Reply
 
LinkBack Thread Tools Display Modes
  #1   Report Post  
Old June 7th 10, 05:30 PM posted to rec.games.chess.misc,rec.games.chess.analysis
external usenet poster
 
First recorded activity by ChessBanter: Mar 2009
Posts: 3,536
Default My computer fails to find the solution to this Babson task--canyours?

1q5R/P2N4/5p2/2p2p2/2Pk1b1n/6P1/PNpP1P1K/BQ3R1B w - - 0 1

The Babson Task (Leonid Yarosh, 1983)

This position is from a problem--white to mate in four--that even my
PC has not found with fifteen minutes of time running (Fritz 5.3 on a
Pentium IV). It only finds mate in five, which is incorrect. One
chess master, a Frenchman P. Drumare, spent four hours a day for over
four years and could not solve it by hand.

Can you or yours?

RL

http://en.wikipedia.org/wiki/Babson_task

The Babson task is a kind of chess problem of the form "white to move
and mate black in N moves against any defence" with the following
play:
White makes his first move.
Black defends by promoting a pawn to queen, rook, bishop or knight.
White responds by promoting a pawn to queen, rook, bishop or knight
respectively (if black promoted to rook, so does white, if black
promoted to knight, so does white and so on). No other promotion (or
any other move) leads to mate in the stipulated number of moves.

The task is named after the first person to speculate about the
possibility of such a problem, Joseph Ney Babson. It is regarded as
one of the greatest challenges for a composer of chess problems to
devise a satisfying Babson task problem, and for around half a century
the task was considered to be near-impossible in directmate form.

Technically, the task can be regarded as a form of Allumwandlung with
corresponding promotions by black and white (an Allumwandlung is a
problem which contains, at some point in the solution, promotions to
each of the four possible pieces such problems had already been
composed before Babson devised his task).
  #2   Report Post  
Old June 7th 10, 06:22 PM posted to rec.games.chess.misc,rec.games.chess.analysis
external usenet poster
 
First recorded activity by ChessBanter: Jun 2009
Posts: 3,256
Default My computer fails to find the solution to this Babson task--canyours?

On Jun 7, 12:30*pm, raylopez99 wrote:
1q5R/P2N4/5p2/2p2p2/2Pk1b1n/6P1/PNpP1P1K/BQ3R1B w - - 0 1

The Babson Task (Leonid Yarosh, 1983)

This position is from a problem--white to mate in four--that even my
PC has not found with fifteen minutes of time running (Fritz 5.3 on a
Pentium IV). *It only finds mate in five, which is incorrect. *One
chess master, a Frenchman P. Drumare, spent four hours a day for over
four years and could not solve it by hand.

Can you or yours?

RL

http://en.wikipedia.org/wiki/Babson_task


The solution, 1.Rxh4, appears to be correct, and does yield a mate
in four. However, Rybka doesn't see it as mate in /four/ until after
1.Rxh4 is played. It shows an evaluation of + #5, then a few seconds
after 1.Rxh4 it switches to #4. With Fritz8, it sees 1.Rxh4 as a mate
in six, then after it's played a mate in four, except in the line
1...cxb1B, where it still thinks an extra move is required until
2.axb8B is actually played.
This is not unusual with engines and complex problems, in my
experience. The engine sees a mate, but not in the required number of
moves, and then when the key is played it suddenly does come up with
the right number of moves. I don't know why it happens, but it often
does. Perhaps Dr. Dowd knows why?
  #3   Report Post  
Old June 7th 10, 08:19 PM posted to rec.games.chess.misc,rec.games.chess.analysis
external usenet poster
 
First recorded activity by ChessBanter: Mar 2009
Posts: 3,536
Default My computer fails to find the solution to this Babson task--canyours?

On Jun 7, 8:22*pm, Taylor Kingston
wrote:

* The solution, 1.Rxh4, appears to be correct, and does yield a mate
in four. However, Rybka doesn't see it as mate in /four/ until after
1.Rxh4 is played.


How did you know the solution was 1.Rxh4? This is well known problem,
is that it?


It shows an evaluation of + #5, then a few seconds
after 1.Rxh4 it switches to #4. With Fritz8, it sees 1.Rxh4 as a mate
in six, then after it's played a mate in four, except in the line
1...cxb1B, where it still thinks an extra move is required until
2.axb8B is actually played.


Right. Fritz 5.3 did the same thing--after I input the winning move
it saw everything.

* This is not unusual with engines and complex problems, in my
experience. The engine sees a mate, but not in the required number of
moves, and then when the key is played it suddenly does come up with
the right number of moves. I don't know why it happens, but it often
does. Perhaps Dr. Dowd knows why?


Who is Dr. Dowd?

I just played your two games that you beat the experts in Ohio
on...the second one was classic...what a blunderfest! Will reply in
the other thread.

RL

  #4   Report Post  
Old June 7th 10, 09:01 PM posted to rec.games.chess.misc,rec.games.chess.analysis
external usenet poster
 
First recorded activity by ChessBanter: Apr 2007
Posts: 3,170
Default My computer fails to find the solution to this Babson task--canyours?

On 7 June, 17:30, raylopez99 wrote:
1q5R/P2N4/5p2/2p2p2/2Pk1b1n/6P1/PNpP1P1K/BQ3R1B w - - 0 1
One
chess master, a Frenchman P. Drumare, spent four hours a day for over
four years and could not solve it by hand.


Four hours a day for four years!
Wow. That is roughly 300 times 4, that's 1200, plus, er, 65 times 4.
That's the same as 130 times 2. So 160, um... er.... 1330 times 4 is,
um...
I think I need a computer.
About 5000 hours solving a single puzzle "by hand" - whatever that
means - is a lot of time.
  #5   Report Post  
Old June 7th 10, 09:04 PM posted to rec.games.chess.misc,rec.games.chess.analysis
external usenet poster
 
First recorded activity by ChessBanter: Apr 2007
Posts: 3,170
Default My computer fails to find the solution to this Babson task--canyours?

On 7 June, 20:19, raylopez99 wrote:

Who is Dr. Dowd?


Boy George.


  #6   Report Post  
Old June 7th 10, 09:39 PM posted to rec.games.chess.misc,rec.games.chess.analysis
external usenet poster
 
First recorded activity by ChessBanter: Sep 2007
Posts: 163
Default My computer fails to find the solution to this Babson task--canyours?

On 7 June, 21:01, Offramp wrote:
On 7 June, 17:30, raylopez99 wrote:

1q5R/P2N4/5p2/2p2p2/2Pk1b1n/6P1/PNpP1P1K/BQ3R1B w - - 0 1
One
chess master, a Frenchman P. Drumare, spent four hours a day for over
four years and could not solve it by hand.


Four hours a day for four years!
Wow. That is roughly 300 times 4, that's 1200, plus, er, 65 times 4.
That's the same as 130 times 2. So 160, um... er.... 1330 times 4 is,
um...
I think I need a computer.
About 5000 hours solving a single puzzle "by hand" - whatever that
means - is a lot of time.


What Drumare actually (apparently) spent four hours a day doing was
trying to *compose" a Babson task - see http://www.chessbase.com/puzzle/puzz13a.htm,
for instance.
  #7   Report Post  
Old June 7th 10, 10:08 PM posted to rec.games.chess.misc,rec.games.chess.analysis
external usenet poster
 
First recorded activity by ChessBanter: Jul 2006
Posts: 1,015
Default My computer fails to find the solution to this Babson task--canyours?

On 07/06/2010 18:22, Taylor Kingston wrote:
1q5R/P2N4/5p2/2p2p2/2Pk1b1n/6P1/PNpP1P1K/BQ3R1B w - - 0 1


Shredder10 gets it in 17s at ply 18
Stockfish 1.51 gets it in 5s at ply 9

Regards,
Martin Brown
  #8   Report Post  
Old June 7th 10, 10:45 PM posted to rec.games.chess.misc,rec.games.chess.analysis
external usenet poster
 
First recorded activity by ChessBanter: Jun 2009
Posts: 3,256
Default My computer fails to find the solution to this Babson task--canyours?

On Jun 7, 5:08*pm, Martin Brown
wrote:
On 07/06/2010 18:22, Taylor Kingston wrote:

1q5R/P2N4/5p2/2p2p2/2Pk1b1n/6P1/PNpP1P1K/BQ3R1B w - - 0 1


Shredder10 gets it in 17s at ply 18
Stockfish 1.51 gets it in 5s at ply 9

Regards,
Martin Brown


Well then, those two engines are definitely better at this sort of
thing than Fritz 8 and Rybka 3.1.
  #9   Report Post  
Old June 7th 10, 11:02 PM posted to rec.games.chess.misc,rec.games.chess.analysis
external usenet poster
 
First recorded activity by ChessBanter: Jun 2009
Posts: 3,256
Default My computer fails to find the solution to this Babson task--canyours?

On Jun 7, 3:19*pm, raylopez99 wrote:
On Jun 7, 8:22*pm, Taylor Kingston
wrote:


* This is not unusual with engines and complex problems, in my
experience. The engine sees a mate, but not in the required number of
moves, and then when the key is played it suddenly does come up with
the right number of moves. I don't know why it happens, but it often
does. Perhaps Dr. Dowd knows why?


Who is Dr. Dowd?


Stephen Dowd. He posts here under the name "sd". He is an expert on
the subject of chess problems, an area of the game I know little about.
  #10   Report Post  
Old June 8th 10, 12:24 AM posted to rec.games.chess.misc,rec.games.chess.analysis
external usenet poster
 
First recorded activity by ChessBanter: Oct 2007
Posts: 3,073
Default My computer fails to find the solution to this Babson task--canyours?

On Jun 7, 4:04*pm, Offramp wrote:
On 7 June, 20:19, raylopez99 wrote:

Who is Dr. Dowd?


Boy George.


HAAA!!!
Reply
Thread Tools
Display Modes

Posting Rules

Smilies are On
[IMG] code is Off
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On


Similar Threads
Thread Thread Starter Forum Replies Last Post
The Mystery of the USCF Computer Taken by Miss P samsloan rec.games.chess.politics (Chess Politics) 78 March 2nd 08 04:32 AM
The Mystery of the USCF Computer Taken by Miss P samsloan rec.games.chess.misc (Chess General) 67 March 2nd 08 04:32 AM
The Mystery of the USCF Computer Taken by Miss P samsloan alt.chess (Alternative Chess Group) 46 March 2nd 08 04:32 AM
Response to Ethics Complaint by Herbert Rodney Vaughn samsloan rec.games.chess.politics (Chess Politics) 15 January 15th 07 07:17 AM
Response to Ethics Complaint by Herbert Rodney Vaughn samsloan rec.games.chess.computer (Computer Chess) 2 January 14th 07 01:41 AM


All times are GMT +1. The time now is 11:57 PM.

Powered by vBulletin® Copyright ©2000 - 2019, Jelsoft Enterprises Ltd.
Copyright 2004-2019 ChessBanter.
The comments are property of their posters.
 

About Us

"It's about Chess"

 

Copyright © 2017