CCRL Discussion Board

John Tamplin computed 6-man pawnless EGTs using Marc Bourzutschky's program GTBGEN, a generalised version of Nalimov's TBGEN, in which I believe MB also had a hand. John and I published results about the DTC EGTs and the 'Nalimov-style' stats files are certainly available. I suspect that some of the...

g

A colleague is experiencing difficulties with FRITZ taking a very long time, and oftern 'timing out', when contemplating the fact that it has all the sub-7-man Nalimov EGTs to work with. I have suggested only making available those EGTs that are likely to be relevant but the real question is: What a...

I am not sure I understand the last question (as there are several 'databases' in play), but here's an attempted answer: 1) CQL can subset into a .pgn file all those studies in HvdH's dbIII database where (a) the result is marked as 1-0 and (b) the mainline includes a sub-7-man position. [... or the...

Have also discovered 3,356 cases of White making a non-DTM-optimal move, which indicates some sort of dual.

These occur in 2,485 studies: about 1/3rd of these have an '@' in the Event tag, indicating that some sort of flaw is already known about them - maybe the dual I've picked up, maybe not.

g

My results are available in pairs of spreadsheets - one set for 'Draw Studies' and the other set for 'Win Studies'. However, they can only be followed up in context if you have the HvdH dbIII of Studies. The smallest pair of spreadsheets just gives the first position and the first 'failure indicator...

Eiko Bleicher and I have mined the remarkable Chess Study Database III, compiled by Harold van der Heijden and aailable via all good chess shops and via http://home.studieaccess.nl/heijd336/home.html. At this version, it includes 67,691 studies. Using CQL ( http://rbnn.com/cql/contents.html ), pgn2f...

There's always another statistic to go for! For example, sub-7-man statistics will not be complete until positions with castling rights are included. As for the DTC EGTs, I imagine Marc B has DTC(onversion) statistics ... number of positions of DTC depth 'n' measured in winner's moves. They could ea...

A good offer by Shaun and one I hope he does not regret.

'Nalimov' EGTs do not cover 5-1 chess or positions with castling rights.

Marc B has computed 5-1 EGTs to the DTC(onversion) metric: I have the zugs but not the stats.

g

Yes, I did.

I've obviously been surviving on a forward reference for some time.

Thanks KK - Guy

g

... the 58 (6-man 5-1p K(Q/R/B)NPPK zugs in a Knight's tour: e.g. 5NKQ/4k1PP/8/8/8/8/8/8 w … (a wtm draw but a btm win) ... the bK shuttles e7/e8 to keep the White force (including a Q, R or B) pinned in the corner and the wN is always on the wrong foot: (wN on f8) – Ng6 – Nh4 – Ng2 – Ne1 – Nc2 – Na...

Interesting - are you saying that the 2nd version of the 'mate in 545m' makes apparent sense when viewed in DTC terms? I'd certainly expect the DTC-minimaxing and DTM-minimaxing lines to go along in coincidence for quite a long time. Good to have more expertise on the block if that's the case. We're...

Joe Hurd and I contributed a paper on 'Data Assurance in Opaque Computations' to the ICGA ACG12 Conference this year in Pamplona. Proceedings are not yet out. It was a second follow-up to Joe's paper on HOL and EGTs: our first follow-up was too long to limbo under the conference ration of 12pp :-( W...

There's a lot of rubbish in the rybkaforum thread cited - but the idea of videoing an endgame and overlaying a sound track to communicate extra inforamtion is interesting. Marc's EGT is to DTC so the fact is that 'Depth to Conversion' = 517 moves (given that the two sides are respectively minimising...

Rafael stopped maintaining WILHELM some time ago. There's no reason to assume it works with VIsta. If you are getting 'FAIL' messages with WILHELM, it could be that you are not describing your files as DTM files. WILHELM, or at least the version I had, could check EGTs to the DTC and DTZ metrics as ...

Les, I should have said on Wednesday, and meant to say, that Marc B obviously found the 5-1p zugs and their 'DTC' Depths to Conversion by trawlling EGTs generated by Yakov Konoval's program. FEG generates EGTs to the DTMate metric, so those could not have been the ones used. I don't know what form o...

Marc B has kindly advised me that there are no zugs in pawnless 5-1 chess but that there are 293 in 5-1p chess. These appear in the endgames K(B/Q/R)NPPK and K(B/N/P/R)PPPK and are listed by endgame below, and are of course all 'Type 2' 'draw-win' zugs. There are some 'sets of 58' zugs with the Knig...

The URL you are looking for is, I think, not 'icg.org' but 'www.icga.org' ... and thence by 'Game-Specific Info' to 'Western Chess' and 'Chess Endgames'.

g

Longtime readers here may remember that a faulty KBPKN stats file 'got into the system', emanating I think from Rob Hyatt's site which was the original promulgation point for Nalimov's EGTs. I've sometimes wondered what the erronous file was actually the stats of - it looked like a 5-man EGT but I n...

I sympathise with your point of view hgm. Anyway, MB reports that there are no zugs in 5-1 Pawnless chess. g

Before we used MD5sum file-signatures, was there any checking of Nalimov EGTs?

Did datacomp do something: were there block-level checksums guarding the compression/decompression?

I ought to know this, and if I ever knew, I've forgotten.

g

A strong zugzwang (which is what I really meant) is where the theoretical value goes up 0.5 or 1.0 points if one does not have the move.

Where the number of moves goes down but the value stays the same, one has a 'weak zugzwang'.

g

Please note that I edited the FEN for the sole full-point (Type 3) zug in KBBNNKQ: It should have been ... 8/8/8/8/4q3/2k4N/5B2/N1K2B2: wtm, 0-1 in DTZ/M = 12; btm, 1-0 in DTZ/M = 42. Marc Bourzutschky remarks that this is notable for being pawnless AND only having two Ns: see EG Vol 11-162 (2006) p...

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