Author: Robert Hyatt
Date: 21:32:41 01/06/02
Go up one level in this thread
On January 06, 2002 at 19:30:58, Michael Fuhrmann wrote: >This position arose in a game on my comp between Crafty 18.12 and Yace 99.56: > >[D] 8/r7/P3Q3/4p1k1/3bKp2/8/8/8 b - - 0 99 > >Crafty played Kh4. It was the losing move. Log file of game shows Crafty thinks >this move draws. > >White(99): time 31896 >time remaining: 5:18 (crafty). >White(99): otim 36390 >time remaining: 6:03 (opponent). >White(99): Qe6 > time used: 17.22 > time surplus 0.00 time limit 14.49 (1:34) > nss depth time score variation (1) > 10-> 1.05 0.00 99. ... Kh4 100. Kf3 Kh5 101. Qf5+ > Kh6 102. Qf6+ Kh7 103. Qf5+ Kh6 > 11 1.85 0.00 99. ... Kh4 100. Kf3 Kh5 101. Qf5+ > Kh6 102. Qf6+ Kh7 103. Qf5+ Kh6 > 11-> 2.46 0.00 99. ... Kh4 100. Kf3 Kh5 101. Qf5+ > Kh6 102. Qf6+ Kh7 103. Qf5+ Kh6 > 12 5.03 0.00 99. ... Kh4 100. Kf3 Kh5 101. Qf5+ > Kh6 102. Qf6+ Kh7 103. Qf5+ Kh6 > 12-> 5.73 0.00 99. ... Kh4 100. Kf3 Kh5 101. Qf5+ > Kh6 102. Qf6+ Kh7 103. Qf5+ Kh6 > 13 12.26 0.00 99. ... Kh4 100. Kf3 Kh5 101. Qf5+ > Kh6 102. Qf6+ Kh7 103. Qf5+ Kh6 > 13-> 13.99 0.00 99. ... Kh4 100. Kf3 Kh5 101. Qf5+ > Kh6 102. Qf6+ Kh7 103. Qf5+ Kh6 > time=15.54 cpu=98% mat=0 n=3153431 fh=91% nps=202k > ext-> chk=277624 cap=399 pp=20672 1rep=9469 mate=637 > predicted=11 nodes=3153431 evals=572157 > endgame tablebase-> probes done=0 successful=0 > hashing-> trans/ref=60% pawn=99% used=39% >Black(99): Kh4 > time used: 15.54 > > >I let Crafty analyze this position after the game. And was surprised that at no >time did Crafty want to play Kh4, the move it played in the game. Here's log of >analysis: > >end-game phase > clearing hash tables > time surplus 0.00 time limit 30.00 (3:30) > nss depth time score variation (1) > 7 0.96 -0.26 1. ... Rc7 2. Qf5+ Kh4 3. Qf6+ Kg3 > 4. Qg5+ Kf2 5. Qh4+ Kf1 6. Qh3+ Ke2 > 7. Qf3+ Kd2 > 7-> 1.24 -0.26 1. ... Rc7 2. Qf5+ Kh4 3. Qf6+ Kg3 > 4. Qg5+ Kf2 5. Qh4+ Kf1 6. Qh3+ Ke2 > 7. Qf3+ Kd2 > 8 2.09 -0.22 1. ... Rc7 2. Qg8+ Kf6 3. Qd8+ Re7 > 4. Qh8+ Kg6 5. Qg8+ Rg7 6. Qe6+ Kg5 > 7. Qf5+ Kh4 8. Kd5 > 8-> 2.62 -0.22 1. ... Rc7 2. Qg8+ Kf6 3. Qd8+ Re7 > 4. Qh8+ Kg6 5. Qg8+ Rg7 6. Qe6+ Kg5 > 7. Qf5+ Kh4 8. Kd5 > 9 3.34 -0.22 1. ... Rc7 2. Qg8+ Kf6 3. Qd8+ Re7 > 4. Qd6+ Kf7 5. Kf5 Ra7 6. Qg6+ Ke7 > 7. Qe6+ Kd8 8. Ke4 > 9-> 3.98 -0.22 1. ... Rc7 2. Qg8+ Kf6 3. Qd8+ Re7 > 4. Qd6+ Kf7 5. Kf5 Ra7 6. Qg6+ Ke7 > 7. Qe6+ Kd8 8. Ke4 > 10 7.47 -0.12 1. ... Rc7 2. Qg8+ Kf6 3. Qh8+ Ke6 > 4. Qe8+ Kd6 5. Qf8+ Re7 6. Qb8+ Kc6 > 7. Qa8+ Kb5 8. Qd5+ Bc5 9. Qd3+ Kc6 > <HT> > 10-> 9.56 -0.12 1. ... Rc7 2. Qg8+ Kf6 3. Qh8+ Ke6 > 4. Qe8+ Kd6 5. Qf8+ Re7 6. Qb8+ Kc6 > 7. Qa8+ Kb5 8. Qd5+ Bc5 9. Qd3+ Kc6 > <HT> > 11 14.08 -0.09 1. ... Rc7 2. Qg8+ Kf6 3. Qh8+ Ke6 > 4. Qe8+ Kd6 5. Qf8+ Re7 6. Qh6+ Kc7 > 7. Qf6 Rd7 8. a7 Kb7 9. Qe6 Rd8 > 11-> 15.47 -0.09 1. ... Rc7 2. Qg8+ Kf6 3. Qh8+ Ke6 > 4. Qe8+ Kd6 5. Qf8+ Re7 6. Qh6+ Kc7 > 7. Qf6 Rd7 8. a7 Kb7 9. Qe6 Rd8 > 12 33.35 0.00 1. ... Rc7 2. Qd6 Ra7 3. Qe6 >Black(0): quit >execution complete. > >So my question is, why did crafty play Kh4 in the game (thinking it draws), when >during analysis it understands that Rc7 is much better? Crafty behaves slightly differently in analysis mode and in game mode, as in analysis mode some asymmetry is disabled while in game mode it is not. Rc7 isn't "much better" it is .2 better...
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.