Checkers Is Strongly-Solved for 8-pieces

[Rochester]

Perhaps you are unaware that the poster you replied to improved compression of chess DTZ databases by more than most people would have believed possible?

He unaware this is are also the chess forums. The chess people know more better than the checkers.

Then also...

... the indexers are the maddest ones.

[Ed Trice]

Perhaps you are unaware that the poster you replied to improved compression of chess DTZ databases by more than most people would have believed possible?

I compressed the 8-piece database more than any other available program, with the ratio of over 30 positions per byte.

http://worldchampionshipcheckers.com/db ... isons.html

So, yeah, I know about compression.

I also solved checkmate in 268 for Queen + Pawn vs. Queen on an 80-square board, so I don't need any "lessons" from the peanut gallery.

The purpose of this thread was to ANNOUNCE an accomplishment, and the pissants showed up trying to discredit it.

You can all go to hell if that's your stance.

[Dirt]

The purpose of this thread was to ANNOUNCE an accomplishment ...

Yes, thank you.

I've learned a bit both from you and from your interlocutors. One point is that there isn't a rule in checkers similar to the 50 move rule in chess, so all the talk about DTZ tables is weird.

[Rein Halbersma]

The purpose of this thread was to ANNOUNCE an accomplishment ...

Yes, thank you.

I've learned a bit both from you and from your interlocutors. One point is that there isn't a rule in checkers similar to the 50 move rule in chess, so all the talk about DTZ tables is weird.

There is such a rule, which differs for each checkers variant. For 8x8 checkers, mostly played in the US/UK, there is a 40 move rule (80 ply). For 10x10 draughts, mostly played in the Netherlands, France, Russia and formerly French Africa, the rule is 25 moves without conversion (50 ply) until a draw.

sources:
http://www.usacheckers.com/rulesofcheckers.php
http://www.fmjd.org/docs/Annex%201%20of ... aughts.doc

[Dirt]

I've learned a bit both from you and from your interlocutors. One point is that there isn't a rule in checkers similar to the 50 move rule in chess, so all the talk about DTZ tables is weird.

There is such a rule, which differs for each checkers variant. For 8x8 checkers, mostly played in the US/UK, there is a 40 move rule (80 ply). For 10x10 draughts, mostly played in the Netherlands, France, Russia and formerly French Africa, the rule is 25 moves without conversion (50 ply) until a draw.

sources:
http://www.usacheckers.com/rulesofcheckers.php
http://www.fmjd.org/docs/Annex%201%20of ... aughts.doc

What you have posted is quite official looking, but there seems to be many official rules for checkers.

[mar]

I remember as kids we used to play a checkers variant with two rows only (using standard chess pawns as checkers).
While the game is certainly interesting, I personally prefer chess.

However even orthodox chess can start to be boring at some point.

Recently I watched a guy who calls himself Jann Lee play crazyhouse and I have to say it's a very interesting variant (I would say way more than chess).
It's not as exotic as other variants which makes it easier for me to follow (bughouse is too difficult for me).

Lots of sacs, lot of crazy tactics and to me significantly more fun than chess, a way more dynamic game.

[Ed Trice]

However even orthodox chess can start to be boring at some point.

That's why I invented Gothic Chess. I had read both Henry Bird (1874) and Jose Capablanca (1921) tried to convince the world to change chess to an 80-square board with two new pieces: An Archbishop (knight + bishop) and Chancellor (knight + rook). They both had the right idea, but I believe they did not play-test it enough. Their starting positions each had one or more flaws.

1. Not all pawns were protected in each of their versions.
2. In Bird's game, Chancellor-to-h2 threatens Cxh7 mate! So much for making the opening more diverse.
3. Capablanca's game had Bishop, Queen, and Archbisop, 3 "diagonal-moving" pieces in a row, all on the Queenside, all aimed towards i7, and undefended pawn equivalent to g7 in regular chess.

After much play-testing, I found a more fluent setup.

I have a GUI that plays the game with 5-piece tablebases generator if you have 30 days and would like to see the Mate in 268 endgame.

https://drive.google.com/file/d/0BzeUnP ... sp=sharing

Here's what it looks like:

[Ed Trice]

A better view of the longest win with 4 checkers vs. 4 checkers and white to move.

[Daniel Anulliero]

I'm just a chess programmer ( the last one Isa is only 2165 CCRL) , and I've studied Othello game too , never the checkers
So excuse my ignorance but sure you did a great work, but with chinook , the game is solved it seems and chinook has
"an opening book, a library of opening moves from games played by grandmasters; a deep search algorithm; a good move evaluation function; and an end-game database for all positions with eight pieces or fewer."
(Read from wikipedia)
So I think it's a lot useless to work on a solved game , like I write an endgame database for Othello since the Bests programs can compute 30-40 moves in a few time.
Just my personnal réflexion ..
Bests
Dany

[abulmo2]

like I write an endgame database for Othello since the Bests programs can compute 30-40 moves in a few time.

To be more precise:
Endgame databases are not computed at Othello, because it is a diverging game. Endgame database are only usable on converging games, like chess or checkers.
Endgame are easily solved at Othello, because the game has a fixed termination, unlike chess.