Bishop Verses Knight EPD test suite

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Dann Corbit
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Location: Redmond, WA USA

Bishop Verses Knight EPD test suite

Post by Dann Corbit »

Material imbalance is certainly one of important new ideas in chess programming.

Sometimes a knight is better and sometimes a bishop, though they have approximately the same point value in general.

When should you trade a knight for a bishop (and vice versa)?
What about the aftermath of the trade (e.g. with a pawn recapture, has the altered pawn structure changed the value of the trade)?

There is a new test suite in the "Strategic Test Suite" arsenal, the fifth of the series by Swaminathan. These positions have had the stuffings pounded out of them by powerful chess engines to ensure that the answers provided are reliable. Besides the key move, there is also a list of hints in the ce that shows the relative value of alternate move choices.

Want to give it a whirl? Take a look here, and help yourself! :
http://sites.google.com/site/strategict ... -vs-knight
Richard Allbert
Posts: 792
Joined: Wed Jul 19, 2006 9:58 am

Re: Bishop Verses Knight EPD test suite

Post by Richard Allbert »

Thank you!!

Richard :D
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michiguel
Posts: 6401
Joined: Thu Mar 09, 2006 8:30 pm
Location: Chicago, Illinois, USA

Re: Bishop Verses Knight EPD test suite

Post by michiguel »

Dann Corbit wrote:Material imbalance is certainly one of important new ideas in chess programming.

Sometimes a knight is better and sometimes a bishop, though they have approximately the same point value in general.

When should you trade a knight for a bishop (and vice versa)?
What about the aftermath of the trade (e.g. with a pawn recapture, has the altered pawn structure changed the value of the trade)?

There is a new test suite in the "Strategic Test Suite" arsenal, the fifth of the series by Swaminathan. These positions have had the stuffings pounded out of them by powerful chess engines to ensure that the answers provided are reliable. Besides the key move, there is also a list of hints in the ce that shows the relative value of alternate move choices.

Want to give it a whirl? Take a look here, and help yourself! :
http://sites.google.com/site/strategict ... -vs-knight
Gaviota, "Flock version" 0.68.1
AMD 2x 2.4 Ghz (2 cores used), 16MB hash tables.

10 seconds/test

average nps: 572564
solved: 65
wrong : 35
ratio : 65.00%

Miguel
vladstamate
Posts: 161
Joined: Thu Jan 08, 2009 9:06 pm
Location: San Francisco, USA

Re: Bishop Verses Knight EPD test suite

Post by vladstamate »

Plisk 0.1.2 Phenom running on AMD Phenom 2.6Ghz (using 1 core only and 128Mb hash):

10 sec/move - 67/100 (67%)

gen> nNodes: 729653264 nQSNodes: 160044559 branchFactor: 3.64 avgDepth: 10.7

Regards,
Vlad.
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opraus
Posts: 166
Joined: Wed Mar 08, 2006 9:49 pm
Location: S. New Jersey, USA

Re: Bishop Verses Knight EPD test suite

Post by opraus »

Thanks to you guys for these tests!

10 sec / pos ; 1 core of core 2 duo 2 Ghz ; 375 Knps

Xpdnt gets 79/100 [this includes the 'alternate' moves]

It seemed to me, [just by 'eye'] that it favored the Bishop more than the knight. ... gives me reason to experiment with that a bit.

Thanks again.
swami
Posts: 6640
Joined: Thu Mar 09, 2006 4:21 am

Re: Bishop Verses Knight EPD test suite

Post by swami »

Thanks to you all for reporting the results from your engines! Keep 'em coming!!

It should be noted though that Dann put several hundreds of analysis into tests with top engines and he did a careful selection which is impressive. He is an expert when it comes to test suite selections, owing to his years of experience. Great to work with him.
swami
Posts: 6640
Joined: Thu Mar 09, 2006 4:21 am

Re: Bishop Verses Knight EPD test suite

Post by swami »

By the way, If any of you would like to send a short 1-2 line testimonials/feedback, I'd be sure to put them with your name and the name of your engine, in the site here:

http://sites.google.com/site/strategict ... stimonials

So feel free to send words to me via pm or here.

We will keep working on it together, Have plans to release 20 more test suites in the series!! :D

Ideas for future test suites are outlined here:
http://sites.google.com/site/strategict ... al-ideas-1
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michiguel
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Joined: Thu Mar 09, 2006 8:30 pm
Location: Chicago, Illinois, USA

Re: Bishop Verses Knight EPD test suite

Post by michiguel »

michiguel wrote:
Dann Corbit wrote:Material imbalance is certainly one of important new ideas in chess programming.

Sometimes a knight is better and sometimes a bishop, though they have approximately the same point value in general.

When should you trade a knight for a bishop (and vice versa)?
What about the aftermath of the trade (e.g. with a pawn recapture, has the altered pawn structure changed the value of the trade)?

There is a new test suite in the "Strategic Test Suite" arsenal, the fifth of the series by Swaminathan. These positions have had the stuffings pounded out of them by powerful chess engines to ensure that the answers provided are reliable. Besides the key move, there is also a list of hints in the ce that shows the relative value of alternate move choices.

Want to give it a whirl? Take a look here, and help yourself! :
http://sites.google.com/site/strategict ... -vs-knight
Gaviota, "Flock version" 0.68.1
AMD 2x 2.4 Ghz (2 cores used), 16MB hash tables.

10 seconds/test

average nps: 572564
solved: 65
wrong : 35
ratio : 65.00%

Miguel
1 minute/ position

average nps: 602136
solved: 74
wrong : 26
ratio : 74.00%

Miguel
yanquis1972
Posts: 1766
Joined: Wed Jun 03, 2009 12:14 am

Re: Bishop Verses Knight EPD test suite

Post by yanquis1972 »

those seem like fantastic results for an amateur engine!

i dont know that a bias towards retaining the bishop pair is a bad thing. (though i realize thats not necessarily what you say the case is)
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rvida
Posts: 481
Joined: Thu Apr 16, 2009 12:00 pm
Location: Slovakia, EU

Re: Bishop Verses Knight EPD test suite

Post by rvida »

Critter 0.41 (development version):

10 sec / position on Athlon64 4200+

73 of 100 matching