Cheating suspicion at the Zadar Open in Croatia

[noctiferus]

Thx, Gabor, I see the plan: I thought that Nf5 would have come more natural (at least to me), freeing the way to the rook.
About the reason for black not resigning, I suspect there was some grudge, as can be read in italian chess review...

[Hood]

I have read that Ivanov won a rapid tournament. I do not believe he was cheating. Tempo is too quick to use aid of an external computer.

I do not believe statistics in such a cases.
Last time i read comments about Anand Topalov game that Anand made moves like Houdini choices! does it mean he is cheating too.

It is possible that player taught by chessprogram adapts his way of playing.

Paranoia are such open discussions on the theme.

Simlar discussions were about Rybka vs Ippolit and at the end Fruit issue has appeared.

[carldaman]

I was doing my home work, as promised to Adam, when I stepped into a unexplicable move (at least, for a patzer like me).
It was a game in Tarnovo "Old Capital" tournament, 2013, played between Ivanov and IM A.Rombaldoni.


Under hypothesis 1 (Ivanov is cheating) what happened? transmisstion problems? Wrong understanding of audio transmission?
Under hypothesis 2 (Ivanov not cheating) how it is possible? Not even a patzer like me would give such a pawn for nothing...

I would really appreciate your opinion. Thx.

It is very plausible that Nc6 was mistaken for the better Ng6 (+). Something could easily get lost in transmission...

[carldaman]

Thx, Gabor, I see the plan: I thought that Nf5 would have come more natural (at least to me), freeing the way to the rook.
About the reason for black not resigning, I suspect there was some grudge, as can be read in italian chess review...

Probably wise that he did not resign early, as playing on could reveal more engine-like moves. Engines often play vastly different moves than humans in winning positions.

[Sven]

Under hypothesis 2 (Ivanov not cheating) how it is possible? Not even a patzer like me would give such a pawn for nothing...

Clearly Nc6 misses an "easier" win as it has been shown, e.g. by f5 or Ng6+, but with Nc6 the Pd7 is not given "for nothing". If am not mistaken then White can capture on a5 after 1.Nc6 Bxd7: 2.Nxa5 Rxa5 (?) 3.Re7 Ra7 (3...Bc6 4.Rc7) 4.c5 Rb7 5.a5. Of course black does not need to take the knight on a5.

This is only one of many possible ways to win. Humans also have different criteria to choose a move, often they tend to simplify the game instead of complicating it. Trading an advanced passer on d7 that can't be protected sufficiently against a different advantage, like getting three connected passers, is quite "human" as well for me.

So in my eyes Nc6 is perfectly understandable, even if Ng6+ simply wins more material and may be "much easier" to win.

Sven

[Rebel]

Living in a world of multiple proven cheating cases every exceptional tournament performance immediately is highlighted as suspect.

Regarding the above I like to add one more thought.

Collect cases of exceptional tournament performances (like the Ivanov case) before the days cheating with chess programs made sense. Back then they were accepted without criticism and if only one shows a similar behavior as in the Ivanov case then the accusation is baseless.

[Don]

Living in a world of multiple proven cheating cases every exceptional tournament performance immediately is highlighted as suspect.

Regarding the above I like to add one more thought.

Collect cases of exceptional tournament performances (like the Ivanov case) before the days cheating with chess programs made sense. Back then they were accepted without criticism and if only one shows a similar behavior as in the Ivanov case then the accusation is baseless.

Before someone is accused I personally believe the evidence needs to be strong before the ball even starts to roll. But I don't think it has to proved first, otherwise there could never be any justice. How could those who would do damage to you and your family ever be convicted of crimes without them first being a suspect?

For the protection of the person being accused as well as the victims you must use a measured approach. You start with the suspicion (accusation) and the final point ends with a proof and a conviction.

Now you say the accusation is baseless, but I think you used the wrong word here. There is certainly enough evidence to raise significant suspicion, even though it's not a proof. Even if it turns out that Ivanov was not cheating it doesn't mean the accusations were baseless, it simply means Ivanov was not cheating! In a court trial there is always a hearing which determines if there is enough basis for a trial. The hearing is not to determine innocence or guilt and if the person is found innocent it doesn't mean the trial had no basis.

There are times when people are asked to leave their homes due to an impending disaster such as a hurricane. Sometimes the hurricane changes course and doesn't even touch the area. Would you consider this a "baseless" warning? I certainly wouldn't.

I'm actually doing my own study of the moves of thousands of games to compare them with the moves of a strong chess program. I am using Houdini 3 for this because it's currently the strongest and would be the one most likely to be used in cheating. Here are my preliminary findings:

The average match rate to Houdini 3 is about 56%. I consider a move to match Houdini if Houdini likes the move at any depth beyond 10 ply up to the amount of time I test which is just a few seconds per position. Not all the games are Grandmaster games but there is a mixture of different levels. It looks like almost all of them are at least master level with many GM games and a few in the expert range.

At the 95 percentile point we see a match rate of about 79% - most of the ones from that point on however have very few samples, in other words the games were short and only a few moves were available to be compared. I started at move 8 to avoid some of the opening preparation where matching becomes irrelevant.

There are a few outstanding match rates. 14 games matched 100% with Houdini, but only 1 to 5 positions were matched so that is not odd. The one exception was a match rate of 100% with 12 moves.

There is nothing between 90% and 100% for some odd reason I don't understand but from 79% to 88% it is fairly smooth. The 95 percentile and beyond only represent 58 total player instances.

I have not run the Zadar games using my match criteria but I want to avoid doing that till the end. I did however run the recent tournament which I think Ivanov won or had a very strong performance in but I don't really know how to interpret the results yet. All the games show a match percentage well above the average but at least until I can do more analysis I don't see anything that would make me suspicious. His best match rate in a single game was exactly 80% over 25 moves which is quite high but still only at the 95 percentile mark and the others range from a low of 61.54% to 76.19 percentage.

I want to do a lot more things such as a further analysis to see if the strongest players match significantly better than the weaker ones. It's not a given because we have already seen that playing style is only weakly correlated with strength. Even in the last 5 percentile (95 percentile and above) there were low rated players and in fact the mix of player ELO's seemed fairly well distributed. So an admittedly superficial analysis is not showing that strong players are more likely to match Houdini's moves but I should know more later.

Don

[Uri Blass]

I was doing my home work, as promised to Adam, when I stepped into a unexplicable move (at least, for a patzer like me).
It was a game in Tarnovo "Old Capital" tournament, 2013, played between Ivanov and IM A.Rombaldoni.

[d]r6k/3PN1pp/8/p7/P1P2PbP/1P4P1/8/4R1K1 w - - 0 42"


While before this move, Ivanov's performance was, as almost always, at the best of Houdini 2.0c (details will follow), here he plays Nc6.
While, before this move, he was playing first or second Houdini's moves, this one is below the 25th at depth 18, up to at least depth 20 (stopped here).

Actually, Houdini's suggestions were (depth 18)
Houdini 2.0c x64: 1)} 42. f5 Rf8 43. Ng6+ hxg6 44. Re8 Kg8 45. d8=Q Rxe8 46.
Qxe8+ Kh7 47. Qxg6+ Kh8 48. Qxg4 Kg8 49. f6 Kf7 50. fxg7 Ke7 51. g8=Q Kd6 52.
Q8c8 Ke5 53. Qce6# {[%eval 32755,19]})
({Houdini 2.0c x64: 2)} 42. Nf5 Bh5 43.g4 Bg6 44. Ne7 Be8 45. dxe8=R+ Rxe8 46. Ng6+ Kg8 47. Rxe8+ Kf7 48. Rf8+ Ke6 49.
Ne5 h6 50. Kf2 Kd6 51. Rg8 g5 52. hxg5 hxg5 53. Rxg5 Kc5 54. Nf3+ Kb6 55. Rb5+
Kc7 56. Rxa5 Kd8 57. Rd5+ Kc7 {[%eval 1666,18]})
({Houdini 2.0c x64: 3)} 42.Ng6+ hxg6 43. Re8+ Kh7 44. Rxa8 Bxd7 45. Rxa5 Bg4 46. Kf2 g5 47. hxg5 Kg6 48.
c5 Kf5 49. b4 g6 50. Ke3 Bh5 51. c6+ Ke6 52. b5 Kd6 53. Ra7 Bg4 54. c7 Kd7 55.
b6 Kc6 56. a5 Bc8 57. Kd4 Bf5 {[%eval 1123,18]})

Under hypothesis 1 (Ivanov is cheating) what happened? transmisstion problems? Wrong understanding of audio transmission?
Under hypothesis 2 (Ivanov not cheating) how it is possible? Not even a patzer like me would give such a pawn for nothing...

I would really appreciate your opinion. Thx.

Both 1 and 2

Ivanov was cheating earlier and when he got a winning position he stopped to cheat and decided to finish the game by himself.

Ivanov's playing strength is probably 1900-2000
In most cases 1900-2000 players are not going to lose that pawn but mistakes happen and if there are cases when GM's miss mate in 1 then there should be cases when 1900-2000 player blunders in that way.

[Uri Blass]

Living in a world of multiple proven cheating cases every exceptional tournament performance immediately is highlighted as suspect.

Regarding the above I like to add one more thought.

Collect cases of exceptional tournament performances (like the Ivanov case) before the days cheating with chess programs made sense. Back then they were accepted without criticism and if only one shows a similar behavior as in the Ivanov case then the accusation is baseless.

show me one similiar case of exceptional tournament performance(like the ivanov case) before 1990 when it did not happen in a single tournament but in many tournaments when the same player also did bad in other tournament

I know only about one case and it was a single tournament and not many tournaments like ivanov

Sofia polgar Rome

http://www.sofiapolgar.com/Rome.aspx?As ... eSupport=1

Of course I do not think that she was cheating but it was only a single event and Ivanov has some events when he score not logical result for his rating.

[noctiferus]

And here are the summaries ( fritzgui11, Houd20c, depth 18, 1 thread) of my check on two games played in "Old Capital", for what is worth: end of my homework .
Awaiting fo Don's results, with a more significant methodology!

Old Capital tournament (May 2013)
Ivanov (2303) first houd choice 26\second ch. 5\ third ch. or no match 4 (3 third choices)
Rombaldoni (2486) 17\ 7 \ 10
--------
Stanojoski (2399) first houd choice 9\ second ch. 8\ third ch. or no match 6
Ivanov (2303) 20\ 3\ 0