Laskos wrote:The conclusion would by that Syzygy WDL and Scorpio are not helping SF to convert root TB wins. Maybe it would be better to switch them off when a TB position is reached.
In some cases bitbases can hurt to defend against root TB positions.
[D]8/2K3p1/4k3/7r/8/8/R7/8 w - - 0 49
Stockfish with Scorpio egbbs defend this endgame not very well. White plays 1.Re2+ and after Re5 he trades the rooks with 2.Rxe5+.
[D]8/2K3p1/8/4k3/8/8/8/8 w - - 0 51
This makes it easy to win, even for weaker players like Beowulf as example. Stockfish with egbb gets mated soon.
Code: Select all
[Event "Computer Chess Game"]
[Site "Home"]
[Date "2014.02.06"]
[Round "-"]
[White "Stockfish 2014 (Scorpio)"]
[Black "Beowulf 2.4a"]
[Result "0-1"]
[TimeControl "40/60"]
[FEN "8/2K3p1/4k3/7r/8/8/R7/8 w - - 0 1"]
[SetUp "1"]
{--------------
. . . . . . . .
. . K . . . p .
. . . . k . . .
. . . . . . . r
. . . . . . . .
. . . . . . . .
R . . . . . . .
. . . . . . . .
white to play
--------------}
1. Re2+ {-99,90/76} Re5 {+1,49/10 1,0} 2. Rxe5+ {-100,63/100 0,2} Kxe5
{+111,77/17 0,4} 3. Kd7 {-103,02/69 0,8} g5 {+327,47/17 1,2} 4. Ke7
{-103,12/77 0,8} g4 {+6,31/2 0,2} 5. Kd7 {-103,29/100 0,1} g3 {+6,99/2 0,1}
6. Kc6 {-103,36/100 0,2} g2 {+7,58/2 0,2} 7. Kc5 {-104,65/100 0,1} g1=Q+
{+327,47/2 0,1} 8. Kc4 {-99,88/36 0,9} Qd4+ {+112,06/2 0,2} 9. Kb3
{-99,90/70 0,8} Kd5 {+111,80/3 0,2} 10. Ka2 {-99,92/100 0,2} Kc4
{+327,47/2 0,2} 11. Kb1 {-99,94/100 0,2} Kc3 {+327,47/2 0,2} 12. Ka1
{-99,96/100 0,2} Kb3+ {+327,48/2 0,2} 13. Kb1 {+0,00/1 0,2} Qb2#
{+327,66/2 0,1}
{Xboard adjudication: Checkmate} 0-1
In fact, this endgame should be won for black. But white can defend much harder, shown by Stockfish without Scorpio egbbs. Now white managed to draw against the same opponent!
Code: Select all
[Event "Computer Chess Game"]
[Site "Home"]
[Date "2014.02.06"]
[Round "-"]
[White "Stockfish 2014"]
[Black "Beowulf 2.4a"]
[Result "1/2-1/2"]
[TimeControl "40/60"]
[FEN "8/2K3p1/4k3/7r/8/8/R7/8 w - - 0 1"]
[SetUp "1"]
{--------------
. . . . . . . .
. . K . . . p .
. . . . k . . .
. . . . . . . r
. . . . . . . .
. . . . . . . .
R . . . . . . .
. . . . . . . .
white to play
--------------}
1. Ra6+ {-1,95/21} Kf7 {+1,45/10 0,9} 2. Ra7 {-2,11/25 0,9} Rf5
{+1,49/10 1,4} 3. Kc6+ {-2,35/24 1,0} Kf6 {+1,53/12 1,4} 4. Ra4
{-3,02/25 1,4} g5 {+1,63/11 1,4} 5. Kd7 {-3,76/25 2,1} Rd5+ {+1,74/10 1,1}
6. Kc6 {-4,77/25 4} Rd8 {+1,85/11 1,4} 7. Rb4 {-5,39/21 2,6} Rg8
{+2,05/11 1,5} 8. Kd5 {-5,56/21 1,3} g4 {+2,55/11 1,4} 9. Ke4
{-5,64/25 0,8} g3 {+2,81/10 1,7} 10. Rb6+ {-0,02/23 1,0} Ke7 {+0,18/11 1,2}
11. Rb1 {+0,00/32 0,7} Kd6 {+0,08/11 1,4} 12. Rd1+ {+0,00/37 0,8} Kc5
{+0,06/12 1,4} 13. Rc1+ {+0,00/39 0,9} Kb4 {+0,06/12 1,0} 14. Kf3
{+0,00/39 0,9} Rg7 {+0,04/11 1,1} 15. Rb1+ {+0,00/40 0,9} Kc3
{+0,07/12 1,3} 16. Rg1 {+0,00/45 0,8} Kd3 {+0,07/11 1,1} 17. Rxg3
{+0,00/38 0,9} Rf7+ {+0,05/10 1,4} 18. Kg4+ {+0,00/41 0,9} Ke4
{+0,06/11 1,3} 19. Rb3 {+0,00/40 1,0} Rg7+ {+0,06/11 1,5} 20. Kh3
{+0,00/46 1,0} Kd4 {+0,05/11 1,4} 21. Rb4+ {+0,00/39 0,9} Kd5
{+0,05/11 1,2} 22. Rg4 {+0,00/42 1,1} Rh7+ {+0,04/10 1,1} 23. Kg3
{+0,00/46 1,0} Rf7 {+0,04/11 1,5} 24. Rf4 {+0,00/48 1,1} Re7 {+0,02/10 1,3}
25. Kg4 {+0,00/45 1,1} Re1 {+0,01/11 1,5} 26. Rf5+ {+0,00/47 1,2} Ke4
{+0,02/11 1,0} 27. Rf4+ {+0,00/52 1,1} Ke5 {+0,01/12 1,5} 28. Rf5+
{+0,00/51 1,2} Kd6 {+0,00/12 1,5} 29. Rf3 {+0,00/43 1,1} Kc5 {+0,00/11 1,5}
30. Rf5+ {+0,00/55 1,3} Kc6 {+0,00/12 1,5} 31. Rf6+ {+0,00/54 1,2} Kd5
{+0,00/12 1,1} 32. Rf5+ {+0,00/68 1,3} Ke4 {+0,00/13 1,6} 33. Rf4+
{+0,00/67 1,4} Ke5 {+0,00/14 1,8} 34. Rf5+ {+0,00/72 1,5} Kd6
{+0,00/14 1,8} 35. Rf3 {+0,00/74 1,7} Kc5 {+0,00/13 1,8} 36. Rf5+
{+0,00/78 1,8} Kc6 {+0,00/14 1,8} 37. Rf6+ {+0,00/80 1,9} Kd5
{+0,00/14 1,9} 38. Rf5+ {+0,00/86 2,3}
{Draw by repetition} 1/2-1/2
Stockfish with Syzygy endgame bases managed to draw too.
Code: Select all
[Event "Computer Chess Game"]
[Site "Home"]
[Date "2014.02.06"]
[Round "-"]
[White "Stockfish 2014 (Syzygy)"]
[Black "Beowulf 2.4a"]
[Result "1/2-1/2"]
[TimeControl "40/60"]
[FEN "8/2K3p1/4k3/7r/8/8/R7/8 w - - 0 1"]
[SetUp "1"]
{--------------
. . . . . . . .
. . K . . . p .
. . . . k . . .
. . . . . . . r
. . . . . . . .
. . . . . . . .
R . . . . . . .
. . . . . . . .
white to play
--------------}
1. Ra6+ {-151,00/21} Kf7 {+1,45/10 0,9} 2. Ra7 {-151,00/25 0,9} Rf5
{+1,49/10 1,4} 3. Kc6+ {-151,00/24 1,0} Kf6 {+1,54/12 1,4} 4. Ra4
{-151,00/25 1,5} g5 {+1,61/11 1,4} 5. Kd7 {-151,00/25 2,2} Rd5+
{+1,72/10 1,0} 6. Kc6 {-151,00/25 4} Rd8 {+1,82/11 1,4} 7. Rb4
{-151,00/21 2,6} Rg8 {+2,02/11 1,4} 8. Kd5 {-151,00/20 0,9} g4
{+2,41/11 1,4} 9. Ke4 {-151,00/21 0,9} Kg5 {+1,79/10 1,4} 10. Rb1
{-151,00/23 0,7} Kh4 {+2,18/10 1,0} 11. Rd1 {-151,00/29 6} g3
{+2,38/11 1,4} 12. Kf3 {+0,00/1 0,2} Rf8+ {+1,79/11 3} 13. Kg2
{+0,00/1 0,2} Rf2+ {+1,79/12 1,3} 14. Kg1 {+0,00/32 0,8} Kh3 {+1,79/12 1,2}
15. Rd8 {+0,00/31 0,7} Rf4 {+1,79/12 1,2} 16. Rh8+ {+0,00/33 0,7} Rh4
{+1,79/14 1,1} 17. Rxh4+ {+0,00/100 0,6} Kxh4 {+2,56/2 0,2} 18. Kg2
{+0,00/1 0,1} Kg4 {+5,93/25 1,2} 19. Kg1 {+0,00/1 0,2} Kf5 {+5,93/23 1,5}
20. Kf1 {+0,00/100 0,2} Kg5 {+5,93/20 11} 21. Kg1 {+0,00/100 0,3} Kg4
{+2,68/23 1,0} 22. Kg2 {+0,00/1 0,2} Kf4 {+2,68/21 1,0} 23. Kg1
{+0,00/1 0,2} Kg5 {+0,00/23 0,2} 24. Kf1 {+0,00/100 0,2} Kf5 {+0,00/21 0,2}
25. Kg1 {+0,00/100 0,2} Ke5 {+0,00/21 0,2} 26. Kf1 {+0,00/100 0,2} Kf5
{+0,00/21 0,1} 27. Kg1 {+0,00/100 0,2} Ke5 {+0,00/21 0,2} 28. Kf1
{+0,00/100 0,2} Kf5 {+0,00/21 0,2}
{Draw by Repetition} 1/2-1/2
Also Stockfish with Gaviota bases managed to draw.
Code: Select all
Event "Computer Chess Game"]
[Site "Home"]
[Date "2014.02.06"]
[Round "-"]
[White "Stockfish DD (Gaviota)"]
[Black "Beowulf 2.4a"]
[Result "1/2-1/2"]
[TimeControl "40/60"]
[FEN "8/2K3p1/4k3/7r/8/8/R7/8 w - - 0 1"]
[SetUp "1"]
{--------------
. . . . . . . .
. . K . . . p .
. . . . k . . .
. . . . . . . r
. . . . . . . .
. . . . . . . .
R . . . . . . .
. . . . . . . .
white to play
--------------}
1. Ra6+ {-99,28/1} Kf7 {+1,45/10 0,9} 2. Ra7 {-99,30/1 0,3} Rf5
{+1,49/10 1,3} 3. Kb8+ {-99,32/1 0,2} Kf8 {+1,58/11 1,5} 4. Kc8
{-99,34/1 0,2} g5 {+1,71/11 1,3} 5. Ra4 {-99,36/1 0,2} Rf4 {+1,76/11 0,9}
6. Ra5 {-99,38/1 0,2} g4 {+1,91/12 1,3} 7. Kd7 {-99,40/1 0,2} g3
{+2,72/11 1,4} 8. Ke6 {+0,00/1 0,2} Rg4 {+2,86/11 1,4} 9. Ra1 {+0,00/1 0,2}
g2 {+2,87/12 1,4} 10. Rg1 {+0,00/1 0,2} Rg5 {+0,16/12 4} 11. Kf6
{+0,00/1 0,2} Rg7 {+0,08/11 1,4} 12. Ke5 {+0,00/1 0,2} Ke8 {+0,06/10 1,3}
13. Kd5 {+0,00/1 0,2} Rg4 {+0,16/11 0,9} 14. Ke6 {+0,00/1 0,2} Rg5
{+0,16/12 1,3} 15. Kf6 {+0,00/1 0,3} Rg8 {+0,08/11 1,4} 16. Kf5
{+0,00/1 0,2} Ke7 {+0,08/10 1,3} 17. Ke5 {+0,00/1 0,2} Rg4 {+0,08/10 1,3}
18. Kf5 {+0,00/1 0,2} Rg7 {+0,04/11 1,3} 19. Re1+ {+0,00/1 0,2} Kd6
{+0,14/12 1,3} 20. Rd1+ {+0,00/1 0,2} Kc5 {+0,14/13 1,3} 21. Rg1
{+0,00/1 0,3} Kc4 {+0,10/12 1,3} 22. Kf4 {+0,00/1 0,2} Kd3 {+0,08/11 1,0}
23. Kf3 {+0,00/1 0,3} Rg6 {+0,07/11 1,3} 24. Kf2 {+0,00/1 0,2} Rg5
{+0,06/10 1,1} 25. Rxg2 {+0,00/1 0,2} Rf5+ {+0,04/10 1,1} 26. Kg3
{+0,00/1 0,2} Ke3 {+0,05/11 1,4} 27. Rb2 {+0,00/1 0,2} Rg5+ {+0,06/11 1,4}
28. Kh4 {+0,00/1 0,2} Rg7 {+0,05/11 1,2} 29. Rb6 {+0,00/1 0,2} Kf4
{+0,05/11 1,5} 30. Kh3 {+0,00/1 0,2} Ke5 {+0,05/11 1,3} 31. Ra6
{+0,00/1 0,3} Kd5 {+0,05/11 1,4} 32. Ra2 {+0,00/1 0,2} Ke4 {+0,05/11 1,5}
33. Rg2 {+0,00/1 0,2} Rf7 {+0,05/12 1,6} 34. Kg3 {+0,00/1 0,2} Ke3
{+0,05/12 1,6} 35. Kh4 {+0,00/1 0,1} Rh7+ {+0,05/11 1,6} 36. Kg3
{+0,00/1 0,1} Ra7 {+0,04/12 1,7} 37. Kh4 {+0,00/1 0,2} Rf7 {+0,05/12 1,7}
38. Kg4 {+0,00/1 0,2} Rf4+ {+0,04/11 1,7} 39. Kh3 {+0,00/1 0,2} Rf6
{+0,04/11 1,3} 40. Rg5 {+0,00/1 0,1} Rf7 {+0,05/12 2,1} 41. Kh4
{+0,00/1 0,1} Kd4 {+0,04/11 1,4} 42. Rg6 {+0,00/1 0,1} Rf1 {+0,04/11 1,4}
43. Kh5 {+0,00/1 0,2} Kd5 {+0,04/11 1,4} 44. Kh6 {+0,00/1 0,1} Rf2
{+0,05/11 1,4} 45. Rg8 {+0,00/1 0,1} Ke6 {+0,05/11 1,4} 46. Rc8
{+0,00/1 0,1} Rg2 {+0,06/11 1,1} 47. Re8+ {+0,00/1 0,1} Kd7 {+0,05/13 1,4}
48. Re4 {+0,00/1 0,1} Kd6 {+0,05/12 1,4} 49. Re8 {+0,00/1 0,1} Kd5
{+0,05/12 1,4} 50. Rb8 {+0,00/1 0,1} Ke5 {+0,05/12 1,4} 51. Re8+
{+0,00/1 0,1} Kf6 {+0,05/13 1,4} 52. Kh5 {+0,00/1 0,1} Kf5 {+0,05/13 1,4}
53. Kh6 {+0,00/1 0,1} Rg1 {+0,05/11 1,5} 54. Re3 {+0,00/1 0,1} Rg6+
{+0,05/12 1,4} 55. Kh5 {+0,00/1 0,2} Rg8 {+0,05/13 1,4} 56. Kh6
{+0,00/1 0,1} Rg1 {+0,05/12 1,2} 57. Rf3+ {+0,00/1 0,2} Ke4 {+0,05/13 1,4}
58. Rf6 {+0,00/1 1,4} Kd5 {+0,05/12 1,4} 59. Rf5+ {+0,00/1 1:10} Ke6
{+0,05/13 42} 60. Rf4 {+0,00/1 0,1} Rg2 {+0,09/2 0,1} 61. Rd4 {+0,00/1 0,1}
Kf6 {+0,10/2 0,1} 62. Rh4 {+0,00/1 0,1} Rg6+ {+0,19/2 0,2} 63. Kh7
{+0,00/1 0,2} Rg7+ {+0,19/2 0,1} 64. Kh6 {+0,00/1 0,1} Rg2 {+0,14/2 0,1}
65. Kh7 {+0,00/1 0,2} Ke5 {+0,15/2 0,1} 66. Kh6 {+0,00/1 0,1} Rc2
{+0,19/2 0,1} 67. Rh5+ {+0,00/1 0,2} Ke4 {+0,17/2 0,1} 68. Rh1
{+0,00/1 0,1} Rc6+ {+0,19/2 0,2} 69. Kh5 {+0,00/1 0,2} Rc5+ {+0,16/2 0,1}
70. Kh6 {+0,00/1 0,1} Rc7 {+0,08/2 0,1} 71. Kg5 {+0,00/1 0,1} Rc3
{+0,05/2 0,1} 72. Rd1 {+0,00/1 0,2} Rg3+ {+0,05/2 0,2} 73. Kf6
{+0,00/1 0,2} Rf3+ {+0,08/2 0,1} 74. Ke7 {+0,00/1 0,1} Re3 {+0,00/3 0,1}
75. Rh1 {+0,00/1 0,1}
{Draw by fifty-move rule} 1/2-1/2
-Max