Re: [computer-go] results of computer olympiad 9x9
Congratulations to Steenvreeter! I looked at the games against MoGo and Crazystone to see what this engine might do. But it is really hard since most moves played by the top programs are quite good. In the second game against CrazyStone it played like a weak MC-program in the opening - playing all moves in the center and allowing Crazystone as white to make two rock solid groups which in my experience should be an easy win for white. But Crazystone then played some slow moves and made a tactical blunder when Crazystone ignored a forcing move by playing a forcing move which Steenvreeter defended against with a third forcing move threatening to kill a group so Crazystone ended up having to reply to two large threats and collapsed. My impression is that Steenvreeter is a MC-program because it sometimes played moves that I find typical of MC-programs, but that it uses some very good tactics and LD reading in the playouts. It played very strong in all tactical situations as far as I could see in a quick overview. Or perhaps it is a hybrid of a strong tactics engine and MC. Just a guess. Will we see Steenvreeter on CGOS soon or has it already played there with a different name? -Magnus ___ computer-go mailing list computer-go@computer-go.org http://www.computer-go.org/mailman/listinfo/computer-go/
Re: [computer-go] results of computer olympiad 9x9
In the second game against CrazyStone it played like a weak MC-program in the opening - playing all moves in the center and allowing Crazystone as white to make two rock solid groups which in my experience should be an easy win for white. But Crazystone then played some slow moves and made a tactical blunder... Hi Magnus (or anyone), I've noticed this tendency (to play too many central moves, going totally for influence, instead of balancing territory and influence) of monte carlo and UCT programs too. Are you able to explain it? (I almost understand it, but not well enough to put it into words :-). Darren ___ computer-go mailing list computer-go@computer-go.org http://www.computer-go.org/mailman/listinfo/computer-go/
Re: [computer-go] results of computer olympiad 9x9
Is it a new engine nobody knows before ? --- Sylvain Gelly [EMAIL PROTECTED] escribió: Hi Magnus, Congratulations to Steenvreeter. __ Preguntá. Respondé. Descubrí. Todo lo que querías saber, y lo que ni imaginabas, está en Yahoo! Respuestas (Beta). ¡Probalo ya! http://www.yahoo.com.ar/respuestas ___ computer-go mailing list computer-go@computer-go.org http://www.computer-go.org/mailman/listinfo/computer-go/
[computer-go] ICGA 2007 MoGo-Steenvreter
The game: http://www.grappa.univ-lille3.fr/icga/round.php?tournament=169round=9id=2 Sylvain posted some anaylsis from MoGo side. Following are my comments (KGS 4k) as I understand the situation: After white (mogo) H2, MoGo was estimating 74%, and expecting: H2 G1 H3 B1 A1 B3 H1 F8 B5 H4 This is far too optimistic. Why would black play H2? :-) Black played H3, and estimation increased to 81%, white B3 and expecting: B3 B1 A1 B4 C5 C4 A3 C6 B6 B5 After B3 B1 A1, black G1 and then B1 F1 D1 B4 and white is dead. Actually during pondering MoGo realized that it was lost then, because black played the expected move (B1), but the estimation was then 50%. MoGo realized too. Actually G1 is an interesting move. After white 48, all groups on the board is alive and white actually wins by my counting. So I think that white 50 is a losing move. However I wonder where was the mistake: H2, B3 or much before, i.e. already before H2 white was dead? I can't comment on this. Can someone? I think 6 moves before H2, white would have been better playing G2 before B2, but white wasn't losing even till the end as far as I can tell. -- Seo Sanghyeon ___ computer-go mailing list computer-go@computer-go.org http://www.computer-go.org/mailman/listinfo/computer-go/
Re: [computer-go] ICGA 2007 MoGo-Steenvreter
Hello Sanghyeon, thank you for your comments. After white (mogo) H2, MoGo was estimating 74%, and expecting: H2 G1 H3 B1 A1 B3 H1 F8 B5 H4 This is far too optimistic. Why would black play H2? :-) Sorry, white played H2. The sequence I gave starts with white move :). Black was expecting to play G1 :). Black played H3, and estimation increased to 81%, white B3 and expecting: B3 B1 A1 B4 C5 C4 A3 C6 B6 B5 After B3 B1 A1, black G1 and then B1 F1 D1 B4 and white is dead. Ok thanks. So good white actually played G1 instead of A1 after black B1 then. Actually during pondering MoGo realized that it was lost then, because black played the expected move (B1), but the estimation was then 50%. MoGo realized too. Actually G1 is an interesting move. After white 48, all groups on the board is alive and white actually wins by my counting. So I think that white 50 is a losing move. Oh, so contrary to what I believed, you say (if I understand you correctly) that the mistake was done in the upper left group and not in the bottom center group? Thank you, Sylvain ___ computer-go mailing list computer-go@computer-go.org http://www.computer-go.org/mailman/listinfo/computer-go/
Re: [computer-go] ICGA 2007 MoGo-Steenvreter
The game: http://www.grappa.univ-lille3.fr/icga/round.php?tournament=169round=9id=2 Sylvain posted some anaylsis from MoGo side. Following are my comments (KGS 4k) as I understand the situation: After white (mogo) H2, MoGo was estimating 74%, and expecting: H2 G1 H3 B1 A1 B3 H1 F8 B5 H4 This is far too optimistic. Why would black play H2? :-) I think that should have read, Why would black play G1?!. Beyond that, the only thing I've concluded so far (this *is* a complex position) is that white H2 was the only choice at that point. White seems to die quickly in the alternative moves I looked at (G1, H3, B3), and the white chain in the middle is too big to sacrifice. However I wonder where was the mistake: H2, B3 or much before, i.e. already before H2 white was dead? I prefer white 30 at G2 instead of C1, which seems to go well for white. (if black H3-ish then white C1; if black C1 then white G4; did I miss something?) Darren ___ computer-go mailing list computer-go@computer-go.org http://www.computer-go.org/mailman/listinfo/computer-go/
Re: [computer-go] results of computer olympiad 9x9
2007/6/14, Sylvain Gelly [EMAIL PROTECTED]: Thank you for your analysis. Did you looked at the first game Steenvreeter-MoGo (MoGo was white)? I wonder, because MoGo was really happy, estimation always increased, up to 81%, then in one move dropped to less 50%, and MoGo eventually lost. I wonder if MoGo did a blunder, or simply that it evaluated badly the position for some reason. IMO it didn't blunder till move 50, but evaluation drop seems to be caused by too optimistiv evaluation before the drop. -- Seo Sanghyeon ___ computer-go mailing list computer-go@computer-go.org http://www.computer-go.org/mailman/listinfo/computer-go/
Re: [computer-go] results of computer olympiad 9x9
Quoting Sanghyeon Seo [EMAIL PROTECTED]: 2007/6/14, Magnus Persson [EMAIL PROTECTED]: Quoting Sylvain Gelly [EMAIL PROTECTED]: Hi Darren, After white (mogo) H2, MoGo was estimating 74%, and expecting: H2 G1 H3 B1 A1 B3 H1 F8 B5 H4 Then black played H3, and estimation increased to 81%, white B3 and expecting: B3 B1 A1 B4 C5 C4 A3 C6 B6 B5 This sequence is a disaster for Mogo because the position after B5 is trivially lost. Agreed. But the error is white A3 in this variation. Normally making an eye is good in the semeai, and in random playouts it is a winning move in this position. But here it gives black time to win the semeai against the stones which are not protected by the eye. B3 B1 A1 B4 C5 C4 B5 instead captures the black stones right away if I am not blind to something. [Valkyria wants to play C6 instead of C5 which also seems to win easily] This is correct, but the error in the line is black B4. Black would approach from G1 and black wins the semeai. You are right so after B1 (which black must play to make G1 work) then G1 is the only move. Still the fight turns to the upper side after white lives and now white has a chance to live but plays A7 at move 50, but if white plays C9 for life it is very close, but if my analysis is correct then black wins with 0.5 after threatening a seki in the corner. [Valkyria misunderstands this position completely because of the seki in the corner so I could not use it.] Agreed about move 50 at C9, but can black win after that? I guess threatening seki means A8 after C9, then: (first move white, move 50) C9 A8 A7 F9 E9 A6 B8 C6 A9 is forced. Then J3 J2 H4 finishes the game, and B1 A4 D1 A2 are dame. This is a half point win for white. Did I miss something? This is fun! GoGui thinks that black wins 0.5 with chinese rules and 0.5 with Japanese rules! So what rules was the tournament played with and what rules did the programs implement... or am I confused? I have to admit that I am unaware on under which circumstances the rule sets differ. Mogo fills in its own liberties in order to kill the group of Steenvreter, but dies and loose the semeai. It is possible for Mogo to live by throwing in with A9 but then Black will win with a kofight which involves white trying to invade the upper right group as kothreats. This fight was a matter of a single liberty as well... I don't understand this part. After black E9 white throws in A9 and A8 C9 lets white unconditionally alive. However in my counting this is a half point loss for white. Agree. Note that I also wrote it was a half point win for black so you might have mixed up the colors of what I wrote or what you did write. From what you wrote I think we have the same conclusion. But I am not 100% sure of this last analysis on my part, but on the other hand normally MoGo should find a 0.5 win easily at this stage. Minor remark: I was wrong about the final kofight since black can simply skip by decending at J3 as you did above which normally is a bad move. -- Seo Sanghyeon ___ computer-go mailing list computer-go@computer-go.org http://www.computer-go.org/mailman/listinfo/computer-go/ -- Magnus Persson Berlin, Germany ___ computer-go mailing list computer-go@computer-go.org http://www.computer-go.org/mailman/listinfo/computer-go/
[computer-go] results of computer olympiad 9x9
Quoting Magnus Persson: Quoting Sylvain Gelly sylvain.gelly at m4x.org: Hi Darren, After white (mogo) H2, MoGo was estimating 74%, and expecting: H2 G1 H3 B1 A1 B3 H1 F8 B5 H4 Then black played H3, and estimation increased to 81%, white B3 and expecting: B3 B1 A1 B4 C5 C4 A3 C6 B6 B5 This sequence is a disaster for Mogo because the position after B5 is trivially lost. What about white A5? ___ computer-go mailing list computer-go@computer-go.org http://www.computer-go.org/mailman/listinfo/computer-go/
Re: [computer-go] ICGA 2007 MoGo-Steenvreter
So I think that white 50 is a losing move. I have another opinion. After 50, F9 A6 A5 C6 B5 D1 C9 B1 E9 A2 D8 A4 C9 C4 Sil ___ computer-go mailing list computer-go@computer-go.org http://www.computer-go.org/mailman/listinfo/computer-go/
