I just watched this Zen19N game: http://files.gokgs.com/games/2010/8/30/Zen19N-atheist.sgf
If I am reading correctly, Zen could have killed the bottom right, but played its own liberties before taking away its opponent's liberties. There is also a tail which zen lost at the top, due to negligence. The bottom left group, I think, could have been saved. This looks like a classic case of snatching defeat from the jaws of certain victory. Perhaps this game can provide some useful test cases? Terry McIntyre <[email protected]> Unix/Linux Systems Administration Taking time to do it right saves having to do it twice. ----- Original Message ---- > From: Yamato <[email protected]> > To: [email protected] > Sent: Thu, August 26, 2010 9:33:16 AM > Subject: Re: [Computer-go] Last night: Zen5.8 vs John Tromp > > I attach the image of Zen's evaluation in the game. > > Look at the white groups at the top and top-left. Both of them are not > 100% correctly evaluated. When this happens, Zen gets weaker because of > the divergence and inaccuracy of Monte-Carlo simulations. > I think it must be the current major problem of all MC programs. > > > Christian Nentwich wrote: > >From a quick look, I would say the bots' evaluation in this case is entirely > >correct. Zen was quite far ahead, and then made some bad endgame mistakes. > >The trade around move 200 is particularly costly. Playing even a simple safe > >move at 176 (like B10) would win the game without trouble. > > > >Christian > > > > > >On 26 August 2010 10:01, Darren Cook <[email protected]> wrote: > > > >> > Tonight an interesting game was played in the > >> > cellars of KGS: Zen19N vs Tromp. > >> > (Zen is a bot, Tromp is John Tromp...) > >> > > >> > You can download the sgf from the KGS archives at > >> > http://www.gokgs.com/gameArchives.jsp?user=tromp&year=2010&month=8 > >> > > >> > For a long time bots (Zen itself, Many Faces) believed > >> > that White (=Zen) was clearly ahead. But around move 200 > >> > the evaluations swung over, until Tromp won after move 271. > >> > >> Thanks Ingo. What are people's thoughts: were the programs mistaken in > >> their optimism, or did Zen make a mistake in the middle game? > >> > >> Darren > >> > >> > >> -- > >> Darren Cook, Software Researcher/Developer > >> > >> http://dcook.org/gobet/ (Shodan Go Bet - who will win?) > >> http://dcook.org/work/ (About me and my work) > >> http://dcook.org/blogs.html (My blogs and articles) > >> _______________________________________________ > >> Computer-go mailing list > >> [email protected] > >> http://dvandva.org/cgi-bin/mailman/listinfo/computer-go > >> > >---- inline file > >_______________________________________________ > >Computer-go mailing list > >[email protected] > >http://dvandva.org/cgi-bin/mailman/listinfo/computer-go > > -- > Yamato _______________________________________________ Computer-go mailing list [email protected] http://dvandva.org/cgi-bin/mailman/listinfo/computer-go
