Update to 'Chess Endgame Records'

Endgame analysis using tablebases, EGTB generation, exchange, sharing, discussions, etc..
Post Reply
Posts: 489
Joined: Sat Jan 21, 2006 10:43 am
Sign-up code: 10159
Location: Reading, UK

Update to 'Chess Endgame Records'

Post by guyhaw »

I have updated the 'Chess Endgame Records' dataset/pgn to 'version 7' at http://centaur.reading.ac.uk/34268/

The most significant additions are:

1) A timeline for the history of Endgame Table generation and publication (comments, corrections, additions welcome),

2) Ply-count-critical examples of maxDTM50 positions and DTM50-minimaxing lines from Galen Huntington:
KQKRB, KQKRP, KBNKN, KNNKP, KPPKP, KQPKQ and KBBKNN (covering maxDTM50 w-b_P-less/P-ful positions and others)

3) Examples of maxDTZ50' position and DTZ50'-minimaxing lines from Ronald de Man's 'syzygy' EGTs:
KQKBBN, KQKBBP, KQKBNP, KBBKNN, KQPKRB and KRRPKQ (covering maxDTZ50' w-b_P-less/P-ful positions and others substantiating these).
The KRRPKQ position is a maxDTC sub-7-man (beating the well known KRNKNN position by one ply), and maxDTM/DTZ50' s7m_P-ful.
It may also be maxDTZ s7m_P-ful but it's not possible to say yet.

ICGA_J 37-1 'Chess Endgame News', also at http://centaur.reading.ac.uk/37158/ with supporting pgn, gives some commentary on the latest EGT contributions from Galen and Ronald de Man.

The completeness and clarity of the information coming through the FRITZ14 GUI interface depends on the quality of the sw-integration of the GUI and the syzygy EGTs. Chessbase have fixed the bug whereby move-depth only clocked down '1' per 4 plies (for DTZ50' > 100p) in Chessbase12 but not yet in FRITZ14. I have no experience of the behaviour of the HOUDINI4 and STOCKFISH interfaces to these EGTs.

I am looking for examples of positions with dtz50' > dtz, dtz50' > 100 ply ... and dtz variously less than 10p, 100p or 1000p (of which the KRRPKQ position is one). These may not be discovered until 6m P-ful DTZ EGTs are available.

Also, there is an example in 'CER' of a position with dtz = 1p and dtz50' = 99p, there is no example of a (possible) position with dtz = 1p, dtz50' = 100p. Maybe there is one in KNNKNP or KNNKPP.

Post Reply