RSIF as alternative to armageddon

[lkaufman]

Well, we know that fifty isn't enough for a lot of endings. Probably if my rules were to be adopted, we should either raise the 50 (perhaps to 75), or else list some exceptions where the number might go up to 100, like they used to do before the computers got involved.

[Ferdy]

Neat idea - I'll try to play a few games with friends who like variants.

What happens if two conflicting conditions occur on the same move?

For example, here, after black plays 1... Rc6, white plays 2. Nxc6, resulting in both stalemate and insufficient material.

[d]k1r5/8/1K6/4N3/8/8/8/8 b - - 0 1


Repetition and 50 move rule could also be triggered at the same time, as can stalemate and the 50 move rule.

I suppose it's not possible to trigger repetition and insufficient material at the same time, though, as reducing to insufficient material implies a capture, which cannot be repeated.

I have not thought such conflict of interests, but I think after white's Nxc6, white can decide for stalemate or insufficient.

In case of repetition and fifty, the player that made the last move can also decide if it is repetition or fifty. So generally the player that made the last move will decide.

Deuterium rsif is not optimized on those specific rules. Will make some modification and try another tests.

[Ozymandias]

1. Three time repetition is illegal.
2. Stalemate is a loss for the stalemated side. (old rule)
3. Bare King loses. (old rule)
4. Fifty move rule is a win for Black.

1. Agreed, I don't even see the reason for the 1st and 2nd repetition, but the less is changed the better, I guess.
2. Obviously. Although equalling a mate and a stalemate isn't completely fair. I would place it halfway 0.75-0.25.
3. Agreed too, no all material advantages are the same, but why quibble.
4. I can't agree with that, at least for engine play, where you may have a mating sequence well in excess of 50 moves.

[jp]

4. Fifty move rule is a win for Black.

4. I can't agree with that, at least for engine play, where you may have a mating sequence well in excess of 50 moves.

Yeah, you could have an engine with tablebases announce mate in 300 and resign simultaneously.

[Ovyron]

Okay, just want to make people aware of these possibilities that can be tested and mixed in the optimal solution (some of them exclude each other):

-Player repeating a position three times wins
-Player repeating a position three times loses
-Player reaching a position with insufficient material to mate either side wins
-Player reaching a position with insufficient material to mate either side loses
-Player stalemating opponent loses
-If no pawn move or capture happens after N moves, the last player making a capture/pawn move on the game wins
-If no pawn move or capture happens after N moves, the last player making a capture/pawn move on the game loses
-Stalemating opponent is illegal
-Reaching a position with insufficient material to mate either side is illegal
-If no pawn or capture happens after N moves, playing a move is illegal

(these last two just mean stalemate rules, whatever they are, are applied to N moves without capture/pawn move)

Splitting hair ideas (I know they look like a joke, but could be worthy of examination)
-If no pawn move or capture happens after N moves, the last player making a capture in the game wins
-If no pawn move or capture happens after N moves, the last player making a capture in the game loses
-If no pawn move or capture happens after N moves, the last player making a pawn move in the game wins
-If no pawn move or capture happens after N moves, the last player making a pawn move in the game loses

[lkaufman]

4. Fifty move rule is a win for Black.

4. I can't agree with that, at least for engine play, where you may have a mating sequence well in excess of 50 moves.

Yeah, you could have an engine with tablebases announce mate in 300 and resign simultaneously.

The rule could be that if there is a tablebase win then the fifty move rule becomes tablebase moves + 10 (to allow for engines without TBs or human play). Maybe FIDE should adopt this rule? But to be totally correct, someone would have to redo tablebases to be consistent with my stalemate/bare king rule. If White has no forced checkmate but can force stalemate in 75 moves, he should still get the win logically. This would help a little towards equalizing the game, since probably Black has some advantage overall with my rules. Or we could just raise 50 to 75, which should cover most cases.

[Ozymandias]

someone would have to redo tablebases to be consistent with my stalemate/bare king rule. [...] This would help a little towards equalizing the game, since probably Black has some advantage overall with my rules.

If syzygy doesn't offer a win in sight, it will only provide draw suggestions, a modified engine would then pick those with a better chance of leading to a stalemate/bare king situation, without precluding the possibility of a real win. Changing tablebases would make these semi-wins undistinguishable from actual wins. The point should be to reduce the number of draws, not to inflate the number of wins.

Rule 4 evidently favours black, but I don't see how the other three would. BTW, keeping with the goal of avoiding draws, while being impartial, the fifty move rule should behave the same as the 3-fold, the side to make the 50th loses.

[lkaufman]

someone would have to redo tablebases to be consistent with my stalemate/bare king rule. [...] This would help a little towards equalizing the game, since probably Black has some advantage overall with my rules.

If syzygy doesn't offer a win in sight, it will only provide draw suggestions, a modified engine would then pick those with a better chance of leading to a stalemate/bare king situation, without precluding the possibility of a real win. Changing tablebases would make these semi-wins undistinguishable from actual wins. The point should be to reduce the number of draws, not to inflate the number of wins.

Rule 4 evidently favours black, but I don't see how the other three would. BTW, keeping with the goal of avoiding draws, while being impartial, the fifty move rule should behave the same as the 3-fold, the side to make the 50th loses.\

White has a big advantage in normal chess, the idea is that with the other types of draws being called wins for one side or the other, the fifty move rule draws being awarded to Black (or 75 move, or whatever) might make chess a roughly fair game with no draws. I suspect that there would still be too many of these fifty move "draws" being awarded to Black to make it fair, but I'm not certain.

[Ozymandias]

someone would have to redo tablebases to be consistent with my stalemate/bare king rule. [...] This would help a little towards equalizing the game, since probably Black has some advantage overall with my rules.

If syzygy doesn't offer a win in sight, it will only provide draw suggestions, a modified engine would then pick those with a better chance of leading to a stalemate/bare king situation, without precluding the possibility of a real win. Changing tablebases would make these semi-wins undistinguishable from actual wins. The point should be to reduce the number of draws, not to inflate the number of wins.

Rule 4 evidently favours black, but I don't see how the other three would. BTW, keeping with the goal of avoiding draws, while being impartial, the fifty move rule should behave the same as the 3-fold, the side to make the 50th loses.\

White has a big advantage in normal chess, the idea is that with the other types of draws being called wins for one side or the other, the fifty move rule draws being awarded to Black (or 75 move, or whatever) might make chess a roughly fair game with no draws. I suspect that there would still be too many of these fifty move "draws" being awarded to Black to make it fair, but I'm not certain.

The only one of those rules that I can recall ever being tested, was the stalemate one, and it had very little effect. At the level engines play now, I doubt that even all of them combined would make much of a difference. Rule 4 favouring black might make enough of an impact, it might be worth testing, but as far reducing draws, the loss being for the side that makes the 50th move should help more. After all, the side that's in a bad position is the one that doesn't want to introduce changes.

[Ferdy]

Neat idea - I'll try to play a few games with friends who like variants.

What happens if two conflicting conditions occur on the same move?

For example, here, after black plays 1... Rc6, white plays 2. Nxc6, resulting in both stalemate and insufficient material.

[d]k1r5/8/1K6/4N3/8/8/8/8 b - - 0 1


Repetition and 50 move rule could also be triggered at the same time, as can stalemate and the 50 move rule.

I suppose it's not possible to trigger repetition and insufficient material at the same time, though, as reducing to insufficient material implies a capture, which cannot be repeated.

I have not thought such conflict of interests, but I think after white's Nxc6, white can decide for stalemate or insufficient.

In case of repetition and fifty, the player that made the last move can also decide if it is repetition or fifty. So generally the player that made the last move will decide.

Deuterium rsif is not optimized on those specific rules. Will make some modification and try another tests.

Implemented the conflict on stalemate and insufficient mating material rules. The player that played the last move will decide if it is stalemate or insufficient.

Test 1:
k7/8/1Kr5/4N3/8/8/8/8 w - - bm Nxc6; c0 "win in 1 move via rsif stalemate wins for white";
White should play the bm to win the game.

[d]k7/8/1Kr5/4N3/8/8/8/8 w - - 0 1
Deuterium rsif

Code: Select all

position fen k7/8/1Kr5/4N3/8/8/8/8 w - - 0 1
go movetime 50
info depth 1 seldepth 4 multipv 1 score cp -478 time 1 nodes 23 nps 23000 pv b6a5 c6c5 a5b4 c5e5
info depth 2 seldepth 4 multipv 1 score mate 1 time 18 nodes 44 nps 2444 pv e5c6
info depth 2 seldepth 3 multipv 1 score mate 1 time 28 nodes 54 nps 1928 pv e5c6
info depth 3 seldepth 2 multipv 1 score mate 1 time 33 nodes 60 nps 1818 pv e5c6
info depth 4 seldepth 5 multipv 1 score mate 1 time 36 nodes 83 nps 2305 pv e5c6
info depth 5 seldepth 5 multipv 1 score mate 1 time 39 nodes 114 nps 2923 pv e5c6
info depth 6 seldepth 6 multipv 1 score mate 1 time 42 nodes 147 nps 3500 pv e5c6
info depth 7 seldepth 6 multipv 1 score mate 1 time 45 nodes 179 nps 3977 pv e5c6
info depth 8 seldepth 6 multipv 1 score mate 1 time 47 nodes 212 nps 4510 pv e5c6
info time 54 nodes 213
bestmove e5c6

Test 2:
k1r5/8/1K6/4N3/8/8/8/8 b - - am Rc6+; c0 "After Nxc6 black cannot claim insufficient mating material rule because white will claim first stalemate which is a win for white";
Black should not play Rc6+.

[d]k1r5/8/1K6/4N3/8/8/8/8 b - - 0 1
Deuterium rsif

Code: Select all

position fen k1r5/8/1K6/4N3/8/8/8/8 b - - 0 1
go movetime 50
info depth 1 seldepth 2 multipv 1 score cp 20 time 1 nodes 20 nps 20000 pv a8b8
info depth 2 seldepth 5 multipv 1 score cp 19 time 15 nodes 100 nps 6666 pv a8b8 b6b5
info depth 3 seldepth 5 multipv 1 score cp 21 time 15 nodes 394 nps 26266 pv c8e8 e5f3 a8b8
info depth 4 seldepth 7 multipv 1 score cp 19 time 31 nodes 1168 nps 37677 pv c8c1 e5d3 c1b1 b6c6 a8b8
info depth 5 seldepth 8 multipv 1 score cp 21 time 31 nodes 1801 nps 58096 pv c8c1 e5d3 c1c6 b6b5 a8b7
info depth 6 seldepth 10 multipv 1 score cp 21 time 31 nodes 3300 nps 106451 pv c8b8 b6c6 b8b6 c6c7 a8a7 e5d7 b6c6 c7d8
info depth 7 seldepth 10 multipv 1 score cp 23 time 31 nodes 5970 nps 192580 pv c8c5 e5f3 c5c6 b6b5 a8b7 f3d4 c6c8
info depth 8 seldepth 11 multipv 1 score cp 23 time 46 nodes 7353 nps 159847 pv c8c5 e5f3 c5c6 b6a5 a8b7 a5b5 c6c8 f3d4
info depth 9 seldepth 12 multipv 1 score cp 25 time 46 nodes 11313 nps 245934 pv c8c5 e5d3 c5c6 b6b5 a8b7 b5b4 c6c4 b4b5 c4c5 b5b4 c5c6
info time 62 nodes 11324
bestmove c8c5