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Subject: Re: Endgame Position : Is this a win for Black or a draw?

Author: John Merlino

Date: 09:16:29 01/04/03

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On January 04, 2003 at 10:58:00, Roy Brunjes wrote:

>
>I have been studying the following position, with the help of various programs,
>and I am not sure if this is a win for Black.  This position was declared a win
>for Black by some training software I am using.  The commentator there says that
>after:
>
> 1. Kg3     Kc2
> 2. Kxh3    Kxb2
> 3. Kh4     Kxa2
>
>    "White needs 8 moves to queen and Black needs only 4"
>
>The commentator then goes on to say that if instead of 1. Kg3, white tries 1.
>b4, that 1. ... Kc4! follows and the game is over.
>
>However, as you can see from the pgn I post below, after I forced the first move
>on each side (1. Kg3 Kc2) Chess Tiger 14 plays 2. b4 and the game seems to be a
>much tougher win for Black, if indeed a win still exists.  Odd how the
>commentator sees 1. b4  but not the possiblity of 2. b4 after the Black King has
>gone too far "south" to provide the same defense it could a move earlier.  By
>the way, Tiger wanted to play 1... Ke3 instead of 1. ... Kc2.  Given a bit more
>time, Tiger switches to Ke2 with the following played in the 30+30 shootout I am
>running: 1. Kg3 Ke2 2. a3 h2 3. Kxh2 Kxf3 4. Kg1 Kxf4 and the eval is hugely in
>Black's favor.  So it would appear that 1. ... Ke2 is superior to the
>commentator's suggested 1. ... Kc2.
>
>I post below the analysis of Chess Tiger 14 (48 MB hash) generated by the H8 GUI
>option "shootout" with a time control of 10 minutes + 15 seconds per move
>increment on my 1.6 GHz laptop.  Tiger seemed to average about 20-25 seconds per
>move at this time control.
>
>Tiger is a respectable endgame player and it can only see a draw after many
>moves.  Is Tiger right?  I am running the shootout again, this time with 30
>minutes + 30 seconds per move increment to see if additional time makes any
>difference in the result.
>
>Here is the diagram ...
>
>[D] 8/8/6p1/1p3p2/5P2/3k1P1p/PP3K2/8 w
>
>And here is the 10+15 shootout output from Chess Tiger 14.0 on my P4 1.6 GHz
>laptop using 48 MB for hash:
>
>1. Kg3 Kc2 2. b4 Kd3 3. a4 bxa4 4. b5 a3 5. b6 a2 6. b7 a1=Q 7. b8=Q Qe1+ 8.
>Kxh3 Ke3 9. Qe5+ Kf2 10. Kh4 Qh1+ 11. Kg5 Qh5+ 12. Kf6 Kxf3 13. Qd6 Qg4 14. Qd2
>Qxf4 15. Qd1+ Kg2 16. Qc2+ Qf2 17. Qc6+ Kh2 18. Qb7 g5 19. Kxg5 f4 20. Qh7+ Kg2
>21. Qe4+ f3 22. Kf6 Qb2+ 23. Kf5 Qe2 24. Qg4+ Kf1 25. Kf4 f2 26. Qg6 Qc4+ 27.
>Kg3 Qc3+ 28. Kh2 Qc7+ 29. Kh3 Qc8+ 30. Kg3 Qb8+ 31. Kh3 Qh8+ 32. Kg3 Qe5+ 33.
>Kh3 Qe3+ 34. Kh2 Qf4+ 35. Kh3 Qf3+ 36. Kh2 Qd5 37. Qb1+ Ke2 38. Qb2+ Qd2 39.
>Qe5+ Qe3 40. Qb2+ Ke1 41. Qb1+ Kd2 42. Qa2+ 1/2-1/2
>
>It appears to me that the commentator missed an important continuation for both
>sides:
>
>    A.   1. ... Ke2 appears superior to 1. ... Kc2
>    B.   After 1. Kg2 Kc2 it appears that 2. b4! draws
>
>What do you folks think?  What do your programs think?  Thanks for your help!
>
>Roy

First of all, Chessmaster 9000, on a P3-733, agrees with Fritz and you on point
'A' above:

Time	Depth	Score	Positions	Moves
0:00	5/9	-2.27	12203		1.Kg3 Ke3 2.b4 h2 3.Kxh2 Kxf3 4.a4
					bxa4 5.b5 Ke4 6.b6
0:00	6/10	-2.41	17989		1.Kg3 Ke3 2.b4 h2 3.Kxh2 Kxf3 4.a4
					bxa4 5.b5 Ke4 6.b6 a3
0:00	7/11	-2.14	54403		1.Kg3 Ke3 2.a3 h2 3.Kg2 h1=Q+ 4.Kxh1
					Kxf3 5.b3 Kxf4 6.a4 bxa4 7.bxa4
					Ke4 8.Kg2 g5 9.a5
0:00	8/12	-2.04	87346		1.Kg3 Ke3 2.a3 h2 3.Kg2 Kxf4 4.b3
					h1=Q+ 5.Kxh1 Kxf3 6.a4 bxa4 7.bxa4
					f4 8.a5 Ke2 9.a6 f3
0:00	9/13	-1.98	135130		1.Kg3 Ke3 2.a3 h2 3.Kg2 Kxf4 4.b3
					h1=Q+ 5.Kxh1 Kxf3 6.a4 bxa4 7.bxa4
					f4 8.a5 Ke2 9.a6 f3 10.a7
0:01	10/14	-1.67	228580		1.Kg3 Ke3 2.a3 h2 3.Kg2 Kxf4 4.b3
					h1=Q+ 5.Kxh1 Kxf3 6.a4 bxa4 7.bxa4
					Ke4 8.a5 Kd5 9.Kg2 g5 10.a6
0:02	11/15	-1.62	397115		1.Kg3 Ke3 2.a3 h2 3.Kxh2 Kxf3 4.b3
					Kxf4 5.a4 bxa4 6.bxa4 Ke5 7.a5
					Kd6 8.Kg3 g5 9.a6
0:04	12/16	-1.26	596393		1.Kg3 Ke3 2.a3 h2 3.Kxh2 Kxf3 4.b3
					Kxf4 5.a4 bxa4 6.bxa4 Ke5 7.a5
					Kd6 8.a6 Kc6 9.Kg3 g5 10.a7
0:07	13/17	-2.81	971409		1.Kg3 Ke3 2.a3 h2 3.Kxh2 Kxf3 4.b3
					Kxf4 5.a4 bxa4 6.bxa4 Ke5 7.a5
					Kd6 8.a6 Kc6 9.Kg3 Kb6 10.a7 Kxa7
					11.Kf4
0:14	14/18	-2.84	1711580		1.Kg3 Ke3 2.a3 h2 3.Kxh2 Kxf3 4.b3
					Kxf4 5.a4 bxa4 6.bxa4 Ke5 7.a5
					Kd6 8.a6 Kc6 9.Kg3 Kb6 10.Kf4 Kxa6
0:30	15/19	-3.05	3425601		1.Kg3 Ke3 2.a3 h2 3.Kxh2 Kxf3 4.b3
					Kxf4 5.a4 bxa4 6.bxa4 Ke5 7.a5
					Kd6 8.a6 Kc6 9.Kg3 Kb6 10.Kf4 Kxa6
					11.Ke5 Kb5
1:01	16/20	-3.05	6656237		1.Kg3 Ke3 2.a3 h2 3.Kxh2 Kxf3 4.b3
					Kxf4 5.a4 bxa4 6.bxa4 Ke5 7.a5
					Kd6 8.a6 Kc6 9.Kg3 Kb6 10.Kf4 Kxa6
					11.Ke5 Kb5

Secondly, after forcing 1.Kg3 Kc3 2.b4, it appears that all of the moves in your
Tiger game up to 8.Kxh3 appear to be forced. After forcing these moves in CM, it
appears to be a draw:

Time	Depth	Score	Positions	Moves
0:00	1/3	-0.93	3132		8...Ke2 9.Qb3 Qf1+ 10.Kh4 Qxf3
0:00	1/4	-0.93	8414		8...Ke2 9.Qb3 Qf1+ 10.Kh4 Qxf3
0:00	1/5	-1.08	40294		8...Ke2 9.Qb3 Qd4 10.Qb8 Kxf3
0:00	1/6	-1.29	60035		8...Ke2 9.Qb3 Qd4 10.Qb7 Qxf4 11.Kg2
					Qe3
0:01	1/7	-1.75	110250		8...Ke2 9.Qb3 Qh1+ 10.Kg3 Qe1+
					11.Kh3 Kf2 12.Qb2+ Kxf3 13.Qh2
					Qf2 14.Qxf2+ Kxf2
0:02	2/8	0.00	243553		8...Ke2 9.Qb5+ Kxf3 10.Qc6+ Kxf4
					11.Qd6+ Ke4 12.Qe6+ Kd3 13.Qb3+
					Ke2 14.Qa2+ Kf3 15.Qd5+ Kf2 16.Qd4+
					Kf1 17.Qa1+ Kf2 18.Qd4+
0:05	2/8	-0.17	498248		8...Qh1+ 9.Kg3 Qe1+ 10.Kg2 Qe3
					11.Kg3 Qd4 12.Qb3+ Kd2 13.Qa2+
					Kc1 14.Qe2 Qg1+ 15.Kh4
0:10	3/9	-0.14	976827		8...Qh1+ 9.Kg3 Qe1+ 10.Kg2 Qe3
					11.Kg3 Qd4 12.Qb3+ Kd2 13.Qa2+
					Kc1 14.Qe2 Qd2 15.Qf1+ Kb2 16.Qc4
0:17	4/10	-0.14	1717672		8...Qh1+ 9.Kg3 Qe1+ 10.Kg2 Qe3
					11.Kg3 Qd4 12.Qb3+ Kd2 13.Qa2+
					Kc1 14.Qa3+ Kd1 15.Qb3+ Ke1 16.Qb1+
					Qd1 17.Qb6 Qd2 18.Qg1+ Ke2
0:35	5/11	-0.10	3613809		8...Qh1+ 9.Kg3 Qe1+ 10.Kg2 Qe3
					11.Kg3 Qd4 12.Qb3+ Kd2 13.Qa2+
					Kc1 14.Qb3 Qg1+ 15.Kh3 Qh1+ 16.Kg3
					Qe1+ 17.Kh3 Kd2 18.Qb4+ Ke2 19.Qe7+
					Kf1
1:12	6/12	-0.08	7568648		8...Qh1+ 9.Kg3 Qe1+ 10.Kg2 Qe3
					11.Kg3 Qd4 12.Qb3+ Kd2 13.Qa2+
					Kc1 14.Qa3+ Kd1 15.Qb3+ Ke1 16.Qb1+
					Ke2 17.Qa2+ Qd2 18.Qa6+ Qd3 19.Qa2+
					Kd1

Looks like you should write your own book!

jm



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