Lazy_Frank wrote: ↑Thu Jun 16, 2022 2:54 pm
For me interesting is question: how long is longest forced win DTM for n-TB.
Someone may suggest: if 8-TB longest mate took 584 moves, then 9-TB can be ~ 584*2=1168 moves, 10-TB ~ 584*4=2336 moves and so on.
But i don't think so it works like than.
Why?
My suggestion is actually simple:
Side with advantage tend to get maximum mobility before conversion (capture or mate).
FEN "R7/8/8/8/7q/2K1B2p/7P/2Bk4 w - - 0 1"
Zeroing at move 584w.
Mate at move 592w.
White maximum mobility: 40 moves at move 256, 39 moves at move 489.
Black maximum mobility: 32 moves at move 103, 31 moves at move 177.
In other words: mate distance for side with advantage depends of how fast (or slow) can get maximum pieces mobility.
I don't think any forced win (DTM for any TB) ever exceeds 1000 moves.
Even 594 is a very big number.
But i need a patience ... to get answer.
I guess that there is a forced mate with more than 1000 moves but
I think it may be better to see what happens in smaller boards than 8*8 first.
Do people know what is the maximal distance to mate in 3*3 board,3*4 boards,4*3 boards and 4*4 boards as a function of number of pieces?
Lazy_Frank wrote: ↑Thu Jun 16, 2022 2:54 pm
For me interesting is question: how long is longest forced win DTM for n-TB.
Someone may suggest: if 8-TB longest mate took 584 moves, then 9-TB can be ~ 584*2=1168 moves, 10-TB ~ 584*4=2336 moves and so on.
But i don't think so it works like than.
Why?
My suggestion is actually simple:
Side with advantage tend to get maximum mobility before conversion (capture or mate).
FEN "R7/8/8/8/7q/2K1B2p/7P/2Bk4 w - - 0 1"
Zeroing at move 584w.
Mate at move 592w.
White maximum mobility: 40 moves at move 256, 39 moves at move 489.
Black maximum mobility: 32 moves at move 103, 31 moves at move 177.
In other words: mate distance for side with advantage depends of how fast (or slow) can get maximum pieces mobility.
I don't think any forced win (DTM for any TB) ever exceeds 1000 moves.
Even 594 is a very big number.
But i need a patience ... to get answer.
I guess that there is a forced mate with more than 1000 moves but
I think it may be better to see what happens in smaller boards than 8*8 first.
Do people know what is the maximal distance to mate in 3*3 board,3*4 boards,4*3 boards and 4*4 boards as a function of number of pieces?
My personal Opinion about the 8-piece endgame tablebases is that it will make weaker engines that are about 200 Elo weaker than Stockfish and Komodo Dragon to get more draws, and this will NOT reflect the true strength of the weaker engine in question because
every time that the position reach 8-pieces endgame the weaker engine will get the benefit of drawing instead of letting the two engines that are competing show why the are superior to the other engine. What will be the purpose of testing engines? To the stop them once engine X reach a superior position over engine Y during the middlegame ?
Note: I hope that in tournaments they can allow two human players to use endgame book showing all the endgame positions up to 8-pieces and to play it against your stronger opponent. Example a 2200 Fide player playing versus a 2600 or 2700 will not have any problem drawing most games once they reach 8- pieces
Lazy_Frank wrote: ↑Thu Jun 16, 2022 2:54 pm
For me interesting is question: how long is longest forced win DTM for n-TB.
Someone may suggest: if 8-TB longest mate took 584 moves, then 9-TB can be ~ 584*2=1168 moves, 10-TB ~ 584*4=2336 moves and so on.
But i don't think so it works like than.
Why?
My suggestion is actually simple:
Side with advantage tend to get maximum mobility before conversion (capture or mate).
FEN "R7/8/8/8/7q/2K1B2p/7P/2Bk4 w - - 0 1"
Zeroing at move 584w.
Mate at move 592w.
White maximum mobility: 40 moves at move 256, 39 moves at move 489.
Black maximum mobility: 32 moves at move 103, 31 moves at move 177.
In other words: mate distance for side with advantage depends of how fast (or slow) can get maximum pieces mobility.
I don't think any forced win (DTM for any TB) ever exceeds 1000 moves.
Even 594 is a very big number.
But i need a patience ... to get answer.
I guess that there is a forced mate with more than 1000 moves but
I think it may be better to see what happens in smaller boards than 8*8 first.
Do people know what is the maximal distance to mate in 3*3 board,3*4 boards,4*3 boards and 4*4 boards as a function of number of pieces?
My personal Opinion about the 8-piece endgame tablebases is that it will make weaker engines that are about 200 Elo weaker than Stockfish and Komodo Dragon to get more draws, and this will NOT reflect the true strength of the weaker engine in question because
every time that the position reach 8-pieces endgame the weaker engine will get the benefit of drawing instead of letting the two engines that are competing show why the are superior to the other engine. What will be the purpose of testing engines? To stop them once engine X reach a superior position over engine Y during the middlegame ?
I have another question how hard it is for most 3400 to 3450 engines to get positions that end up being 8-pieces, but because up to now since we did NOT have 8-pieces endgame, even if the weaker engine reached the 8 pieces position and it was superior for the weaker engine, Stockfish or Komodo Dragon had a chance to equalize by having more chess knowledge, but the 8 pieced endgame tablebase will make testing engines useless when they are rated only 100 to 150 Elo difference. Anyway most engine up to now have problem solving this position
Note: I hope that in tournaments they can allow two human players to use endgame book showing all the endgame positions up to 8-pieces and to play it against your stronger opponent. Example a 2200 Fide player playing versus a 2600 or 2700 will not have any problem drawing most games once they reach 8- pieces
Lazy_Frank wrote: ↑Thu Jun 16, 2022 2:54 pm
For me interesting is question: how long is longest forced win DTM for n-TB.
Someone may suggest: if 8-TB longest mate took 584 moves, then 9-TB can be ...
Yes, that is interesting, but we don't know what the longest 8-man mate is. The 8-man TBs that exist are only a small subset of all 8-man TBs (and I assume there's no current way for us to get access to those that exist).
Lazy_Frank wrote: ↑Thu Jun 16, 2022 2:54 pm
For me interesting is question: how long is longest forced win DTM for n-TB.
Someone may suggest: if 8-TB longest mate took 584 moves, then 9-TB can be ...
Yes, that is interesting, but we don't know what the longest 8-man mate is. The 8-man TBs that exist are only a small subset of all 8-man TBs (and I assume there's no current way for us to get access to those that exist).
8 pieces EGTB
As a result of these leaps and bounds it was speculated, understandably, that the longest mate with eight pieces might lead to solutions in excess of 1000 moves. However, Marc Bourzutschky has shared his findings with all the pawnless endgames and regrets to inform that the longest solution he found was a modest hop deeper with 584 moves. Lets say that it took between 40 to 50 moves to reach this position, then you have to add 584 Moves, and it will be the longest game ever played. It is Mate in 584 Moves! after you reach this position ==> https://en.chessbase.com/post/8-piece-e ... -interview
jp wrote: ↑Fri Jun 17, 2022 9:48 am
... we don't know what the longest 8-man mate is. The 8-man TBs that exist are only a small subset of all 8-man TBs...
<snip>
Again, we don't have all the 8-man TBs. Why assume all the ones we don't have won't have a longer mate?
P.S. It's hard to read your posts when you resort to huge font sizes, etc.
With these 8 piece egtb's is there anyone that can point me to the stat files that show all the details like how it was done for the 3-4-5-6-7 piece EGTB's?
I am interested in these details as I have been monitoring all the other egtb files.
vb4 wrote: ↑Mon Jun 20, 2022 9:36 pm
With these 8 piece egtb's is there anyone that can point me to the stat files that show all the details like how it was done for the 3-4-5-6-7 piece EGTB's?
I don't know about stat files and all details, but MB wrote this, giving a few details:
"The computer algorithm employed is standard retrograde analysis, but using various tricks, largely due to Yakov Konoval, to make the generation feasible for hobby computing. I use the Distance to Conversion (DTC) metric, which is the shortest number of moves to either checkmate or capture. The databases are one-sided, meaning they contain only wins for White and losses for Black. As a result, kxky and the “flipped” ending kykx are generally different. Endings of the form kkx are not needed because the number of White wins and Black losses would obviously be exactly zero. This results in 1,632 possible 8-piece configurations for pawnless endings, and a total of 4,795 configurations if pawns are included. I don’t consider castling rights and ignore the 50-move rule."
vb4 wrote: ↑Mon Jun 20, 2022 9:36 pm
With these 8 piece egtb's is there anyone that can point me to the stat files that show all the details like how it was done for the 3-4-5-6-7 piece EGTB's?
I am interested in these details as I have been monitoring all the other egtb files.
Thanks in advance Les
Because until now, every longest mate record came from pawnless endgames, so it is not unreasonable to assume the same holds true for 8 pieces. Of the pawnful 8-piece sets resolved and shared, none came close to challenging that 500+ move record.
"Tactics are the bricks and sticks that make up a game, but positional play is the architectural blueprint."
I am not sure that you are right and I found the following mate in 549 in the 7 piece lomosonov tablebases
Is there a longer mate with 7 pieces without pawns.
