Re: [computer-go] MC approach
On Wed, Feb 07, 2007 at 02:41:22PM -0600, Nick Apperson wrote: If it only did one playout you would be right, but imagine the following cases: case 1: White wins by .5 x 100, Black wins by .5 x 100 case 2: White wins by 100.5 x 91, Black wins by .5 x 109 the method that takes into account score would prefer the second case even though it has a lower winning percentage that may be represented by the fact that white is making an overplay for instance. Obviously this is just one example, but there are many cases like this and overplays tend to be priveledged in a sense I would suspect with this kind of algorithm. I have been thinking about this, and have to agree with you, averaging the results gives pretty small numbers, that can easily be disturbed by adding the winning scores to the mixture. But there is a way. If we do N play-outs, the effect of any single of them is 1/N. If we make sure to scale the score to be less than half of this, it can not disturb anything in cases where the number of wins is different. Only in cases with exactly the same number of wins in the play-outs, would the score break the tie. In other words my large constant of 1000 was far too small. It would have to be something like 2NM, where M is the maximum score (say 361). Round it up to 1000N, and we should be safe. I still believe it would make endgames look more reasonable, and possibly even better, in case the winning program has overlooked a detail somewhere, having a large margin of points on the board should act as an insurance against small blunders. Or am still missing something obvious? - Heikki -- Heikki Levanto In Murphy We Turst heikki (at) lsd (dot) dk ___ computer-go mailing list computer-go@computer-go.org http://www.computer-go.org/mailman/listinfo/computer-go/
Re: Re[4]: [computer-go] Why not forums?
On 7-feb-07, at 02:20, Dmitry Kamenetsky wrote: I have been reading this list for nearly a year now and it is very discouraging to receive so much criticism for my first post. Don't be discouraged please. The big-mouths don't always represent what the majority thinks. The yahoo groups was merely an example to show how easy it is to get a forum started. I also agree that yahoo appends too much spam to its forums and I am sure there are many much much better free forums out there. The forums that I really like are the TopCoder forums (http:// forums.topcoder.com/). I like them for these reasons: * One can post in various sections. The sections we can have here could be: Monte Carlo Go, Search in Go, Learning in Go, CGOS, KGS, Human Go. * Threads are easy to find and each thread has a post count. The post count is a good indication of how interesting that thread is. For example if there are many threads that I haven't had time to read, then I will first read the ones with the most post count. * Different viewing options: flat (newest first), threaded or tree. These can be useful for various purposes. * Each post has a '+' and '-' associated with it. This means that if you agree with the post then you simply press the '+' button and the plus count goes up, similarly if you disagree you press the '-' button. This serves two purposes: you don't have to post extra posts just to show your agreement/disagreement, which saves space and your time; also this is a great way to make votes - those in favour press '+', those against press '-'. * Each post is associated with a date and time. Also it is easy to ressurect threads that are years old. * If you had a typo or a mistake in your post, you can easily edit it. This is extremely useful. * It is not necessary, but it is always nice to see who you are talking to. * There is a very powerful message searching engine, which incorporates: section type, date range and member name. * You can watch threads that are of interest to you. I hope I have given some good reasons for having a forum. Since so many people here are against losing the list, why not the following: we keep the list, but give members the option of using a forum? This way we can all be happy :) I agree a forum would be a superior platform. The reasons against it I see posted cling too much to old known ways instead of being open to new possibilities. A typical way to respond to this is to point out the deficiencies of one particular example and use it as an argument not to change. People don't like change until it has happened. The computer-Go community is just as conservative in this respect as any other. There's no reason why we can't have a forum that includes an option of having all messages e-mailed to you and allow for posting through an e-mail reply. In that sense it would act the same as the current mailing-list for those who don't like to have any extra features. It's just a matter of finding one that suits our needs best. One particular feature I've come to appreciate on forums is a 'recommendation' feature. Every member can recommend a post he/she likes in particular. When short in time one can select to read the messages with a lot of recommendations only. This is similar to the '+' and '-' feature you mentioned. Threading of messages on the same subject is a very useful feature too of course. The number of messages posted to this list is rather limited, so a mailing-list still works. So there's no screaming need for change. But if someone can find a good forum to act as a host instead it would be an improvement. Mark ___ computer-go mailing list computer-go@computer-go.org http://www.computer-go.org/mailman/listinfo/computer-go/
Re: Re[4]: [computer-go] Why not forums?
On Sun, 2007-02-11 at 10:59 -0200, Mark Boon wrote: Don't be discouraged please. The big-mouths don't always represent what the majority thinks. The opinions expressed for not wanting to move to a forum were polite and thoughtful. Calling them big-mouths is uncalled for. It's also quite clear by the number of responses from different people (as opposed to a vocal minority) that the majority does not want to move to a web forum. I agree a forum would be a superior platform. The reasons against it I see posted cling too much to old known ways instead of being open to new possibilities. I have tried web forums many times and they aren't as usable. Something like Slashdot works well on the web because of the sheer volume, and the user moderation keeps it readable. However, the typical list/newsgroup with around 20 messages per day or less does not benefit. It's not a matter of clinging to old ways. It's a matter of bsaic usability that is lost by moving to a web page over a dedicated reader. There's no reason why we can't have a forum that includes an option of having all messages e-mailed to you and allow for posting through an e-mail reply. In that sense it would act the same as the current mailing-list for those who don't like to have any extra features. It's just a matter of finding one that suits our needs best. And has already been mentioned, there's no reason why the *existing* list can't be fed to a web forum, instead of asking people to move. And in fact there is already at least one such web interface that hosts this list: gmane. One particular feature I've come to appreciate on forums is a 'recommendation' feature. Useful for Slashdot; not so useful for a small mailing list. Threading of messages on the same subject is a very useful feature too of course. And also available on many email clients, as has already been mentioned. The number of messages posted to this list is rather limited, so a mailing-list still works. So there's no screaming need for change. Agreed. The thread had died a graceful death, too. *sigh* But if someone can find a good forum to act as a host instead it would be an improvement. Asking people to resubscribe to a new host would not be an improvement. Putting up a forum that seamlessly works with the existing environment (like gmane does) would be ok. -Jeff ___ computer-go mailing list computer-go@computer-go.org http://www.computer-go.org/mailman/listinfo/computer-go/
Re: Re[4]: [computer-go] Why not forums?
On 2/11/07, Jeff Nowakowski [EMAIL PROTECTED] wrote: On Sun, 2007-02-11 at 10:59 -0200, Mark Boon wrote: Don't be discouraged please. The big-mouths don't always represent what the majority thinks. The opinions expressed for not wanting to move to a forum were polite and thoughtful. Calling them big-mouths is uncalled for. It's also quite clear by the number of responses from different people (as opposed to a vocal minority) that the majority does not want to move to a web forum. I agree a forum would be a superior platform. The reasons against it I see posted cling too much to old known ways instead of being open to new possibilities. I have tried web forums many times and they aren't as usable. Something like Slashdot works well on the web because of the sheer volume, and the user moderation keeps it readable. However, the typical list/newsgroup with around 20 messages per day or less does not benefit. It's not a matter of clinging to old ways. It's a matter of bsaic usability that is lost by moving to a web page over a dedicated reader. There's no reason why we can't have a forum that includes an option of having all messages e-mailed to you and allow for posting through an e-mail reply. In that sense it would act the same as the current mailing-list for those who don't like to have any extra features. It's just a matter of finding one that suits our needs best. And has already been mentioned, there's no reason why the *existing* list can't be fed to a web forum, instead of asking people to move. And in fact there is already at least one such web interface that hosts this list: gmane. One particular feature I've come to appreciate on forums is a 'recommendation' feature. Useful for Slashdot; not so useful for a small mailing list. Threading of messages on the same subject is a very useful feature too of course. And also available on many email clients, as has already been mentioned. The number of messages posted to this list is rather limited, so a mailing-list still works. So there's no screaming need for change. Agreed. The thread had died a graceful death, too. *sigh* But if someone can find a good forum to act as a host instead it would be an improvement. Asking people to resubscribe to a new host would not be an improvement. Putting up a forum that seamlessly works with the existing environment (like gmane does) would be ok. -Jeff Amen. E. ___ computer-go mailing list computer-go@computer-go.org http://www.computer-go.org/mailman/listinfo/computer-go/
Re: [computer-go] Why not forums?
Dmitry Kamenetsky wrote: I have been reading this list for nearly a year now and it is very discouraging to receive so much criticism for my first post. Sadly, you chose a topic that is close to the hearts of many. I like the style of this follow up post much more than the original in that you try to give your reasons for wanting a forum. By giving a post that shows time and effort to reflect on an issue and articulate an argument, you'll tend to get similar posts in response. If your suggestion really is to go somewhere, someone really needs to provide a balanced perspective on the change from e-mail/newsgroup to forum. It's already come up that a lot of the features you're looking for are available in various e-mail/newsgroup clients. It's very important to compare/contrast what can be done through a reader of someone's choice verses a very specific web-based forum where everyone has no choice. As an example, my client supports threads with watch/ignore options, custom filters to posts or sort into folders, some quick search options (such as sender, topic, keywords), saved searches (allowing easy repeat later), and other more typical features such as sorting and advanced filters. Your list shows only two things that are novel relative to my reader. They are the +/- and the editing of a post after you've posted it. I personally find editing of a post after others have responded to it to be a bit dangerous of a feature. I like the +/- thing. Sadly, those two things are not enough for me to change how I read through the computer go mailing list. If it was the only mailing list that I subscribe to, that might be a different story. A common (and powerful) interface for all my mailing lists is more valuable to me than a bunch of slightly more powerful web pages that I have to visit in sequence. It's been mentioned to have a combination forum/mailing list/newsgroup, and without any very compelling arguments one way or the other, I think that solution really is best. Obviously, even a change to the host of the mailing list (for a better web interface) will receive resistance, but would at least get less. I'm sure others will simply say to petition gmane to update their interface for what you want. The yahoo groups was merely an example to show how easy it is to get a forum started. I also agree that yahoo appends too much spam to its forums and I am sure there are many much much better free forums out there. The forums that I really like are the TopCoder forums (http://forums.topcoder.com/). I like them for these reasons: * One can post in various sections. The sections we can have here could be: Monte Carlo Go, Search in Go, Learning in Go, CGOS, KGS, Human Go. * Threads are easy to find and each thread has a post count. The post count is a good indication of how interesting that thread is. For example if there are many threads that I haven't had time to read, then I will first read the ones with the most post count. * Different viewing options: flat (newest first), threaded or tree. These can be useful for various purposes. * Each post has a '+' and '-' associated with it. This means that if you agree with the post then you simply press the '+' button and the plus count goes up, similarly if you disagree you press the '-' button. This serves two purposes: you don't have to post extra posts just to show your agreement/disagreement, which saves space and your time; also this is a great way to make votes - those in favour press '+', those against press '-'. * Each post is associated with a date and time. Also it is easy to ressurect threads that are years old. * If you had a typo or a mistake in your post, you can easily edit it. This is extremely useful. * It is not necessary, but it is always nice to see who you are talking to. * There is a very powerful message searching engine, which incorporates: section type, date range and member name. * You can watch threads that are of interest to you. I hope I have given some good reasons for having a forum. Since so many people here are against losing the list, why not the following: we keep the list, but give members the option of using a forum? This way we can all be happy :) ___ 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] Zobrist hashing with easy transformation comparison
Please do. I will put it on a web page. But I need some time. My job keeps me very busy right now. But I'm not sure I will post the statistical analysis (it was almost ten hand writen pages, and I'm not sure I still have them). Have You performed an empirical test for collisions? No, analysis was analytic. I've used the scheme in different ways, and since I knew were was the defect I put extra code to protect from the defect. This proved to be usefull... I was able to catch collisions at low rate in practice, but this rate would have been unacceptable if I had not been able to detect them. The defect is as follow: if you have 2 different board configurations, the probability that they have the same hash key can be as low as 1/256 (for a 64-bit key) if the difference between the 2 configurations has self symmetries. Anti Huima's scheme had the same defect, except the probability was 1. That's why I've been able to isolate it: I always had collisions between the same positions, and it didn't depend on the way random bits were generated. Antoine ___ computer-go mailing list computer-go@computer-go.org http://www.computer-go.org/mailman/listinfo/computer-go/
Re: [computer-go] Serializing a very large object in Java
Peter Drake wrote: out.writeObject(root); Storing the root node of the Monte Carlo search will get storeObject() called on all the siblings and children (assuming you are using an implementation similar to the one on http://senseis.xmp.net/?UCT. With 10.000 nodes, the depth of the tree is a little less than with 2.000.000 nodes. Since for each sibling (important) and each child (not so important), the writeObject() method is called, you get that stack overflow. Since there are as many siblings per move as valid moves, the recursion depth grows quite quickly. You can avoid that by not calling writeObject(this.sibling), but doing that in a while (...) loop. Roland ___ computer-go mailing list computer-go@computer-go.org http://www.computer-go.org/mailman/listinfo/computer-go/
Re: [computer-go] Monte-Carlo Go simulation
Alain's point, that knowledge can both help narrow the search to good moves and at the same time steer you away from the best move is absolutely true in SlugGo's case. I completely agree with that. However can we agree that we want a better player in a whole, and not only better in some particular positions? So perhaps, I think, behind far from the best move, while playing always good moves is already good no? Sylvain ___ computer-go mailing list computer-go@computer-go.org http://www.computer-go.org/mailman/listinfo/computer-go/
Re: [computer-go] Zobrist hashing with easy transformation comparison
On 2/10/07, Łukasz Lew [EMAIL PROTECTED] wrote: On 2/10/07, Antoine de Maricourt [EMAIL PROTECTED] wrote: If there is strong interest, I can post the scheme. Please do. Since Antoine claims there is only on solution I might as well post mine ;-) mirroring: [abcdefgh] - [hgfedcba] rotation: [abcdefgh] - [cdefghab] This scheme follows trivially from dividing the square in 8 triangular regions, and assigning each a letter. If you want to include color symmetry you need to change the operators (xor doesn't work any more) or increase the number of segments. Erik This is one out of the 3 possibilities that were left once we eliminated obvious defects (the ones the original proposal by Anti Huima suffered). However, if my analysis was right, this scheme was the one that introduces the biggest weakness in the key. That's why I didn't keep it. Antoine. ___ computer-go mailing list computer-go@computer-go.org http://www.computer-go.org/mailman/listinfo/computer-go/
