Is Ivanov a cheater?

This 'evidence' doesn't make sense to me, never has. In my experience, engines constantly change their top move, every time they cycle through to a new depth level. There is no 'top move'. I suspect a lot of people get falsely accused of cheating, because the accuser simply sits and waits for the move to become the 'top move', and then they say, "Aha!" However, if they'd wait another thirty seconds, a different move would then be temporarily at the top of the list.

But if the tournament games were live (I meant the competitors were sitting on the table and played with wooden board), how could Ivanov cheat with the engines? It would have required a laptop at least...?

Hey Adam, that is simply not the case, they do not find a different top move each time, after 10 seconds it has already stabelized, off course in certain positions, you have to wait longer, and yes it can switch between a few(generally 2) moves from time to time, and it certain position he finds a bunch 2 or more equal lines (when it was equal I counted it as top move, but this happened very rarely)

By the way I found a post of someone else who did some extensive research with stockfish. Here are his findings:

I have again gone through all nine games with Stockfish on my laptop. Ivanov makes a total of 290 moves (I did not evaluate the opening moves that could be considered to be theory). 256 of these are the first choice of Stockfish. That makes 88%. It would have been higher if he hadn´t started to lose his magic in round 8 after the 15 first moves. In the last 19 moves he commits several mistakes, small and big. It is reported that the internet relay of the games went down during this round.

So how good is 88%? I took nine top games of nine world champions to compare with. Here is a summary of the results.

Lasker - Capablanca, St Petersburg 1914, 1-0. Lasker reaches 81%.

Nimzowitsch - Capablanca, St Petersburg 1914, 0-1. Capa reaches a record 84%.

Botvinnik - Keres, Moscow 1953, 1-0. Botvinnik makes 79%.

Fischer - Spassky, Reykjavik 1972, game 6, 1-0. Fischer makes 61%. Considered to be Fischers best effort in the match by many including Spassky - who applauded Fischer on stage after the game.

Karpov - Kasparov, Wch match 1993, game 17, 1-0. Karpov reaches 64%.

Karpov - Kasparov, Linares 1993, 0-1. Kasparov makes 76%.

Topalov - Anand, Wch match 2010, final game, 0-1. Anand makes 76%.

Carlsen - Anand, Master final 2012, 1-0. Carlsen makes 57% in this brilliant game.

Kramnik - McShane, London CC 2012, 1-0. Kramnik makes 68%.

A total of 249 moves when the known opening moves are subtracted. 181 are first choice moves for Stockfish. That makes 73%.

Ivanov is not playing world champion chess. He plays 15% better.

So how unlikely is it to play that well by pure chance? Let´s do some math.

If we simplify and say that in every position there is only two moves a good player (or computer) has to choose from. An oversimplification for sure, but the results are staggering. Then the chance to reach the world champions score 73% is in the order of one in 10 to the power of 21 (a one with 21 zeroes after it). To reach Ivanovs 88% you have one chance in 10 to the power of 53.

If we grant Ivanov world champion strength his chance of reaching 88% would be one in 10 to the power of 32.

You don't get a ridiculous engine match rate like doktor_nee said if someone is letting you win.

Right, Scottrf. I should read more than the first post before I comment. It's outta there!

Maybe Ivanov was really studying during his hiatus. It once happened to the great Akiba Rubinstiens career. Returning to chess in brilliant form. Rogelio Antonio too had his chess career on the downside when younger ones came in. But later he gained back momentum winning /getting place positions in various tournaments. Ive read that Ivanchuk onced suffered from breakdown/fatigue and almost retired from chess but at the present is still playing well. I think ivanov deserves his winnings.

It also happened to Spassky. He was a positional, scientific player. THen Spassky took a hiatus and came back as the tactical, attacking player that he's known as.

Exactly, so the idea that you would have a 100% match between a player's moves and the engine is really nonsensical. It simply can't happen. After ten seconds you might think the move stabilizes, but give it a couple more minutes -- its gonna change to something else. You are just deluding yourself into seeing a pattern that isn't there.

So chess engines can't be trusted, as they are always changing their moves... You really have no clue pal. Why don't you check it yourself and see.

I'm really tired of all these people who don't check for themselves, but are very willing to challenge that what they don't know about.

That's exactly why top3 is more valuable in online cheat detection than single top engine move.

I didn't say chess engines can't be trusted. I'm saying that you can't say someone is cheating just because you found that the computer suggested the same moves. I use Houdini every day, and it definitely changes its mind quite regularly. It doesn't have a "top move" which you can compare to someone's moves.

Well that was also only 1 game where it happened to agree 100% with the moves I saw as top lines.

In the other games there were also a few second and third options he made, which were never more than 0.10 difference in evaluation. Anyways, the case here is if Ivanov is a cheater.

If you look at the games with an engine you will see he is. 

Fo some moves to become top move, you will wait forever, and it wont happen. If every move becomes top move at some stage, it is highly suspicious, and could probably be seen as proof of cheating.

I don't know about Ivanov, but Bindrich was definitely cheating.

Well, there is a difference between skepticism and denialism or between silliness and honesty.

It surprises me anyone can seriously think this little nothing but cheater and thief deserves his victories - it was prize tournament, so it should be called fraud or theft.

No, the performance itself doesn't constitute proof of guilt.

However the coincidence with engine does. And unfortunately, the lack of physical evidence can't refute it.

I ran Ivanov's 9 games through batchanalyzer, letting it determine which were the book moves not to be analyzed (usually I check with MegaBase and a CC database for this, but it's more work than I want to do for this one).

Settings were 12-22 ply depth/45 seconds, hash 256mb

Engine Houdini 103a

Core2Duo 2.00 GH

{ Borislav Ivanov (Games: 9) }
{ Top 1 Match: 223/314 ( 71.0% )  Opponents: 152/313 ( 48.6% )
{ Top 2 Match: 260/314 ( 82.8% )  Opponents: 206/313 ( 65.8% )
{ Top 3 Match: 286/314 ( 91.1% )  Opponents: 246/313 ( 78.6% )
{ Top 4 Match: 294/314 ( 93.6% )  Opponents: 270/313 ( 86.3% )

As I understand the ChessBase article, round 8 had no live feed, a game which he lost. The following is his round 8 analysis.

{ White: Borislav Ivanov }
{ Top 1 Match: 14/27 ( 51.9% )
{ Top 2 Match: 19/27 ( 70.4% )
{ Top 3 Match: 21/27 ( 77.8% )
{ Top 4 Match: 23/27 ( 85.2% )

His numbers for this round were far below his average for all the others.

Subtracting round 8 from the overall results:

{ Top 1 Match: 209/287 ( 72.8% ) 
{ Top 2 Match: 241/287 ( 84.0% )
{ Top 3 Match: 265/287 ( 92.3% ) 
{ Top 4 Match: 271/287 ( 94.4% ) 

These are terrible numbers, just terrible. A top GM like Carlsen or Anand only can muster c. 60/75/85%.

Am I right in thinking that those numbers are strong evidence of blatant cheating?

God yes. The guy and his accomplices got the exploding dye pack all over their hands and faces on this heist.

Maybe he was popping adderall or developing some sort of brain tumor that has given him amazing chess skills.

Perhaps, working late in the laboratory, he was bitten by a radioactive, chess-playing spider.