CCRL Discussion Board

Next step: 7men bitbases!? Their sizes should be comparable with a the size of the 6men tablebases.
But who will generate them?

Here is a new example - a position from the 2nd game of the Topalov-Kramnik WCh match: 6k1/1p2r3/3K4/6N1/3P4/8/8/8 b - - 0 1 1...Re1? [1...Re3! was the only winning move 2.d5 Kf8 3.Kd7 b5 4.Ne6+ Kg8! Switchback 5.d6 b4 6.Ke7 b3 7.d7 Rd3 8.Nc5 Rxd7+! 9.Kxd7 b2-+] 2.d5 Kf8 3.Ne6+? [Only the natural 3....

Sorry Andrey, I don't have the EG165. :( I have realised that Guy's file contains only the main line and I am convinced that your study contains many interesting sidelines. I didn't analysed very hard the positions after the reciprocal zugzwang(the anticipated part of the new study). It is very inte...

Andrey, what do you think of this study? (see the pgn file!)
Can it be a joined composition?

Sorry Guy, I still think it works. Don't you think that every position has a maximal length Unique Move Sequence? That length gives us the DTE for a position. Wilhelm gives exactly that number. Or put it this way: The black can choose between moves: -a black move which leads to a position with more ...

A database with new metrics - DTE - Depth To End (of the study) - can be created. All positions with duals have DTE=0 (there the study ends). A mate position has DTE 0, a position with uniqe mating move has DTE 1 etc. In a stalemate position we have DTE=0 (this could be the end of a stalemate study)...

It seems that the incomplete tablebases are good only for analysing with an engine. The engine can complete the list with evaluation of the moves analysing itself the missing positions which occur after transformation. But when is playing a game, the GUI may choose another move even when the engine ...

Today the incomplete database problem never occur. You can get perfect results with the KPPKPP even with no 5men databases installed. The engine tries to calculate if a position from a missing database is reached, but every KPPKPP position is correctly evaluated. So even having only some of the 6men...

Nice results, Marc!

What's your plans about releasing some of the databases? Can you tell us the size of them? Or it would be more simple to construct 7men bitbases and to release them!?
And for me it would be nice to have the mutual zugzwang lists - I'm a study composer.

Arpi

What would be the size of the 7men bitbases?

I have attached a small collection of endgame studies with 6men tablebase positions. The database has an endgame key with all material configurations up to 6 pieces (you can select it by the "Endgames" tab in Chessbase). This endgame key can be imported to every .cbh database and you insta...

Marc, let's see if you can reproduce Eugene's .tbs for KPPKPP: wtm: Lost in 0: 16424 wtm: Lost in 1: 507796 wtm: Lost in 2: 496720 wtm: Lost in 3: 1147055 wtm: Lost in 4: 3032634 wtm: Lost in 5: 10848451 wtm: Lost in 6: 18353722 wtm: Lost in 7: 23912416 wtm: Lost in 8: 28010956 wtm: Lost in 9: 34162...

Another major interest of tablebases is to analyse many studies ( and cook some) . Study composers , problem composers too probably , may use them. Yes, at least half of the QN/Q studies from your database are cooked. :( As a study composer I often use the tablebases: 1.indirectly - analysing with ...

I think most of the chessplayers don't have the 3-5men tablebases either, so the problem is not only the big storage size. They don't know what are the endgame tablebases or how to get them.

At the http://www.chessbase.com site on 13.05.2006 the "star Grandmaster annotator" Mihail Marin is analysing some games from the MTel tournament. In one of the games (Kamsky-Bacrot), a Rook endgame is reached, which eventualy becames a KRP/KRP tablebase position. During the analyse anothe...

ed2k://|file|tbgen.zip|111087|792A1D54FD96940D3937915F5F0BC320|h=253EQJBGABX4FANURRNM44D5QYEE5NT2|/

I think I have the source code of the version of tbgen to create 6 men tablebases! I downloaded from Crafty's site two years ago. I have put it on emule (tbgen.zip).

Can a WDL base, like the new Shredderbase, use the 50 moves rule?
If I understand corectily, Shredder 10 UCI uses for playing the Nalimov databases and only for analysis the Shredderbase, exactly for that reason.