Endgame study rules of composition

[Alan Tomalty]

I have tried to find the rules on the internet but to no avail. I am specifically asking whether it is the responsibility of the composer to prove that all the variations fail. Obviously there are certain positions where the tree of variations is almost infinite but in general isn't it the responsibility of the composer to prove that his study is sound? If it is up to the solver, then there could be many positions where it is impossible to prove that the study is cooked or busted. I would think that that is the responsibility of the composer. To that end numbers 73 and 74 in Nunn's Endgame Challenge are possible busts but the variation tree seems too large to prove one way or the other. Houdini has found alternatives to Nunn's analysis but proving a bust would take years. Readers will note that no.s 21 and 31 are completely busted. 21 is busted by the 6 man tablebase and the bust on 31 was published on the internet years ago as previously noted in another post on Chess Chat.

[Alan Baljeu]

Re: Endgame study rules of composition

It is the composer's responsibility to prove the study correct, but not to publish all variations. Publish the correct line of play and the most interesting tries.

[Normand Arsenault]

Re: Endgame study rules of composition

I have tried to find the rules on the internet but to no avail. I am specifically asking whether it is the responsibility of the composer to prove that all the variations fail. Obviously there are certain positions where the tree of variations is almost infinite but in general isn't it the responsibility of the composer to prove that his study is sound? If it is up to the solver, then there could be many positions where it is impossible to prove that the study is cooked or busted. I would think that that is the responsibility of the composer. To that end numbers 73 and 74 in Nunn's Endgame Challenge are possible busts but the variation tree seems too large to prove one way or the other. Houdini has found alternatives to Nunn's analysis but proving a bust would take years. Readers will note that no.s 21 and 31 are completely busted. 21 is busted by the 6 man tablebase and the bust on 31 was published on the internet years ago as previously noted in another post on Chess Chat.

Great question Al. I was wondering the same.

Norm

[Alan Tomalty]

Re: Endgame study rules of composition

It is the composer's responsibility to prove the study correct, but not to publish all variations. Publish the correct line of play and the most interesting tries.

How does the composer prove that his study is sound without publishing all the variations? If he keeps some to himself then he hasn't proved anything to the public. If the variation tree is too large (and I would accept any position value more than 2 points plus as acceptable proof by Houdini) then it would be impossible to prove that the study is sound. In that case I would deem the study as not finished. To that end No. 73 and 74 have not been proved sound as far as I am concerned. Specifically in No.73 Nunn gives 1.Kd5 Nd2
2.Kd4 Bb1 3.Na6 Kf7 but Houdini3 gives 3....Bg6 intending 4.....Be8 and I see Houdini's idea of a defence for Black. In No.74 Nunn gives 1.Nf6 Kf7
2.Nxg4 Ne6 3.Kf5 Be1 4.Ne5 Ke7 5. Nc6 Kd7 6.c4 Nc5 7.Ne5 Kc8 but Houdini gives 7.....Kc7. Even in Nunn's line after 8.Nf3 Houdini gives 8....Bc3 instead of Nunn's 8....Ba5.
NO. 73


NO. 74

[Alan Baljeu]

Re: Endgame study rules of composition

In my opinion, prove it by whatever means you choose. The recipients of the study don't want reams upon reams of data. They will review your answer, and then evaluate it themselves. If they find a fault in it - and they will also use a computer to analyse to be sure - then it is faulty and you didn't do your job.

Nunn is experienced in endgame studies, composition, etc. That he also failed to give complete correct answers only means that apparently the standard of proof isn't always met by even the upper tier. Which means for you, just do your best.

[Egidijus Zeromskis]

Re: Endgame study rules of composition

Nunn's Endgame Challenge

I would suggest that you contact Nunn directly and discuss your findings. Maybe he has already revised his book with new engines and tablebases. The book was published 10 years ago, probably one or two years took to prepare it.