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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

Thank you!!

Richard

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

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.

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.

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.

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!!

Ideas for future test suites are outlined here:
http://sites.google.com/site/strategict ... al-ideas-1

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

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)

Critter 0.41 (development version):

10 sec / position on Athlon64 4200+

73 of 100 matching