SF misevaluates position, case #3095768

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tpoppins
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SF misevaluates position, case #3095768

Post by tpoppins »

[d]2b5/8/p1p2pk1/P1Pp1p1p/1P1P1P2/3B1P1K/8/8 w - - 0 201

This is the final position from a game in a recently completed 40/40 test. The game was adjudicated as a draw on the 200th move. Hard to see how White could make progress here, yet recent SF dev builds give around +1.38 up to depth=90 with 6-men Syzygy.
Tirsa Poppins
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zullil
Posts: 6442
Joined: Tue Jan 09, 2007 12:31 am
Location: PA USA
Full name: Louis Zulli

Re: SF misevaluates position, case #3095768

Post by zullil »

tpoppins wrote: ↑Tue Mar 26, 2019 12:26 pm [d]2b5/8/p1p2pk1/P1Pp1p1p/1P1P1P2/3B1P1K/8/8 w - - 0 201

This is the final position from a game in a recently completed 40/40 test. The game was adjudicated as a draw on the 200th move. Hard to see how White could make progress here, yet recent SF dev builds give around +1.38 up to depth=90 with 6-men Syzygy.
Here's the static evaluation of the position, from Stockfish-dev:

Code: Select all

Stockfish 260319 64 POPCNT by T. Romstad, M. Costalba, J. Kiiski, G. Linscott
position fen 2b5/8/p1p2pk1/P1Pp1p1p/1P1P1P2/3B1P1K/8/8 w - - 0 201
d

 +---+---+---+---+---+---+---+---+
 |   |   | b |   |   |   |   |   |
 +---+---+---+---+---+---+---+---+
 |   |   |   |   |   |   |   |   |
 +---+---+---+---+---+---+---+---+
 | p |   | p |   |   | p | k |   |
 +---+---+---+---+---+---+---+---+
 | P |   | P | p |   | p |   | p |
 +---+---+---+---+---+---+---+---+
 |   | P |   | P |   | P |   |   |
 +---+---+---+---+---+---+---+---+
 |   |   |   | B |   | P |   | K |
 +---+---+---+---+---+---+---+---+
 |   |   |   |   |   |   |   |   |
 +---+---+---+---+---+---+---+---+
 |   |   |   |   |   |   |   |   |
 +---+---+---+---+---+---+---+---+

Fen: 2b5/8/p1p2pk1/P1Pp1p1p/1P1P1P2/3B1P1K/8/8 w - - 0 201
Key: 64BEA45E869E80BE
Checkers: 
eval
     Term    |    White    |    Black    |    Total   
             |   MG    EG  |   MG    EG  |   MG    EG 
 ------------+-------------+-------------+------------
    Material |  ----  ---- |  ----  ---- | -0.18  0.12
   Imbalance |  ----  ---- |  ----  ---- |  0.00  0.00
       Pawns |  0.36 -0.36 | -0.07 -0.63 |  0.42  0.27
     Knights |  0.00  0.00 |  0.00  0.00 |  0.00  0.00
     Bishops | -0.08 -0.29 | -0.48 -0.97 |  0.41  0.69
       Rooks |  0.00  0.00 |  0.00  0.00 |  0.00  0.00
      Queens |  0.00  0.00 |  0.00  0.00 |  0.00  0.00
    Mobility |  0.26  0.25 |  0.12  0.06 |  0.14  0.19
 King safety | -0.83 -0.15 | -0.76 -0.08 | -0.08 -0.08
     Threats |  0.03  0.18 |  0.13  0.13 | -0.10  0.05
      Passed |  0.00  0.00 |  0.04  0.15 | -0.04 -0.15
       Space |  0.00  0.00 |  0.00  0.00 |  0.00  0.00
  Initiative |  ----  ---- |  ----  ---- |  0.00  0.18
 ------------+-------------+-------------+------------
       Total |  ----  ---- |  ----  ---- |  0.57  1.26

Total evaluation: 1.39 (white side)
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MikeB
Posts: 4889
Joined: Thu Mar 09, 2006 6:34 am
Location: Pen Argyl, Pennsylvania

Re: SF misevaluates position, case #3095768

Post by MikeB »

tpoppins wrote: ↑Tue Mar 26, 2019 12:26 pm [d]2b5/8/p1p2pk1/P1Pp1p1p/1P1P1P2/3B1P1K/8/8 w - - 0 201

This is the final position from a game in a recently completed 40/40 test. The game was adjudicated as a draw on the 200th move. Hard to see how White could make progress here, yet recent SF dev builds give around +1.38 up to depth=90 with 6-men Syzygy.
This is what near release McCain X2 thinks after a minute plus of thinking:

Code: Select all

dep	score	nodes	time	(not shown:  tbhits	knps	seldep)
 52	+0.31 	1.83G	0:49.25	Bf1 Kg7 Kh2 Bb7 Bd3 Bc8 Be2 Kg6 Kg2 Kf7 Kh3 Kg6 Bd3 Kh7 Kg2 Kg6 Bb1 Kf7 Bc2 Kg6 Kf2 Kf7 Ke3 Bd7 Bd3 Bc8 Be2 Kg7 Bd1 Kf7 Ba4 Bb7 Kf2 Kg6 Kg3 Kg7 Bb3 Kf7 Bc2 Bc8 Kh3 Kg6 Kh4 Be6 b5 cxb5 c6 b4 c7 Kf7 Kxh5 Bd7 Bb3 Ke7 Kg6 Bc8 Ba2 
 51	+0.31 	1.83G	0:49.12	Bf1 Kg7 Kh2 Bb7 Bd3 Bc8 Be2 Kg6 Kg2 Kf7 Kf1 Kg6 Bd1 Kf7 Ba4 Bd7 Kf2 Kg6 Bb3 Bc8 Bc2 Bb7 Kg2 Bc8 Kh3 Kg7 Bb3 Kh6 Kg2 Kg7 Ba4 Bd7 Bd1 Kf7 Bc2 Kg6 Bb3 Be6 b5 cxb5 Kg3 Kg7 Kh4 Bf7 c6 Kf8 c7 Be6 Kxh5 Ke7 Kg6 Bc8 Kg7 b4 Ba4 Bd7 Bd1 Kd 
 50	+0.31 	1.66G	0:44.60	Bf1 Kg7 Kh2 Bb7 Kg2 Bc8 Kh3 Bb7 Bd3 Bc8 Kh4 Kg6 Bb1 Bd7 Kg3 Bc8 Kg2 Kf7 Bd3 Kg6 Kf2 Kg7 Bc2 Kf7 Kf1 Bd7 Ba4 Kg6 Kg1 Kf7 Kh1 Kf8 Kg2 Kg7 Kg3 Kg6 Kh3 Kg7 Bc2 Kh6 Bb3 Bc8 b5 axb5 Kh4 Kg6 Bc2 Bb7 Bd3 Ba6 
 50	+0.38!	1.59G	0:42.47	Bf1! 
 49	+0.31 	1.56G	0:41.57	Bf1 Kg7 Kh2 Kg6 Kg2 Kg7 Kh3 Kg6 Bd3 Bb7 Kg3 Bc8 Kf2 Bb7 Kg1 Bc8 Bc2 Bd7 Kg2 Be6 Ba4 Bd7 Kh3 Kg7 Bc2 Kg6 Bd1 Bc8 Ba4 Bb7 Kg3 Kg7 Bc2 Kg6 Kh4 Bc8 Bb1 Bd7 Kg3 Be6 b5 cxb5 c6 Kf7 Bd3 Bc8 Kh4 Ke6 Kxh5 Kd6 Kg6 b4 
 49	+0.38!	1.54G	0:41.21	Bf1! 
 48	+0.31 	1.50G	0:39.96	Bf1 Kg7 Kh2 Kf7 Bd3 Kg6 Be2 Bb7 Bf1 Bc8 Kg3 Bb7 Bh3 Bc8 Kh4 Bb7 Bg2 Kh6 Kg3 Kg6 Bf1 Bc8 Be2 Kh6 Kh3 Kg6 Bd1 Bd7 Bb3 Bc8 Ba4 Bb7 Bc2 Bc8 Kh4 Bd7 Ba4 Kh6 Kg3 Kg6 Kg2 Kh6 Bb3 Be6 b5 cxb5 c6 Kg7 c7 Bc8 Kh3 Kf7 Kh4 Ke6 Kxh5 b4 
 48	+0.38!	1.42G	0:37.60	Bf1! 
 47	+0.31 	1.39G	0:36.52	Bf1 Kg7 Kh2 Kf7 Bd3 Kg6 Kg3 Kh6 Kh4 Kg6 Bf1 Bb7 Kh3 Bc8 Be2 Kg7 Kh4 Kg6 Bd3 Kh6 Bf1 Bb7 Kg3 Kg6 Bd3 Bc8 Bc2 Bb7 Kh3 Bc8 Bb1 Bd7 Kg3 Be6 b5 cxb5 Ba2 Kf7 Kh4 Ke7 Kxh5 b4 Bb1 Bf7+ Kh4 Be8 Bd3 Ba4 Bxa6 Bc2 Bb7 
 47	+0.38!	1.37G	0:35.82	Bf1! 
 46	+0.38!	1.34G	0:34.91	Bf1! 
 46	+0.31?	1.32G	0:34.50	Bf1 Kg7? 
 45	+0.38 	847.1M	0:22.17	Bf1 Kg7 Bd3 Kh6 Bc2 Kg7 Ba4 Bd7 Bd1 Kg6 Kg2 Kf7 Be2 Bc8 Kf2 Kg7 Bd3 Kg6 Kg3 Kh7 Kh4 Kg6 Bc2 Bd7 Bb3 Be6 b5 cxb5 c6 Kg7 Ba2 Kf7 Kxh5 Ke7 Kg6 b4 Kg7 Bc8 c7 Kd7 Kxf6 Kd6 Bb3 Bd7 Bd1 Be6 Bc2 Bd7 Bxf5 Bxf5 Kxf5 Kxc7 Ke5 b3 
 44	+0.38?	790.1M	0:20.63	Bf1 Kg7? 
 44	+0.44?	133.6M	0:03.58	Bf1 Kg7? 
 43	+0.50 	59.7M  	0:01.67	Bf1 Kg7 Kh4 Kg6 Bd3 Bb7 Kg3 Bc8 Kg2 Kg7 Bc2 Kg6 Ba4 Bb7 Kh2 Kf7 Kg3 Kg6 Kh4 Kh6 Bb3 Kg6 Kh3 Kh6 Bc2 Kg6 Bd1 Bc8 Kg3 Bd7 Ba4 Kg7 Kh2 Kg6 Bb3 Be6 Kh3 Kg7 Kh4 Kh6 b5 cxb5 c6 Kg7 Kxh5 
 42	+0.50 	57.9M  	0:01.62	Bf1 Kg7 Kh4 Kg6 Bd3 Bb7 Bb1 Bc8 Bc2 Bb7 Kh3 Bc8 Ba4 Bb7 Kh2 Kf7 Kg2 Kg6 Bb3 Bc8 Kg3 Kf7 Bd1 Kg6 Ba4 Bd7 Kh2 Kf7 Kh3 Kg7 Bb3 Be6 Kh4 Kh6 b5 cxb5 c6 Kg7 Kxh5 Bf7+ Kh4 Kf8 c7 Be6 Bxd5 Bc8 Ba2 Ke7 Kh5 Kd6 Kg6 
 41	+0.56 	39.2M  	0:01.12	Bf1 Kg7 Kg3 Kg6 Be2 Kh7 Kh4 Kg6 Kh3 Bb7 Kg2 Kh6 Bd1 Kg7 Kg3 Kg6 Bb3 Bc8 Kh3 Kf7 Bd1 Kg6 Ba4 Bd7 Kh4 Kh6 Kg3 Kg7 Bb3 Be6 Bc2 Kh6 b5 cxb5 c6 Kg6 Bd3 h4+ Kh3 Bc8 Kxh4 Kf7 Kh5 Ke7 Kg6 
 40	+0.56 	38.2M  	0:01.08	Bf1 Kg7 Kh4 Kg6 Bd3 Bb7 Kg3 Bc8 Kh3 Kh6 Be2 Kg7 Kh4 Kg6 Bf1 Bb7 Bh3 Bc8 Kg3 Kh7 Kh2 Kg7 Kg1 Kf7 Bf1 Kg6 Bd3 Kf7 Kg2 Kg7 Bc2 Kg6 Kh3 Kh6 Ba4 Bd7 Kh4 Kg6 Bd1 Be6 
 39	+0.50 	31.6M  	0:00.89	Bf1 Kh6 Kg2 Kg6 Be2 Kg7 Kh3 Kh6 Kh2 Kg6 Kg1 Kg7 Bd3 Kf7 Kf2 Kg6 Kg3 Kf7 Bc2 Kg6 Kh3 Bb7 Kh2 Bc8 Ba4 Bd7 Kg3 Kf7 Kh3 Kg7 Bd1 Bc8 Bb3 Bb7 Kh4 Kg6 Ba4 Kh6 Bd1 Bc8 Kh3 
 38	+0.50 	28.6M  	0:00.81	Bf1 Kg7 Kh4 Kh6 Be2 Bb7 Kh3 Bc8 Bd3 Kg6 Kh4 Bb7 Bc2 Bc8 Bb3 Be6 Kg3 Kf7 Kh3 Bc8 Kh4 Kg6 Bc2 Bd7 Ba4 Kh6 Kg3 Kg7 Bd1 Bc8 Kh3 Kg6 Ba4 Bb7 Kh4 Kh6 Bb3 Bc8 
 37	+0.50 	22.9M  	0:00.64	Bf1 Kg7 Kh4 Kh6 Be2 Kg6 Bd3 Bb7 Kh3 Bc8 Kh2 Kh7 Kg2 Kh6 Be2 Kg7 Bd1 Kg6 Ba4 Bd7 Kh3 Kh6 Bb3 Bc8 Kg3 Kg7 Bd1 Kh6 Ba4 Bd7 Bb3 Be6 b5 cxb5 c6 Kg6 c7 Kg7 Kh4 Bc8 Bxd5 Kf8 Kxh5 Ke7 Kg6 
 36	+0.56 	14.2M  	0:00.40	Bf1 Bb7 Be2 Bc8 Kh4 Bb7 Bd1 Bc8 Kg3 Bd7 Bb3 Bc8 Kg2 Kh6 Kh3 Kg6 Ba4 Bd7 Kg2 Kh6 Bc2 Bc8 Kh2 Kg6 Ba4 Bb7 Kg3 Kg7 Kf2 Kf7 Bc2 Kg6 Bd3 Bc8 Ke3 Kf7 Bb1 
 35	+0.56 	9.82M  	0:00.28	Bf1 Bb7 Be2 Kh6 Kh4 Bc8 Bd1 Bb7 Bc2 Bc8 Ba4 Bd7 Bd1 Kg6 Bb3 Bc8 Kg3 Be6 Ba4 Bd7 Kh3 Kh6 Bd1 Bc8 Kg3 Bb7 Bb3 Kh7 Kh3 Kg6 Bc2 Ba8 Bd3 Bb7 
 34	+0.69 	2.93M  	0:00.09	Bf1 Kh6 Be2 Bb7 Kh4 Kg6 Bd1 Bc8 Ba4 Bb7 Bc2 Bc8 Bd3 Bb7 Kg3 Bc8 Kh3 Bb7 Kg2 Bc8 Kg1 Bb7 Kf2 Bc8 Be2 Kh6 Kg3 Kg6 Kh3 Kh6 Bd1 Kg6 Ba4 Bd7 Kh4 Kh6 
 33	+0.69 	2.05M  	0:00.06	Bf1 Kh6 Be2 Bb7 Kh4 Kg6 Bd1 Bc8 Ba4 Bd7 Kg3 Kh7 Bc2 Kg6 Kg2 Bc8 Bd3 Bb7 Bf1 Bc8 Be2 Bb7 Bd3 Bc8 Bf1 Bb7 Kh3 Bc8 Be2 Kh6 Kh4 Kg6 Kg3 
 32	+0.69 	1.84M  	0:00.06	Bf1 Kh6 Be2 Bb7 Kh4 Kg6 Kg3 Bc8 Bd3 Kh6 Kg2 Kg7 Bf1 Kh6 Kh3 Kg6 Kh4 Kh6 Be2 Kg6 Bd1 Kh6 Bc2 Kg6 Kg3 Bd7 Kg2 Bc8 Ba4 Bd7 Kh3 Kh6 Bc2 Kg6 
 31	+0.69 	1.70M  	0:00.05	Bf1 Kh6 Be2 Kg6 Bd1 Kh6 Kh4 Kg6 Ba4 Bd7 Kg3 Kh7 Bc2 Kh6 Bb1 Kh7 Bd3 Bc8 Bc2 Kg6 Kh3 Bb7 Kh4 Bc8 Kg3 Kh6 Ba4 Bd7 Kh3 Kg6 Kh4 Kh6 Bd1 
 30	+0.69 	1.51M  	0:00.05	Bf1 Kh6 Bd3 Kg6 Kg3 Kh6 Kg2 Kg7 Bf1 Kh6 Kh3 Kg6 Kh4 Bb7 Kg3 Kh7 Bd3 Kg6 Bc2 Bc8 Ba4 Bd7 Bb3 Bc8 Kh4 Kh6 Kh3 Kg6 Ba4 Bd7 Kg3 Kh6 
 29	+0.69 	1.46M  	0:00.04	Bf1 Kh6 Bd3 Kg6 Kg3 Kh6 Kg2 Kg7 Bf1 Kh6 Kh3 Kg6 Kh4 Bb7 Kg3 Bc8 Be2 Kh6 Bd3 Kg6 Bc2 Bd7 Kh3 Bc8 Kh4 Bd7 Bb3 Bc8 Kg3 Kh7 Bd1 
 28	+0.69 	1.43M  	0:00.04	Bf1 Kh6 Bd3 Kg6 Kg3 Kh6 Kg2 Kg7 Bf1 Kh6 Kh3 Kg6 Kh4 Bb7 Bd3 Bc8 Bc2 Bd7 Kg3 Kh6 Kg2 Kg6 Bd3 Bc8 Kf2 Kh6 Kg3 Kg6 Bc2 Kh6 
 27	+0.69 	1.39M  	0:00.04	Bf1 Kh6 Bd3 Kg6 Be2 Kh6 Kh4 Kg6 Bf1 Bb7 Bd3 Bc8 Bc2 Kh6 Kg3 Kg6 Kg2 Bd7 Bd1 Kh6 Kh3 Kg6 Bb3 Bc8 Ba4 Bd7 Bd1 Bc8 
 26	+0.75 	903578	0:00.03	Bf1 Kh6 Bd3 Kg6 Kh4 Bb7 Be2 Bc8 Kg3 Kh6 Bd3 Kg6 Kh3 Bb7 Kh4 Bc8 Bc2 Kh6 Kh3 Bd7 Bd3 Bc8 Kh2 Kg6 Bf1 Bb7 
 25	+0.75 	476965	0:00.02	Bf1 Kh6 Bd3 Kg7 Kh4 Kg6 Be2 Bb7 Kh3 Bc8 Bd1 Kh6 Ba4 Bd7 Kg3 Kg6 Bb3 Bc8 Bd1 Kh6 Be2 Kg6 Kh3 Bb7 Bd1 Bc8 
 24	+0.75 	374467	0:00.02	Bf1 Kh6 Bd3 Kg7 Kh4 Kg6 Be2 Bb7 Kh3 Bc8 Bd1 Kh6 Ba4 Bd7 Bc2 Bc8 Kh4 Bd7 Kg3 Bc8 Bb3 Kg6 Kh3 Kg7 Kh4 Kg6 
 23	+0.75 	347332	0:00.02	Bf1 Kh6 Bd3 Kg7 Kh4 Kg6 Be2 Bb7 Kh3 Bc8 Bd1 Kh6 Ba4 Bd7 Bc2 Bc8 Kh4 Bd7 Kg3 Bc8 Bb3 Kg6 Ba4 Bd7 Kh4 Kh6 
 22	+0.75 	319680	0:00.01	Bf1 Kh6 Bd3 Kg7 Kh4 Kg6 Be2 Bb7 Kh3 Bc8 Bd1 Kh6 Ba4 Bd7 Bc2 Bc8 Kg3 Kg6 Ba4 Bd7 Kh4 Kh6 
 21	+0.75 	282800	0:00.01	Bf1 Kh6 Bd3 Kg7 Kg3 Kh7 Bf1 Kh6 Be2 Bb7 Bd1 Bc8 Ba4 Bd7 Bc2 Kg6 Kh4 Kh6 Bb3 Bc8 Ba4 Bd7 Bc2 
 20	+0.75 	249485	0:00.01	Bf1 Kh6 Kh4 Kg6 Bd3 Kh6 Bb1 Kg6 Kg3 Bb7 Bc2 Bc8 Ba4 Bd7 Kh4 Kh6 Bb3 Bc8 Kg3 Kg6 Bc2 Be6 Bd3 Bc8 
 19	+0.75 	232904	0:00.01	Bf1 Kh6 Kh4 Kg6 Bd3 Kh6 Be2 Bb7 Bf1 Kg6 Kg3 Kh6 Bd3 Bc8 Bc2 Kg6 Ba4 Bd7 Kh4 Kh6 Bb3 Bc8 Kg3 Kg6 
 18	+0.75 	218779	0:00.01	Bf1 Kh6 Kh4 Kg6 Bd3 Kh6 Be2 Bb7 Bf1 Kg6 Kg3 Kh6 Bd3 Bc8 Bc2 Kg6 Ba4 Bd7 Kh4 
 17	+0.75 	205983	0:00.01	Bf1 Kh6 Kh4 Bb7 Be2 Kg6 Bd3 Bc8 Kh3 Kg7 Kg3 Kh7 Bb1 Kh6 Bc2 Kg6 Ba4 Bd7 
 16	+0.75 	184221	0:00.01	Bf1 Kh6 Be2 Kg6 Kh4 Bb7 Bd3 Bc8 Bf1 Bb7 Be2 Kh6 Bd1 Bc8 Bb3 Kg6 Ba4 
 15	+0.81 	143816	0:00.01	Bf1 Bb7 Be2 Bc8 Bd3 Bb7 Kh4 Bc8 Bf1 Bb7 Be2 Kh6 Bd1 Bc8 Bc2 Kg6 
 14	+0.81 	122615	0:00.01	Bf1 Bb7 Be2 Bc8 Kh4 Bb7 Bd1 Bc8 Kg3 Kf7 Be2 Kg6 Bd3 Kh7 
 13	+0.81 	112481	0:00.01	Bf1 Bb7 Be2 Bc8 Kh4 Bb7 Bd1 Bc8 Kg3 Kg7 Be2 Kg6 Kh3 
 12	+0.81 	104807	0:00.01	Bf1 Bb7 Be2 Bc8 Kh4 Bb7 Bd3 Bc8 Kg3 Kh7 
 11	+0.78 	86172  	0:00.01	Bf1 Bb7 Be2 Bc8 Bd3 Bb7 Kg3 Bc8 Kh4 Bb7 Be2 
 10	+0.90 	65081  	0:00.01	Bf1 Kh7 Bd3 Kg6 Kh4 Kh6 Be2 Kg6 Bf1 Bb7 
  9	+1.19 	30486  	0:00.01	Bf1 Bb7 Kh4 Bc8 Be2 Bb7 Bd3 
  8	+1.03 	23521  	0:00.01	Bf1 Bb7 Kh4 Kh6 Be2 Bc8 Bd3 Kg6 Be2 
  7	+1.09 	13182  	0:00.00	Kh4 Bb7 Be2 Bc8 Bf1 Bb7 Bh3 
  6	+1.03 	7753    	0:00.00	Kg3 Bb7 Kh4 Bc8 Bf1 
  5	+0.94 	5660    	0:00.00	Kg3 Bb7 Kh4 Bc8 Be2 
  4	+1.04 	3807    	0:00.00	Kg3 Bb7 Kh4 Bc8 
  3	+1.19 	2175    	0:00.00	Kg3 Bb7 Kh4 
  2	+1.19 	1471    	0:00.00	Kg3 Bb7 Kh4 
  1	+1.03 	369      	0:00.00	Kh4 
  1	Found 1511 tablebases 
  0	#
static eval

Code: Select all

Mac-Pro:src michaelbyrne$ McCain-X2
McCain X2 by M. Byrne and scores of others...
info string Could not open Carlsen
info string Could not open Champions
info string Could not open Cerebellum
position fen 2b5/8/p1p2pk1/P1Pp1p1p/1P1P1P2/3B1P1K/8/8 w - - 0 201
d

 +---+---+---+---+---+---+---+---+
 |   |   | b |   |   |   |   |   |
 +---+---+---+---+---+---+---+---+
 |   |   |   |   |   |   |   |   |
 +---+---+---+---+---+---+---+---+
 | p |   | p |   |   | p | k |   |
 +---+---+---+---+---+---+---+---+
 | P |   | P | p |   | p |   | p |
 +---+---+---+---+---+---+---+---+
 |   | P |   | P |   | P |   |   |
 +---+---+---+---+---+---+---+---+
 |   |   |   | B |   | P |   | K |
 +---+---+---+---+---+---+---+---+
 |   |   |   |   |   |   |   |   |
 +---+---+---+---+---+---+---+---+
 |   |   |   |   |   |   |   |   |
 +---+---+---+---+---+---+---+---+

Fen: 2b5/8/p1p2pk1/P1Pp1p1p/1P1P1P2/3B1P1K/8/8 w - - 0 201
Key: 64BEA45E869E80BE
Checkers: 
eval
     Term    |    White    |    Black    |    Total   
             |   MG    EG  |   MG    EG  |   MG    EG 
 ------------+-------------+-------------+------------
    Material |  ----  ---- |  ----  ---- | -0.10  0.14
   Imbalance |  ----  ---- |  ----  ---- |  0.00  0.00
       Pawns |  0.25 -0.41 | -0.08 -0.63 |  0.33  0.22
     Knights |  0.00  0.00 |  0.00  0.00 |  0.00  0.00
     Bishops | -0.08 -0.29 | -0.48 -0.97 |  0.41  0.69
       Rooks |  0.00  0.00 |  0.00  0.00 |  0.00  0.00
      Queens |  0.00  0.00 |  0.00  0.00 |  0.00  0.00
    Mobility |  0.25  0.23 |  0.12  0.08 |  0.13  0.16
 King safety | -0.80 -0.15 | -0.74 -0.08 | -0.06 -0.08
     Threats |  0.03  0.18 |  0.13  0.13 | -0.10  0.05
      Passed |  0.00  0.00 |  0.04  0.15 | -0.04 -0.15
       Space |  0.00  0.00 |  0.00  0.00 |  0.00  0.00
  Initiative |  ----  ---- |  ----  ---- |  0.00  0.09
 ------------+-------------+-------------+------------
       Total |  ----  ---- |  ----  ---- |  0.56  1.12

Total evaluation: 1.25 (white side)
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hgm
Posts: 27790
Joined: Fri Mar 10, 2006 10:06 am
Location: Amsterdam
Full name: H G Muller

Re: SF misevaluates position, case #3095768

Post by hgm »

I doubt if it would get a positive score when it would force the static eval of any position with the same Pawn structure and same material key to zero (or possibly contempt). Logically this is what it should always do: it doesn't matter how much ahead you think you are in the current position; if there is no way to reset the ply counter without losing that advantage, you will lose the advantage or will have a 50-move draw.
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