Over the past few days, links have come in through various means, and not all are chess-related. Buckle up!
Let’s start with a relative oldie, a nice summary of Ken Regan’s conclusions about Hans Niemann and how he came to them. (HT: Ervin Middleton)
Now here’s something more recent, which I came across on my own and which was sent to me by several sources. It’s a video by an FM named “Yosha” who uses ChessBase’s “Let’s Check” to claim that Niemann uniquely, and repeatedly, scored 100% by this test. Yosha also has a follow-up video, which Hikaru Nakamura discusses in a video of his own. Have there been any serious replies to Yosha? I saw one person refer to a single game of Arjun Erigaisi’s that also scored 100%, and the reply was that it was his opponent falling into a known opening trap.
Meanwhile, let’s take a break from chess scandals and see how things look elsewhere. Let’s start with…fishing. What could go wrong there? Oh, this. (HT: Carlos Campo) As a bonus, the Niemann situation is mentioned there, too. Thanks a bunch.
Well, at least there’s poker, because no one has cheated in cards, ever. Except maybe on this occasion.
There are more links of chess interest on the latest installment of Ben Johnson’s Linkfest, so if you remain insufficiently sated by the controversy that may be of use. And if I’ve missed some articles of interest, please help out in the comments section.
Also note what Chessbase themselves say about whether Let's check can be manipulated. It's only in the German manual, anyone able to read German (I know this is the case for Ken Regan) can check the original http://help.chessbase.com/CBase/14/Deu/index.html?grundlagen.htm - for others my partial translation:
"Because Let's Check is open for all engines, it is possible to use old, bad, or manipulated engines. Destructive things will happen, as always when people in some way contribute to a community on the Internet. ..... The system is self-correcting: unconfirmed variations will disappear over time and also outdated results from old engines will gradually vanish."
Here "old engines" probably means "old analysis", not analysis from old engines submitted recently for a "destructive" purpose. Some people suggest that this was done by FM Yosha Iglesias, or rather her anonymous source "gambit-man" - there seems to be no 100% correlation with modern engines. self-correction may happen but could take days, weeks or months.
Let's Check can be used for its stated purpose - better engine analysis than you manage yourself, your choice which engines from the cloud collection you prefer. It thus shouldn't be used for cheating detection, as it can be manipulated and the 100% verdict seems rather meaningless: one engine out of 20, 50 or 100 means 100% (not 5%, 2% or 1%), and several/many engines can cause a 100% verdict for any game.
Others apparently used the PGN-Spy software to find "evidence" against Niemann. The developer MGleason clearly states - both on GitHub here the program can be downloaded and later on Reddit - that this is "quick and dirty": at most reason for further investigations with more advanced methods, not evidence of guilt.
See (i.e., hear) GM David Smerdon discuss Let's Check at 1:20:00 on the recent Ben Johnson podcast at https://podcasts.apple.com/gb/podcast/perpetual-chess-podcast/id1185023674?i=1000580966031 This supplements what I've said about massive confirmation bias from counting a move at any time (by any one of multiple engines found in the cloud) as a match. If the utility is run backwards through a game while preserving hash, as the ChessBase/Fritz "Blundercheck" utility used to do, then you get upwards of 10 percentage points of bias from the resulting higher value of played moves in positions with clear advantage.
And see my appearance yesterday with Jim Eade on Sasha Starr's chess show for some updates: https://www.youtube.com/watch?v=KsxmmEg7_U4