Author: Uri Blass
Date: 10:20:05 01/28/05
Go up one level in this thread
On January 28, 2005 at 12:08:47, Norm Pollock wrote: >On January 28, 2005 at 11:45:29, Uri Blass wrote: > >>On January 28, 2005 at 10:55:23, Norm Pollock wrote: >> >>>On January 28, 2005 at 10:44:59, Matthias Gemuh wrote: >>> >>>>On January 28, 2005 at 09:19:47, Norm Pollock wrote: >>>> >>>>>Stefan, >>>>> >>>>>I would like to ask you why the commercial engines do not use a double book - >>>>>one book for moves as white and another for moves as black. By using one book, >>>>>based a single collection of games, black for example, is basing its opening on >>>>>games that black lost. >>>>> >>>>>-Norm >>>> >>>> >>>>The book is basically 2 books in file because the side to move is part of the >>>>hash key used to probe the file for moves. >>>> >>>>/Matthias. >>> >>>From an operational standpoint I agree that the book is really 2 books. >>> >>>I am considering how the book (or 2 books from an operational standpoint) is >>>created. It is created from pgns that have games of 1-0, =-= and 0-1 in them. So >>>white is using "its" book based on pgns that include 0-1, and black is using >>>"its" book based on pgns that include 1-0. >>> >>>Uri's comment about Fritz shows that Fritz handles this by commenting out some >>>weak moves. But how complete and accurate could this be? Isn't it better to >>>first base an opening book on games white (for example) won or drew against a >>>highly rated opponent, and then require a high frequency for any move to be >>>entered into the book? >> >>This is almost the way that I do it in movei >> >>The public book for white is based only on games that white won and I need >>minimal frequency of 5 times. >>the public book for black is based only on games that black got at least a draw >>and I need minimal frequency of 5 times. >> >>I think that the games are all games of GM's that I downloaded from the >>internet. >> >>I do not think that the way that I do it is optimal and I doubt if using >>statistics to decide about moves is a good idea because it is possible that a >>move was considered as good in the past and later some refutation was found. >> >>I think that some expert who write the book manually is better and I think that >>sandro writes the commercial book for shredder manually so I expect shredder uci >>to have better book than the book that movei has. >> >>Uri > >I have a few questions about how you made your book. > >Have you tested your engine with book vs your engine without book, preferably at >short & blitz time controls where a book has extra importance? No Does your book >really make a measurable improvement? I do not know Also did you test your engine with/without >book against a gauntlet of 4 engines of comparable strength using their books? No > >What is the minimum elo of games in your database for your book? the minimum elo is 2420 There is only one game when the loser has rating of 2420 [Event "Brussels-simul SW19"] [Site "?"] [Date "1993.??.??"] [Round "?"] [White "Kasparov, Gary"] [Black "Lane, Gary W"] [Result "1-0"] [ECO "E60"] [WhiteElo "2805"] [BlackElo "2420"] [PlyCount "67"] [EventDate "1993.??.??"] 1. d4 Nf6 2. c4 g6 3. g3 Bg7 4. Bg2 O-O 5. Nf3 d6 6. O-O Nbd7 7. Qc2 e5 8. Rd1 Qe7 9. Nc3 c6 10. d5 c5 11. e4 Ng4 12. Rb1 f5 13. Ng5 f4 14. Ne6 fxg3 15. fxg3 Rf2 16. Qd3 Qf7 17. Rf1 Nf8 18. Be3 Rxf1+ 19. Rxf1 Qe7 20. Bg5 Bf6 21. Bxf6 Nxf6 22. Qf3 N8d7 23. g4 h6 24. h4 a6 25. h5 Qf7 26. Bh3 gxh5 27. gxh5 Kh8 28. Nc7 Rb8 29. Bxd7 Qg7+ 30. Kh2 Nxd7 31. Ne6 Qe7 32. Qg3 Nf6 33. Qh4 Nxd5 34. Rf8+ 1-0 How many games >are in the database? 50,000 What are the dates on those games? The oldest game that I find is from 1894 but most of them are from 1980-2003 There are no games from 2004-2005. [Event "R11"] [Site "?"] [Date "1894.??.??"] [Round "?"] [White "Pillsbury, Harry N"] [Black "Steinitz, Wilhelm"] [Result "0-1"] [ECO "D26"] [WhiteElo "2630"] [BlackElo "2650"] [PlyCount "74"] [EventDate "1894.??.??"] 1. d4 d5 2. c4 dxc4 3. Nf3 e6 4. e3 c5 5. Nc3 Nc6 6. Bxc4 Nf6 7. O-O cxd4 8. exd4 Be7 9. Bf4 O-O 10. Rc1 Qb6 11. Nb5 Ne8 12. Re1 Na5 13. Bd3 Bd7 14. Nc7 Rc8 15. Nd5 exd5 16. Rxe7 Nf6 17. Ng5 Bg4 18. Bxh7+ Nxh7 19. Qxg4 Rxc1+ 20. Bxc1 Nf6 21. Qd1 Nc6 22. Re1 Qxd4 23. Nf3 Qb6 24. Bg5 Qxb2 25. Re2 Qb5 26. Bxf6 gxf6 27. Rd2 Rd8 28. Nh4 d4 29. Rd3 Ne5 30. Rb3 Qc6 31. Rg3+ Kf8 32. Qd2 Rc8 33. Qh6+ Ke7 34. Nf5+ Kd7 35. h4 Qc1+ 36. Qxc1 Rxc1+ 37. Kh2 d3 0-1 Would you consider >enlarging the database you based your book upon? I did not think much of it. Would you consider a higher >frequency of occurrences (like around 12)? I do not know if it is a good idea. peter berger played with Movei games and it lost games against Junior when it's book was too short. Leo is using in WBEC another book when he is using different database and minimal frequency of 2 games. > >Did you check out the database I put up on Peter Skinner's crafty-chess.com ? >It has about 60,000 games, elos 2400+, no duplicates, long-time controls, min 20 >moves, and relatively recent (since year 2000). No Maybe it is a better database. Note that it is possible to build book for movei directly from 2 pgn's(one for white and one for black) and everyone can do it. Instruction inside the readme file: Instructions to create book at console mode 1)have 2 pgn one for white moves and one for black moves 2)Rename the pgn for white to gameswhite.pgn 3)Rename the book for black to gamesblack.pgn 4)Run the program at console mode and type createbook 5)type numbers for maximal ply and minimal frequency when movei asks for it. 6)Wait until movei type the words book created. 7)type quit Uri
This page took 0 seconds to execute
Last modified: Thu, 15 Apr 21 08:11:13 -0700
Current Computer Chess Club Forums at Talkchess. This site by Sean Mintz.