Can Statistics Catch a Cheater at Chess?

Aside from the rise of chess-playing computers capable of beating human grandmasters in the late 1990s, the world of chess has largely stayed out of the news since the days of the Cold War in the 1970s. Until September 2022, that is, thanks to cheating allegations levied against Hans Niemann by the chess world's reigning grandmaster Magnus Carlsen.

Niemann lacks a clear track record when it comes to cheating at chess. He has acknowledged cheating using electronic devices while playing in online tournaments, including some as recently as in 2020, which has resulted in banning him from competing in these events. But the 19-year old Niemann denies having done so in so-called 'over the board' matches, where such cheating would be much more difficult for him to pull off.

That hasn't stopped some pretty wild speculation for how such cheating might take place. But that doesn't address the question of whether Niemann is cheating in these real-life matches.

That's where the maths of statistics comes into play. The following 11.5 minute video from Chess & Tech's Albert Silver summarizes what he learned from interviewing Kenneth Regan, a chess master who has successfully used statistics to identify players whose cheating was subsequently confirmed.

The TLDW (Too Long, Didn't Watch) summary is that Regan finds Niemann's level of play is consistent with his ranking, his outlier success in winning has largely come from his competitors making more mistakes than he has while playing against him.

Which is to say that if Niemann is benefitting from cheating in his analyzed over-the-board games, that cheating is very different in nature than what is being alleged most prominently in the media. The most likely scenario that would align with the statistical results is that Niemann's competitors are throwing their games when they play him. If that's true, given the number of players that would have to be involved, it will not be long before such a conspiracy would be found out.

And if so, what a story for the ages! We'd have to go back to 1919's Black Sox scandal or to 1994's ASU basketball point shaving scheme to find a near equivalent to that hypothetical sports crime. Given that the biggest cheating scandal to ever rock the chess world is known as "Toiletgate", it certainly would be a step up for the little noticed sport.