Computer Chess Club Archives


Search

Terms

Messages

Subject: Re: Computer Chess and Positional Judgement, IE Reduce and Simplify.

Author: Terry McCracken

Date: 17:02:13 01/06/03

Go up one level in this thread


Thanks to all who have replied.

I just tested this position with Rebel XP DOS and it found on my meager
hardware, PIII 500, Rd7+! after 4min. 16 sec.

Good Work Ed!

Terry



On January 06, 2003 at 18:28:05, Dieter Buerssner wrote:

>On January 06, 2003 at 03:20:32, Terry McCracken wrote:
>
>I pretty much agree with the comments of Pat.
>
>>This position arose in a casual game tonight. I played the "Human" Rd7+ to
>>quickly reduce it to a simple winning King & Pawn Ending.
>>
>>Computers like to keep it more complex with Rf6!?
>
>Mine, too - yes
>
>>How long will it take, if ever, for a top programme to find and play the "Human"
>>Rd7+, winning with simplicity?
>>
>>How much effort is put foward by the programmers, to tell the computer,
>>"Reduce & Simplify"?
>
>For me, it is not so easy. If one really could trust the pawn endgame evaluation
>function, it would be no problem. But I think, in general some analysis (=search
>depth) is needed. Actually Yace is slightly forced to simplyfy, and also tries
>to look closer at the pawn endgame. In this specific case, Rf6 for a long time
>just is a little bit ahead of Rd7+, so it doesn't help. Ed Schröder once
>mentioned here, that Rebel gives an additional bonus for a seemingly winning
>pawn endgame. With this trick, Rd7+ is found in no time. But it also has
>disadvantages - perhaps not so much in practical games.
>
>>8/p1r1k2p/2PR2p1/6P1/8/8/P4P1P/6K1 w
>
>After 12 minutes, finally Rd7+ is choosen.
>
>  18004216  18.686   1.85 15.  1. Rf6 Kd8 2. f4 Re7 3. Kf2 Kc7 4. Kf3 Kb6 5.
>                               h4 Kc5 6. a4 Kb4 7. h5 gxh5 8. Rh6 {80}
>  27161755  28.331   1.90 16t  1. Rf6 Kd8 2. f4 Re7 3. Kf2 Kc7 4. Kf3 Kb6 5.
>                               h4 Rc7 6. Ke4 Re7+ 7. Kd5 Re2 8. a3 {HT} {160}
>  30455741  31.650   1.90 16.  1. Rf6 Kd8 2. f4 Re7 3. Kf2 Kc7 4. Kf3 Kb6 5.
>                               h4 Rc7 6. Ke4 Re7+ 7. Kd5 Re2 8. a3 {HT} {160}
>  51283841  53.759   1.93 17t  1. Rf6 Kd8 2. f4 Re7 3. Kf2 Kc7 4. Kf3 Kb6 5.
>                               h4 Rc7 6. h5 gxh5 7. f5 a6 8. Rh6 {80}
>  53681012  56.289   1.93 17.  1. Rf6 Kd8 2. f4 Re7 3. Kf2 Kc7 4. Kf3 Kb6 5.
>                               h4 Rc7 6. h5 gxh5 7. f5 a6 8. Rh6 {80}
> 112074154  1:58.7   2.05 18t  1. Rf6 Kd8 2. Re6 Rf7 3. Kg2 {HT}
> 116677256  2:03.6   2.05 18.  1. Rf6 Kd8 2. Re6 Rf7 3. Kg2
> 243482328  4:19.7   2.04 19t  1. Rf6 Kd8 2. Kg2 Re7 3. f4 Re2+H 4. Kg3H Ke7H
>                               5. f5H gxf5H 6. Rxf5H Rxa2H 7. Rd5H Ke6H 8.
>                               Rd7H {HT} {80}
> 256365403  4:33.4   2.04 19.  1. Rf6 Kd8 2. Kg2 Re7 3. f4 Re2+ 4. Kg3 Ke7 5.
>                               f5 gxf5 6. Rxf5 Rxa2 7. Rd5 Ke6 8. Rd7 {HT} {80}
> 645780926 11:39.8   2.12 20t  1. Rf6 Kd8 2. f4 Re7 3. Kf2 Kc7H 4. h4H a5H 5.
>                               f5H gxf5H 6. Rxf5H Re4H 7. Rxa5H Rxh4H 8. a4H
>                               {HT} {160}
> 678125210 12:15.1   2.13 20t+ 1. Rd7+ Rxd7 2. cxd7 Kxd7 3. Kg2 Ke7 4. f4 a6
>                               5. h4 a5 6. a4H Kd6H 7. Kh3H Kc6H 8. f5H Kd6H
>                               9. f6H Kd7H 10. h5H Ke6H {HT} {80}
> 692694548 12:30.6   2.26 20t  1. Rd7+ Rxd7 2. cxd7 Kxd7 3. Kg2 Ke7 4. Kf3 a6
>                               5. h4 a5 6. a4 Kf7 7. Ke4 Ke6 8. f4 Kd6 9. f5
>                               gxf5+ 10. Kxf5 Ke7 {HT} {80}
> 724061159 13:05.8   2.26 20.  1. Rd7+ Rxd7 2. cxd7 Kxd7 3. Kg2 Ke7 4. Kf3 a6
>                               5. h4 a5 6. a4 Kf7 7. Ke4 Ke6 8. f4 Kd6 9. f5
>                               gxf5+ 10. Kxf5 Ke7 11. Ke4H Kf7H 12. Kf4H Ke7H
>                               {HT} {80}
> 772805567 14:01.9   2.38 21t  1. Rd7+ Rxd7 2. cxd7 Kxd7 3. Kg2 Ke7 4. Kf3 a6
>                               5. h4 a5 6. a4 Kd6 7. Ke4 Ke6 8. f4H Kd6H 9.
>                               f5H gxf5+H 10. Kxf5H Kc6H {80}
> 878453817 15:59.7   2.38 21.  1. Rd7+ Rxd7 2. cxd7 Kxd7 3. Kg2 Ke7 4. Kf3 a6
>                               5. h4 a5 6. a4 Kd6 7. Ke4 Ke6 8. f4 Kd6 9. f5
>                               gxf5+ 10. Kxf5 Kc6 {80}
> 949272646 17:18.8   2.61 22t  1. Rd7+ Rxd7 2. cxd7 Kd8 3. Kg2 Kxd7 4. f4H
>                               Ke7H 5. Kg3H Kd6H 6. Kf3H Ke7H 7. Ke3H Kd7H 8.
>                               f5H gxf5H 9. Kf4H Ke6H 10. h4H a6H 11. a3H Ke7H
>                               12. Kxf5H h6H {HT} {80}
> 989481947 18:02.7   2.61 22.  1. Rd7+ Rxd7 2. cxd7 Kd8 3. Kg2 Kxd7 4. f4 Ke7
>                               5. Kg3 Kd6 6. Kf3 Ke7 7. Ke3 Kd7 8. f5 gxf5 9.
>                               Kf4 Ke6 10. h4 a6 11. a3 Ke7 12. Kxf5 h6 {HT}
>                               {80}
>
>Your point reminds me of a postion Steffen Jakob showed here once:
>
>[D] 6k1/2pq4/5Q2/p2PPP2/1p1P4/8/P6P/7K w - - am Qe6;
>
>Here the trade to the pawn endgame loses.
>
>Regards,
>Dieter



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.