bnemias wrote:The wider TCEC solution isn't so clear because it is possible to have one engine using Gaviota while the other is using Syzygy (or no TB). Luckily we don't have that case, because I doubt it is possible to adjudicate that case fairly under the current rules.
Nonsense. Syzygy is always right as far as I know. Gaviota can be wrong. If an engine uses Gaviota it has to expect it being wrong sometimes.
Not nonsense. The point you are making is very debatable, because it depends if you want to apply the 50 move rule to these games. That question is a different matter, and frankly, I'm not even sure where I stand on it. But that's another thread.
[edit] nvm. I get where you are coming from after rereading your post. Yeah, if you accept that the tournament adheres to the 50 move rule, then Gaviota is indeed sometimes wrong.
Last edited by bnemias on Thu Nov 17, 2016 3:28 am, edited 1 time in total.
I consider the rule "defective" in the sense that it deviated from its purpose. Its purpose was to determine the natural outcome without intervention, and impose that outcome to save time. Instead of determining the natural outcome that the engines would eventually determine on their own, it imposed a different outcome.
I especially enjoy fights 1 vs 20 or 30, usually come on top, and usually that means I am rigth.
I have never until now seen so many low-thinking people posting into a single thread. Really astounding! I think the probability this actually happens is somewhere 1 to a zillion, so we have just witnessed an extraordinary phenomenon.
The easiest thing to do to resolve the situation is of course for engines to implement a more general fortress draw rule, for example in the following way:
int fdr=0; // fortress draw rule
makemove(); fdr++; if (move(capture) || move(promotion) || move(pawnmove) || move(castling) ) fdr=0;
void fdrule() // subroutine for fortress draw rule scoring
{if (pawncount(myside)==0 && pawncount(opponentside)==0)
{if (fdr>=200) score=0;} // providing for 70% of the most common endgames falling under that rule, but if you want, as Greg pointed, you might go as far as 1100
else {if (fdr>=100) score=0;}
}
I guess with a similar code the problem is easily solved. Interesting, who will be the first author to implement such a change in his engine?
Concerning the real TCEC game, this is quite similar to FIDE rules concerning the situation when a player has been flagged, but he has just delivered his opponent a mate. In this case, although the flag of the player is already down, thus losing on time, he still wins the game, fully according to FIDE rules, as there is mate on the board, which overrides flagging.
Very similarly, based on TCEC special draw rule, the game was declared drawn, but, when Cutechess adjudicated the tablebase position, it adjudicated a win, as the position is simply won. An existing win on the board, which is the case in current game, actually an existing mate, certainly overrides the special TCEC draw rule.
A win is a win, that is very simple, it would be more than a sin to adjudicate a winning position as a draw.
Lets make an absurd example to show the point. I play GM Carlsen a 6 game match with 6 fixed and very unsound openings. So unsound I am able to win with white every game. And so is GM Carlsen.
And that is exactly what is not happening in TCEC.
I respect your opinion.
And I will let TCEC make my point.
It is not an opinion but a fact. There have not been any 1-1 openings so far.
Of course we might yet get openings that are so advantageous for one side that 1-1 is inevitable. But as hgm explained, even if that happens there is no damage. It will be as if TCEC had one round less. There would be no actual skew.
Sven Schüle wrote:For the future I suggest to add a clarification to the rules saying that adjudicating a position as a TB win will be skipped if the shortest mate is not possible within the 50-moves rule.
How are you going to manage that? Cutechess does seem to have Syzygy support started, but it is still unreleased as far as I can tell.
I wrote "for the future", not for the current TCEC season. That should be possible. Of course following my suggestion would require appropriate tool support.
Lets make an absurd example to show the point. I play GM Carlsen a 6 game match with 6 fixed and very unsound openings. So unsound I am able to win with white every game. And so is GM Carlsen.
And that is exactly what is not happening in TCEC.
I respect your opinion.
And I will let TCEC make my point.
It is not an opinion but a fact. There have not been any 1-1 openings so far.
Of course we might yet get openings that are so advantageous for one side that 1-1 is inevitable. But as hgm explained, even if that happens there is no damage. It will be as if TCEC had one round less. There would be no actual skew.
I have shown here: http://www.talkchess.com/forum/viewtopi ... 45&start=0
that borderline, unbalanced openings (roughly 50% White wins and 50% draws, with very few Black wins) are more sensitive in discerning the strength difference, especially in TCEC conditions, where the draw rate from balanced openings can reach 90%. In both BayesElo and Davidson draw models. TCEC is right using unbalanced positions.
ICCF adjudicates positions as won once a Tablebase is reached even if the moves required to win are more than 50 - implying FIDE rules of chess have been overridden in Correspondence Chess. Computer chess should also follow similar principles (though the TCEC rules are ambiguous in the current scenario)
bnemias wrote:The wider TCEC solution isn't so clear because it is possible to have one engine using Gaviota while the other is using Syzygy (or no TB). Luckily we don't have that case, because I doubt it is possible to adjudicate that case fairly under the current rules.
Nonsense. Syzygy is always right as far as I know. Gaviota can be wrong. If an engine uses Gaviota it has to expect it being wrong sometimes.
I think the point is that an engine using Gaviota might bungle a win that it gets awarded by adjudication with syzygy.
Note that the WinBoard method for quickly ending games that reached the EGT stage would not suffer from that. It would allow the Gaviota-using engine to bungle the win.
