are still susceptible to the tactic, though less so than > earlier versions. But this is just speculation; the only way to find out > is for someone experienced with the relevant tactics to try it out. > > I think that XG won't let you turn the cube past 1024 in actual play, so > that might be an obstacle. What typically happens in a money session is > that the human loses a long string of games and then makes up for it in a > favorable game, when the bot will beaver and redouble when it is losing. > If you can get the bot to do this a few times in a row then you can win > thousands of points in a single game. If your goal is simply to come out > ahead at the end of the session, then you might need to win just one such > super-favorable game, since then you can protect your lead by dropping all > doubles in all subsequent games, and refusing to double yourself until > you're sure it's a drop. > > Of course any computer is going to have *some* limit on the cube but I > doubt that a cap of 2^30 or even 2^20 will be a serious limitation. > > Tim > >
