Re: [Computer-go] Seki in playouts
I just tried this, and included code in the playout to save groups in atari by counter-capturing enemy stones. It still chooses to connect in that situation, so I am going back to passing in playouts. On 2015-04-16 3:41, Aja Huang wrote: On Wed, Apr 15, 2015 at 12:24 PM, Igor Polyakov weiqiprogramm...@gmail.com mailto:weiqiprogramm...@gmail.com wrote: 5. But it misses this because squeezing leads to a few accidental losses in playouts where black plays something that white doesn't respond to My two cents: just prevent the accidental losses in playouts then the program will play B8 correctly. Aja ___ Computer-go mailing list Computer-go@computer-go.org http://computer-go.org/mailman/listinfo/computer-go ___ Computer-go mailing list Computer-go@computer-go.org http://computer-go.org/mailman/listinfo/computer-go
Re: [Computer-go] Seki in playouts
2. Have custom seki logic that will just prevent you from playing a nakade shape against a group that already has an eye Aya does this. But eye recognition is only if string lib is 2 and stones =2. If probability from 3x3 pattern is zero, it is eye. And I also have special logic for this shape. Black never suicide except white lib is one. Regards, Hiroshi Yamashita ___ Computer-go mailing list Computer-go@computer-go.org http://computer-go.org/mailman/listinfo/computer-go
Re: [Computer-go] Seki in playouts
Interesting position. I am not sure how I exactly handle this is in Valkyria. My code for allowing or disallowing suicide is very complex. As long as special case-handling is only executed when necessary. In this case the pattern with two stones forming a possible eye would be starting point for special handling of B8. Most important is to correctly handle the simplest cases. That is to prevent suicide as soon as white has an eye and only two liberties. The next step here could be that it is not necessary to plack black B8 if black can prevent white B8, by playing black D9 or D7 for example. But I am not sure if it is possible to make sure that there are situations where this logic is bad. I would then implement the rule, and run simulations for a long time on an empty board and dump every position to a log file where the new rule triggers. If I find situations where the new rule is bad i would then try to fix the rule, or if I think it is impossible or too costly I would just leave it as it is. So, in other words in Valkyria I would try to detect the most clean basic seki variants perfectly. But I would also try to add special cases to the code to improve plays that might not always be correct but in the majority of cases. Valkyria is in principle a huge decision tree where all branches are hand coded. Best Magnus On 2015-04-15 13:24, Igor Polyakov wrote: I have an interesting problem with my program. 1. I have self-atari detection, but self-atari is allowed for smaller groups like the two stone group because it can make a nakade. 2. Self-atari detection means that in most playouts the program will let the black player suicide, but it won't let the white player suicide because the group is too large. 3. Therefore, it has white winning playing D9 or D7 because the playouts have black suicide 4. It has to squeeze right now because the seki loses the game, while the squeeze wins it. 5. But it misses this because squeezing leads to a few accidental losses in playouts where black plays something that white doesn't respond to I have thought about this and there's a few solutions: 1. Allow the program to pass late in playouts. In the current implementation this leads to accidental pass-pass playouts when the game is not finished and the program is poor at evaluating boards with dead stones on them. 1a. Implement a special passing type that doesn't end the game, but only allows you take back ko or just let your opponent finish their game when you still have legal moves left you don't want to take 1b. Make the program good at deciding dead stones somehow and not worry about pass-pass in playouts as long as it's late enough (what's late enough? 75% of the board filled?) 2. Have custom seki logic that will just prevent you from playing a nakade shape against a group that already has an eye I noticed that every program does this correctly that I've seen except for the old Mogo for Windows binary. I'd like to know how they do this. ___ Computer-go mailing list Computer-go@computer-go.org http://computer-go.org/mailman/listinfo/computer-go ___ Computer-go mailing list Computer-go@computer-go.org http://computer-go.org/mailman/listinfo/computer-go
Re: [Computer-go] Seki in playouts
On Wed, Apr 15, 2015 at 12:24 PM, Igor Polyakov weiqiprogramm...@gmail.com wrote: 5. But it misses this because squeezing leads to a few accidental losses in playouts where black plays something that white doesn't respond to My two cents: just prevent the accidental losses in playouts then the program will play B8 correctly. Aja ___ Computer-go mailing list Computer-go@computer-go.org http://computer-go.org/mailman/listinfo/computer-go
[Computer-go] Seki in playouts
I have an interesting problem with my program. 1. I have self-atari detection, but self-atari is allowed for smaller groups like the two stone group because it can make a nakade. 2. Self-atari detection means that in most playouts the program will let the black player suicide, but it won't let the white player suicide because the group is too large. 3. Therefore, it has white winning playing D9 or D7 because the playouts have black suicide 4. It has to squeeze right now because the seki loses the game, while the squeeze wins it. 5. But it misses this because squeezing leads to a few accidental losses in playouts where black plays something that white doesn't respond to I have thought about this and there's a few solutions: 1. Allow the program to pass late in playouts. In the current implementation this leads to accidental pass-pass playouts when the game is not finished and the program is poor at evaluating boards with dead stones on them. 1a. Implement a special passing type that doesn't end the game, but only allows you take back ko or just let your opponent finish their game when you still have legal moves left you don't want to take 1b. Make the program good at deciding dead stones somehow and not worry about pass-pass in playouts as long as it's late enough (what's late enough? 75% of the board filled?) 2. Have custom seki logic that will just prevent you from playing a nakade shape against a group that already has an eye I noticed that every program does this correctly that I've seen except for the old Mogo for Windows binary. I'd like to know how they do this. seki problem.sgf Description: application/go-sgf ___ Computer-go mailing list Computer-go@computer-go.org http://computer-go.org/mailman/listinfo/computer-go
[computer-go] Seki in playouts
I did not realize that his program, even with a large tree, would not be able to recognize the seki. I knew of course that the original Mogo playouts had this problem, but I thought all strong programs had solved it by now... Hello Erik, seki in playouts is still an unsolved problem for Fuego as well. I have tried many times to fix it by disabling selfatari moves. But anything I tried made the program measurably weaker overall. Martin ___ computer-go mailing list computer-go@computer-go.org http://www.computer-go.org/mailman/listinfo/computer-go/
Re: [computer-go] Seki in playouts
There are times when self-atari is the correct play. Seki and nakade are probably going to require a global analysis to handle properly. Terry McIntyre [EMAIL PROTECTED] “Wherever is found what is called a paternal government, there is found state education. It has been discovered that the best way to insure implicit obedience is to commence tyranny in the nursery.” Benjamin Disraeli, Speech in the House of Commons [June 15, 1874] - Original Message From: Martin Mueller [EMAIL PROTECTED] To: computer-go@computer-go.org Sent: Tuesday, August 12, 2008 9:18:16 AM Subject: [computer-go] Seki in playouts I did not realize that his program, even with a large tree, would not be able to recognize the seki. I knew of course that the original Mogo playouts had this problem, but I thought all strong programs had solved it by now... Hello Erik, seki in playouts is still an unsolved problem for Fuego as well. I have tried many times to fix it by disabling selfatari moves. But anything I tried made the program measurably weaker overall. Martin ___ computer-go mailing list computer-go@computer-go.org http://www.computer-go.org/mailman/listinfo/computer-go/ ___ computer-go mailing list computer-go@computer-go.org http://www.computer-go.org/mailman/listinfo/computer-go/
Re: [computer-go] Seki in playouts
Martin Mueller wrote: I did not realize that his program, even with a large tree, would not be able to recognize the seki. I knew of course that the original Mogo playouts had this problem, but I thought all strong programs had solved it by now... Hello Erik, seki in playouts is still an unsolved problem for Fuego as well. I have tried many times to fix it by disabling selfatari moves. But anything I tried made the program measurably weaker overall. Martin Crazy Stone now evaluates most usual cases of seki correctly. The way I do it is extremely complicated. I did not measure an improvement in playing strength from that work, but the program does not play weaker either. I am happy that it now scores every game correctly, and avoids some horrible moves caused by misunderstanding of seki. Also, seki knowledge is necessary to play games with Japanese rules (tournaments in Japan are played with Japanese rules). The sgf file in attachment contains a variety of interesting seki and non-seki situations that the playouts of Crazy Stone evaluate correctly. I believe it contains all the usual kinds. Some sekis are so complicated that it is not reasonable to evaluate them in the playouts. That page is fun: http://senseis.xmp.net/?StrangeSekis My warning: if you'd like seki knowledge in your playouts, then get ready for headaches. Rémi Seki-0004.sgf Description: application/go-sgf ___ computer-go mailing list computer-go@computer-go.org http://www.computer-go.org/mailman/listinfo/computer-go/
Re: [computer-go] Seki in playouts
On Tue, Aug 12, 2008 at 6:18 PM, Martin Mueller [EMAIL PROTECTED] wrote: I did not realize that his program, even with a large tree, would not be able to recognize the seki. I knew of course that the original Mogo playouts had this problem, but I thought all strong programs had solved it by now... Hello Erik, seki in playouts is still an unsolved problem for Fuego as well. I have tried many times to fix it by disabling selfatari moves. But anything I tried made the program measurably weaker overall. Hi Martin, The tricky thing is to determine *when* to disable self-atari moves. Forgive me for not going into details now; if you ask me again in Beijing or after the Olympiad I'll say more. Erik ___ computer-go mailing list computer-go@computer-go.org http://www.computer-go.org/mailman/listinfo/computer-go/
