AlphaZero No Castling Chess

[lkaufman]

I am on the phone and TeamViewer now, but the result with

Contempt = 75
White Contempt = True

is almost identical:

60+0.6
White wins: 99/200
Draws: 94/200
Black Wins: 7/200

The openings were built with the White Contempt = 50 (and no Black castling), so I would not worry too much about them. An interesting result, I guess a much larger White Contempt would even harm the White. So, Komodo seems to consider this a very simple and balanced Armageddon variant.

OK, so far quite remarkable that this ultra-simple rule could be so balanced. I downloaded your nbc book and will run my own tests on it; the big question is whether it will tilt too much one way with more time (although your forty games at 240 +2.4" said no). I can also test it on Komodo MCTS and on Stockfish (since Stockfish also has similar contempt settings); I guess there's less point to checking it out on Lc0 without a way to make it go for wins as White and draws as Black. I checked out the initial position with several engines. Komodo gives it a bit over +1, and SF about +1.3, both of which are well above what I consider the win/draw threshold on those engines (roughly 0.7 on K and 1.0 on SF). However the nn engines showed about 71% win prob. (72.5% for two top Lc0 networks, 69% for Fat Fritz), which is right about where the win/draw line should fall. I still think that in human play White will score well over 50%, but that is due to psychological reasons rather than objective ones; it's simply more fun to look for wins than to try to avoid them, and being unhappy is not conducive to best results. But we can't model this, so I think the best we can do is to hope that White scores a bit under 50% in engine play with more time, so that the human bias for pleasant positions won't give White too big a score in human play.

I tested at longer TC in 100 games overnight, it came completely even with 0 Black wins.

240+2.4
White wins: 50/100
Draws: 50/100
Black Wins: 0/100

One issue would be that these are self-plays of identical Komodos. But I think the performances being so stable with TC, even if strong humans would do better as White, the White performance would hover in human games at say 60% irrespective of time control and even strength (well, strong and very strong humans anyway).

I am now testing the resolving power of this simple variant pitting Komodo at 60+0.6 versus Komodo at 40+0.4, and comparing the result to standard chess result. Also, the White performance will be again interesting to see with these unequal opponents. Probably 400 games. Now I am controlling my PC remotely on the phone, so troubles copying and pasting here might occur.

I also ran it overnight, and my results agree remarkably well with yours. I used 300 +3", my I7 laptop runs at 4.9 Ghz (is yours also pretty fast?). My result was 106 White wins, 103 draws, 5 Black wins, so with Armageddon scoring 106 to 108. So no real trend for the results with more time, and the trivial Black win is at least in the direction I hoped, since White will probably do better in human play.

This is really remarkable. I gave up on the idea too quickly when I first thought of it because the SF and Komodo evals were too high, but it seems that they are just wrong. Looks like the NNs got it right. So we now have a variant of chess that appears to be perfectly balanced (at least between engines), has no draws, and can be explained in one short sentence ("Black cannot castle but wins draws"). I guess the NBC Armageddon name is the best one. The fact that Kramnik and AlphaZero have just promoted no castling chess in a big way makes this incredibly timely!

I'll have to test it with K mcts and with SF.

[lkaufman]

Of course. In Armageddon, the draw-rate is 0%, too. But NBC is a subset of chess. Black not to castle is very "unnatural".
In Blackmageddon, all castlings are allowed. So, it is quite normal chess. With white having one pawn less. Followed by 5 human opening-moves out of the Megabase. That is the reason, because a material advantage is so much better, than an advantage in castling-rights. The problem of Armageddon with one pawn more for white (I did that,too, called PawnPlus-Armageddon) is, that the advantage for white (first to move and one pawn ahead) is too big. So, I had the idea, to give black the material advantage instead (=Blackmageddon). So white has still the advantage of first to move and black has the advantage of the pawn more. That gives black a measureable advantage in each game, but it is smaller, than in PawnPlus-Armageddon. That makes the whitescore/blackscore-balance better and more stable.
And that is, why I believe, Blackmageddon is the best way to implement the Armageddon-concept in computerchess.

Here an example (opening 2 of Blackmageddon 500 file). All 4 castlings are still possible. So, playing this line will give a normal game of chess.

[pgn] [Event "Lugano ol (Men) fin-A"] [Site "Lugano"] [Date "1968.11.02"] [Round "9"] [White "Uhlmann, Wolfgang"] [Black "Bobotsov, Milko G"] [Result "1/2-1/2"] [ECO "D53"] [WhiteElo "2530"] [BlackElo "2455"] [Annotator "game 178, depth=26 val=-60 filter=[-60/-59] s"] [PlyCount "18"] [EventDate "1968.10.17"] [Source "ChessBase"] [SourceDate "1999.07.01"] 1. a4 Nc6 2. a5 Nxa5 3. Na3 Nc6 4. Nb1 Nb8 5. d4 Nf6 6. c4 e6 7. Nf3 d5 8. Nc3 Be7 9. Bg5 h6 1/2-1/2 [/pgn]

This is a variant of an idea I proposed a while ago. The difference is that I concluded that White would have to part with the b2,c2,d2, or e2 pawn to make Armageddon balanced; the engine evals with a2 missing are way below the normal win/draw threshold. But somehow your results show only a very mild White edge, I'll have to investigate why. My first suspicion as a GM is that the Queen's Gambit, as in your example above, is quite inappropriate without a pawn that can go to a3. With the "a" pawn missing, White wants to play c3 to keep a Black piece from outposting on b4. This is the problem with using normal openings from a non-normal start position. Maybe a lot of your openings include c4?.
As to whether players (both OTB and correspondence players) would prefer no castling or a missing pawn to compensate draw odds, my opinion is that most would accept no castling more readily than missing pawn. No castling requires the other side to attack, while missing pawn requires the superior side to trade down to an ending. Which game do you think is more appealing to the majority of chess players?
I do like the concept of pawn for Armageddon, but it looks like the second-best solution to me right now.

[lkaufman]

I am on the phone and TeamViewer now, but the result with

Contempt = 75
White Contempt = True

is almost identical:

60+0.6
White wins: 99/200
Draws: 94/200
Black Wins: 7/200

The openings were built with the White Contempt = 50 (and no Black castling), so I would not worry too much about them. An interesting result, I guess a much larger White Contempt would even harm the White. So, Komodo seems to consider this a very simple and balanced Armageddon variant.

OK, so far quite remarkable that this ultra-simple rule could be so balanced. I downloaded your nbc book and will run my own tests on it; the big question is whether it will tilt too much one way with more time (although your forty games at 240 +2.4" said no). I can also test it on Komodo MCTS and on Stockfish (since Stockfish also has similar contempt settings); I guess there's less point to checking it out on Lc0 without a way to make it go for wins as White and draws as Black. I checked out the initial position with several engines. Komodo gives it a bit over +1, and SF about +1.3, both of which are well above what I consider the win/draw threshold on those engines (roughly 0.7 on K and 1.0 on SF). However the nn engines showed about 71% win prob. (72.5% for two top Lc0 networks, 69% for Fat Fritz), which is right about where the win/draw line should fall. I still think that in human play White will score well over 50%, but that is due to psychological reasons rather than objective ones; it's simply more fun to look for wins than to try to avoid them, and being unhappy is not conducive to best results. But we can't model this, so I think the best we can do is to hope that White scores a bit under 50% in engine play with more time, so that the human bias for pleasant positions won't give White too big a score in human play.

I tested at longer TC in 100 games overnight, it came completely even with 0 Black wins.

240+2.4
White wins: 50/100
Draws: 50/100
Black Wins: 0/100

One issue would be that these are self-plays of identical Komodos. But I think the performances being so stable with TC, even if strong humans would do better as White, the White performance would hover in human games at say 60% irrespective of time control and even strength (well, strong and very strong humans anyway).

I am now testing the resolving power of this simple variant pitting Komodo at 60+0.6 versus Komodo at 40+0.4, and comparing the result to standard chess result. Also, the White performance will be again interesting to see with these unequal opponents. Probably 400 games. Now I am controlling my PC remotely on the phone, so troubles copying and pasting here might occur.

I also ran it overnight, and my results agree remarkably well with yours. I used 300 +3", my I7 laptop runs at 4.9 Ghz (is yours also pretty fast?). My result was 106 White wins, 103 draws, 5 Black wins, so with Armageddon scoring 106 to 108. So no real trend for the results with more time, and the trivial Black win is at least in the direction I hoped, since White will probably do better in human play.

This is really remarkable. I gave up on the idea too quickly when I first thought of it because the SF and Komodo evals were too high, but it seems that they are just wrong. Looks like the NNs got it right. So we now have a variant of chess that appears to be perfectly balanced (at least between engines), has no draws, and can be explained in one short sentence ("Black cannot castle but wins draws"). I guess the NBC Armageddon name is the best one. The fact that Kramnik and AlphaZero have just promoted no castling chess in a big way makes this incredibly timely!

I'll have to test it with K mcts and with SF.

Final result at 300 + 3 was 111 White wins, 108 draws, 5 Black wins, so still just 2 points more for Black (out of 224 games). Switched to MCTS Komodo, four threads at 1' + 0.6".

[pohl4711]

As to whether players (both OTB and correspondence players) would prefer no castling or a missing pawn to compensate draw odds, my opinion is that most would accept no castling more readily than missing pawn. No castling requires the other side to attack, while missing pawn requires the superior side to trade down to an ending. Which game do you think is more appealing to the majority of chess players?
I do like the concept of pawn for Armageddon, but it looks like the second-best solution to me right now.

Possible. But Blackmageddon is made for computerchess, not for humans. And for computerchess, a material imbalance is more natural and a more stable advantage, than forbidden castlings.
And in human tounaments, the best Armageddon is a time-handicap for black. Which is already used in playoffs today. No need for any Armageddon special-openings.

[Nordlandia]

Removing the rook-pawn provide some counter-compensation in forms of semi-open file.
I do think it's better to tradeoff armageddon with no castling privileges for the side with draw odds.

[Laskos]

As to whether players (both OTB and correspondence players) would prefer no castling or a missing pawn to compensate draw odds, my opinion is that most would accept no castling more readily than missing pawn. No castling requires the other side to attack, while missing pawn requires the superior side to trade down to an ending. Which game do you think is more appealing to the majority of chess players?
I do like the concept of pawn for Armageddon, but it looks like the second-best solution to me right now.

Possible. But Blackmageddon is made for computerchess, not for humans. And for computerchess, a material imbalance is more natural and a more stable advantage, than forbidden castlings.
And in human tounaments, the best Armageddon is a time-handicap for black. Which is already used in playoffs today. No need for any Armageddon special-openings.

No, time handicap is an unstable handicap with time control and strength for both humans and engines, one cannot ensure some fair scoring for say fixed 1:4 time handicap at every time control and on a wide range of strength.

[pohl4711]

As to whether players (both OTB and correspondence players) would prefer no castling or a missing pawn to compensate draw odds, my opinion is that most would accept no castling more readily than missing pawn. No castling requires the other side to attack, while missing pawn requires the superior side to trade down to an ending. Which game do you think is more appealing to the majority of chess players?
I do like the concept of pawn for Armageddon, but it looks like the second-best solution to me right now.

Possible. But Blackmageddon is made for computerchess, not for humans. And for computerchess, a material imbalance is more natural and a more stable advantage, than forbidden castlings.
And in human tounaments, the best Armageddon is a time-handicap for black. Which is already used in playoffs today. No need for any Armageddon special-openings.

No, time handicap is an unstable handicap with time control and strength for both humans and engines, one cannot ensure some fair scoring for say fixed 1:4 time handicap at every time control and on a wide range of strength.

But this is the way Armageddon is played by humans. But who cares? I built Blackmageddon for computerchess. And there, a time-handicap is definitly not working.

[lkaufman]

As to whether players (both OTB and correspondence players) would prefer no castling or a missing pawn to compensate draw odds, my opinion is that most would accept no castling more readily than missing pawn. No castling requires the other side to attack, while missing pawn requires the superior side to trade down to an ending. Which game do you think is more appealing to the majority of chess players?
I do like the concept of pawn for Armageddon, but it looks like the second-best solution to me right now.

Possible. But Blackmageddon is made for computerchess, not for humans. And for computerchess, a material imbalance is more natural and a more stable advantage, than forbidden castlings.
And in human tounaments, the best Armageddon is a time-handicap for black. Which is already used in playoffs today. No need for any Armageddon special-openings.

No, time handicap is an unstable handicap with time control and strength for both humans and engines, one cannot ensure some fair scoring for say fixed 1:4 time handicap at every time control and on a wide range of strength.

But this is the way Armageddon is played by humans. But who cares? I built Blackmageddon for computerchess. And there, a time-handicap is definitly not working.

So far time-handicap has never been used in human play for Armageddon at time limits where one side gets standard tournament time (like 2 hours on 90 min plus 30 sec inc), only fast games. But anyway we all agree that for Armageddon to work best, the offset needs to be on the board, whether an extra pawn, extra tempi, or castling rights, or just bad openings for the side with draw odds. The question is which way works best.

[Laskos]

I am on the phone and TeamViewer now, but the result with

Contempt = 75
White Contempt = True

is almost identical:

60+0.6
White wins: 99/200
Draws: 94/200
Black Wins: 7/200

The openings were built with the White Contempt = 50 (and no Black castling), so I would not worry too much about them. An interesting result, I guess a much larger White Contempt would even harm the White. So, Komodo seems to consider this a very simple and balanced Armageddon variant.

OK, so far quite remarkable that this ultra-simple rule could be so balanced. I downloaded your nbc book and will run my own tests on it; the big question is whether it will tilt too much one way with more time (although your forty games at 240 +2.4" said no). I can also test it on Komodo MCTS and on Stockfish (since Stockfish also has similar contempt settings); I guess there's less point to checking it out on Lc0 without a way to make it go for wins as White and draws as Black. I checked out the initial position with several engines. Komodo gives it a bit over +1, and SF about +1.3, both of which are well above what I consider the win/draw threshold on those engines (roughly 0.7 on K and 1.0 on SF). However the nn engines showed about 71% win prob. (72.5% for two top Lc0 networks, 69% for Fat Fritz), which is right about where the win/draw line should fall. I still think that in human play White will score well over 50%, but that is due to psychological reasons rather than objective ones; it's simply more fun to look for wins than to try to avoid them, and being unhappy is not conducive to best results. But we can't model this, so I think the best we can do is to hope that White scores a bit under 50% in engine play with more time, so that the human bias for pleasant positions won't give White too big a score in human play.

I tested at longer TC in 100 games overnight, it came completely even with 0 Black wins.

240+2.4
White wins: 50/100
Draws: 50/100
Black Wins: 0/100

One issue would be that these are self-plays of identical Komodos. But I think the performances being so stable with TC, even if strong humans would do better as White, the White performance would hover in human games at say 60% irrespective of time control and even strength (well, strong and very strong humans anyway).

I am now testing the resolving power of this simple variant pitting Komodo at 60+0.6 versus Komodo at 40+0.4, and comparing the result to standard chess result. Also, the White performance will be again interesting to see with these unequal opponents. Probably 400 games. Now I am controlling my PC remotely on the phone, so troubles copying and pasting here might occur.

I also ran it overnight, and my results agree remarkably well with yours. I used 300 +3", my I7 laptop runs at 4.9 Ghz (is yours also pretty fast?). My result was 106 White wins, 103 draws, 5 Black wins, so with Armageddon scoring 106 to 108. So no real trend for the results with more time, and the trivial Black win is at least in the direction I hoped, since White will probably do better in human play.

This is really remarkable. I gave up on the idea too quickly when I first thought of it because the SF and Komodo evals were too high, but it seems that they are just wrong. Looks like the NNs got it right. So we now have a variant of chess that appears to be perfectly balanced (at least between engines), has no draws, and can be explained in one short sentence ("Black cannot castle but wins draws"). I guess the NBC Armageddon name is the best one. The fact that Kramnik and AlphaZero have just promoted no castling chess in a big way makes this incredibly timely!

I'll have to test it with K mcts and with SF.

With SF and Lc0 there is an issue that they have no Colored Contempt. Lc0 has no Contempt at all and from my past experience, doesn't excel in variants deviating from Chess, although here the deviation is small. For SF I used the default Contempt, setting it much higher will make Black chasing wins only too, which is bad. I got very similar result (I even wonder how all these results fall very close one to another, not much of even statistical fluctuations):

200 games at 60 + 0.6, SF self-play, default Contempt, NBC_473 suite:

White wins: 98
Draws: 96
Black Wins: 6

This thing seems remarkably stable. In my patzer view, without any "tradition" in playing serious Chess, this variant seem better than Chess .
Isn't it exciting? No draws. White cannot "play safe" like the usual "if not a win, a draw will do", and Black finding itself in constant danger, having to play very accurately and neutralize White. Asymmetry is also appealing, especially in side and reversed, to show different faces of the players. But side and reversed seems to not even be more necessary than in regular Chess, as the Armageddon score is close enough to 50% for equal players both sides (55% for White in regular Chess). Just ensure that overall in the tournament, the player gets a fair amount of White and Black.

Hope that these experiments hold in human games, where the psychology is a large factor. I guess the level of playing of Komodo and SF at these time controls is quite high, but top humans can develop an opening theory for this variant well beyond the opening play of the engines at short tc, and get a bit different view, aside psychological factors like the taste for playing as White.

Also to note that NBC Armageddon has a binomial type scoring, but side and reversed, a trinomial variance can be applied to pairs of games (0,1,2 results in pairs of games for one of the players), especially in engine matches, which will reduce significantly the error margins for these unbalanced openings. The resolving power of NBC Armageddon seems significantly higher than that of regular Chess.

[Nordlandia]

Engines need to know that they're playing armageddon. So they need to be taught playing that mode.