Author: Robert Hyatt
Date: 21:01:13 02/28/04
Go up one level in this thread
On February 27, 2004 at 23:59:05, Matthew Hull wrote: >On February 27, 2004 at 23:00:40, Robert Hyatt wrote: > >>On February 27, 2004 at 17:28:25, Matthew Hull wrote: >> >>>This seems to be a "dumb" horizon effect where the book draw is avoided, yet >>>there is no chance to win anyway. I've seen other programs fall into this. >>>Does crafty handle this any better? >> >>You will have to explain more about what happened. > > >White has a knight (not enough mating material), crafty has a pawn. Why does >white not take the pawn? Is this a kind of horizon effect where if the pawn >goes, white says it's a book draw, but if the pawn stays, white is up 2 pawns or >something? OK. Most programs know that KN vs K is a draw. Some (crafty) realize that if it is, instead, KN vs KP, then any winning chances are with the KP side, not the KN side. Others simply say "KN vs K is draw" while "KN vs KP is not a draw". What happened here I don't know, not knowing the other program. But it is not a "opening book" issue at all. The opening book only takes the engine through the first 10-20 moves typically. > > >>IE I don't know what Crafty >>played from book, and from search, nor what its scores showed. Against humans, >>I play a pretty wide book, to give variety. When winning is important, or when >>playing computers, I reduce this variability a whole lot. >> >>Playing a wide book can lead to strange things... >> >> >>> >>> >>> >>>[Event "ICS Rated Blitz match"] >>>[Site "www-eds-proxy.sabre.com"] >>>[Date "2004.02.27"] >>>[Round "-"] >>>[White "pathologist"] >>>[Black "crafty"] >>>[Result "*"] >>>[WhiteElo "2832"] >>>[BlackElo "2795"] >>>[TimeControl "300+3"] >>> >>>1. e4 e5 2. Nf3 Nc6 3. Bb5 a6 4. Ba4 Nf6 5. O-O Nxe4 6. d4 Be7 7. Re1 b5 8. >>>Rxe4 d5 9. Nxe5 Nxe5 10. Rxe5 bxa4 11. Nc3 O-O 12. Rxd5 Bd6 13. Bf4 Rb8 14. >>>Qd2 Be6 15. Ra5 Rxb2 16. Bxd6 Qxd6 17. Qd3 a3 18. Rxa6 Bf5 19. Rxd6 Bxd3 >>>20. Rc6 Rxc2 21. Rxc7 Rb8 22. h4 h5 23. Re1 Rbb2 24. Re8+ Kh7 25. Re3 Bg6 >>>26. Rf3 Rc1+ 27. Kh2 Rxa2 28. Nxa2 Rxc7 29. Rxa3 Rc4 30. d5 Rxh4+ 31. Kg1 >>>Rd4 32. Ra5 Rd1+ 33. Kh2 Rd2 34. Nc3 Kh6 35. Rc5 Rxf2 36. d6 Rd2 37. Rd5 >>>Rxd5 38. Nxd5 Bf5 39. Nb6 Kg5 40. d7 Bxd7 41. Nxd7 Kf4 42. Kh3 g6 43. Nf8 >>>Kg5 44. Nh7+ Kf5 45. Kh4 Kf4 46. Nf6 Kf5 47. Ng8 Kf4 48. Ne7 Ke3 49. Nc8 >>>Kf4 50. Ne7 g5+ 51. Kxh5 Kg3 52. Nf5+ Kxg2 53. Kxg5 Kf2 54. Kf6 Ke2 55. Ne7 >>>Kd2 56. Nd5 Kc2 57. Nb4+ Kb3 58. Nd3 Kc2 59. Nc5 Kb2 60. Nd7 Kc2 61. Ne5 >>>Kb2 62. Nc6 Kc2 63. Ne5 Kb2 64. Ng4 Kc2 65. Kf5 Kb2 66. Nf6 Kc2 67. Nd5 Kb2
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.