Apparently he had a phone that he hid between his legs! I find it hard to believe too. I never played in a tournament with him.

Sorry to be a bit naive, and I know it is quite suspicious to have an earpiece taped to one's hand, but how was the person supposed to have cheated? Somehow the board position would also have to have been relayed in order for a presumable accomplice to pass back the suggested computer moves. I suppose he could have muttered the moves into a mic, but that seems improbable considering he was being filmed. And who would help a grown man cheat against a 9 yr old? Also, the fellow with the smartphone hidden between his legs - how was that supposed to have helped him? Phones need a lot of fiddling with and looking at to use a chess program... Certainly suspicious behavior in both situations, but airtight proof it isn't.

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Go? It's like sharing two bowls of cookies, but one person gets all of them.

Well for that reason it is clearly forbidden in FIDE rules to have a switched on electronic device on you inside the playing venue.
Therefore it does not need to be proved how ecactly they were using it to cheat, having it was already cheating.

Also: If you found physical evendence like this and then you look at the games and they provide statistical evidence as well, that makes for a whole lot better evidence than just the statistical one, not least because the problem is there are millions of player performances in tournaments. Even if nobody cheats, someone is bound to have a "one in a million" performance at some point, so that isnt so convincing evidence.
But would be a strange coincidence, if the one guy, that was caught using a phone is also the one guy with the "one in a million" performance if he wasnt cheating, would it?

I was recently wondering about the no phone rules now that LeelaZero can run on a phone. How does it work if players have family/dependants who want to be able to contact them? During tournaments I'm often chatting with my wife who gets lonely at home on her own. I'm quite happy to show the referee my phone that it's just chatting (and despite being called Sai she isn't helping me find the hand of God) and not a joseki dictionary or bot, but obviously if everyone does that it's quite a burden on the referee. Just last tournament she had a series of power cuts that set off the burglar alarm and not knowing the disarm code she plus the cat were going crazy for about 20 minutes before I answered.

Since the person is visually impaired, we can imagine the moves were communicated to him verbally. If he also had a hidden microphone, the information could be transmitted to an accomplice.

Other ways of cheating consist of using a second electronic device inside a shoe, and communicating to a smartphone via toe movements.



Maybe:

• Chat with your family before or after your game.
• In case of emergency, the family member can call the organizer of the tournament who will ask you if you want to call back later, or if you want to resign and call back immediately.

He was using a chess program on it.

Depending upon the emergency, it may not be necessary to resign, if the TD can monitor the call. Yes, that does allow the possibility of a one time cheat using coded messages.

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The Adkins Principle:
At some point, doesn't thinking have to go on?
— Winona Adkins
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Many are cold, but few are frozen.

Being married to a non-go-playing wife, I am totally sympathetic to the idea of connecting with family during a tournament.

That being said, it'd be pretty easy to cheat by chatting: simply construct a code to communicate moves. A simple example would be to use the letters A-T (skipping 'i' for kicks, like they do on KGS) for both the horizontal and vertical coordinates on the board. Then you could say that every time you say e.g., the word "a" in a chat message, the following word would start with a component of the coordinate.

For example, a standard opening might start with Q16, D4, Q4, D17. Converted to pure letter format, I guess this is QQ, DD, QD, DR.

So a sample chat dialog might be:

You: Hey, I have a quick question for you. Did I leave a quarter on my desk this morning? I don't seem to have all of the money I was supposed to bring for lunch.

Sai: Hmm. I see a dollar in here. I was going to go to the bank a day after tomorrow. I'll get more change then so we'll have extra change for next time.

You: Yesterday morning was a quiet one. I should have gone then. Yeah, let's go to the bank together in a day or two.

Sai: Ug. So bored here at home. Remember that time the power cut out? I really hope I don't need to use a disarm code this time. The cat went crazy pretty quick in a really short amount of time.

--

Anyway, you could make a more elaborate code, but the point is, you can communicate the moves back and forth in some way that only the two of you know about. And of course, even if Sai isn't the hand of god, there's nothing stopping her from invoking the hand of Leela at home with your cat.

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be immersed

There's at least one example in chess where a suspected cheater played a horrible move right next to what would have been a brilliant move. Presumably he misread the code or the wrong code was sent.

_________________
The Adkins Principle:
At some point, doesn't thinking have to go on?
— Winona Adkins
----
Many are cold, but few are frozen.

There was a time, not so long ago when, believe it or not there where no mobile phones. Somehow people managed to get through life just fine then and the truth is that they can manage just fine without them now.

[ Negative comment about another member's personal life removed. -JB, admin ]

I hope you can see the greater good in sacrificing your phone while you are playing. In case of emergency you can give your wife the number of some tournament official who can then alert you if there is some crisis.

As promissed earlier, here is analysis I made on middle game moves of Carlo Metta in four games - two internet games that preliminary analysis of deviations histogram showed that were very similar to Leela, and two of his live games from WAGC.


As you can see, internet games look very similar to each other, and live games look similar to each other, but there is great difference between online and live games. Lot of mistakes in live games, and basically no mistakes in internet games.


And here are more accompanying files - SGF game records, RSGF files with GRP Leela analysis, and there is Excel file with analysis of Metta's middle game moves - basically same thing as deviations histogram, but in more details.


As I have pointed out in paper, statistics can be deceiving, since it considers all moves are of same value.
I have analyzed here only middle game, as it is most "personal" part of the game, especially tenukis, and then sequences of moves between them.

In my opinion, thing is simple - if we have a player who is playing online like Leela, and playing much weaker in live games, then he was using Leela for online games.
No need for complicated statistics, or guessing why he plays much better online.

Thank you Milos, it seems a considered piece of eveidence to me. Perhaps it is not a fair request to ask you to do this, but I would be interested in 2 things.
1) Some way to show average deviation in the middlegame period you study - the diagrams are still a little difficult to read well, at least for me.
2) Very interested to see analysis of some games in PGETC season from League B. http://pandanet-igs.com/communities/eur ... ps/draw/57 . Maybe somebody is already doing this.

I remember beating Carlo in the PGETC#1, and now everyday I am eaten up by the question, why can't I beat Dragos

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North Lecale

1) In RSGF file deviations are given for every move, it is possible to extract them
2) Such analysis is very difficult. Even with this case where I think everything is clear, some might not be convinced totally.
And now imagine if someone used help from program only in critical fight? Almost impossible to prove.


It is impossible - you are not in the same league.

I think it's good that you're trying to avoid problems with earlier analysis, but the current execution seems lacking.

First of all, you clearly knew the result before you started. I'm not going to say that disqualifies your work, but if you make little to no effort to show weak points in your analysis, it makes it seem like you were simply following a trail that lead to the desired result. What you want to do is a blind study of many players, and you need to determine your method beforehand.

In particular, you need to compare what you did with other players - maybe the difference between tournament and online games is visible for others, too, even tho they did not cheat. Or it could be due to the time format, and that more thought is put into offline tournament games than online games (blitz or slow alike!). That possibility would invalidate your result and is easy to do, so it lessens the perceived quality of you work that it was omitted.

Also, if I did not miscount, all games together yield only about 30 or so data points (tenuki moves). That is not a lot, it can suffer from sheer coincidence. If you're only 99% certain (which is a lot from so few data), then that practically ensures that each year, several honest players would be 'convicted' of cheating. You need to have at least 5 or 6 nines. It's not simple.

Indeed, this is why I don't plan to look at Carlo's games, but other European players. It would be rather amusing if those who have been vehemently calling Carlo a Leela cheater ended up with stronger evidence that they themselves played more like Leela in the PGETC than in the WAGC or other offline events . Unfortunately only ~10 records per round at https://www.nihonkiin.or.jp/event/amaki ... cords.html, the year I went all players were asked to record their games and eventually a zip file with them all was available.

Two internet games I chose were suspicious because their histogram looked too much like Leela.
I made histograms for all games from this year's A league, btw. Several games stood out, and others are being examined.


Actually, I did most of it, as described above.


So you mean that if player uses Leela for 1-2 games, he cannot be punished, because of too little nodes?
And other, you are trying to go back to percentages discussion?
Weaker player can guess some moves of the stronger, but most... No chance.
I would like to see more of the Metta's live games (without any electronics on him, of course).
Let him try to play another game similar to Leela. Make him prove that he can.

Surely that's not so amusing. It would only be amusing if they, at the same time, also had unusually spectacular/ good tournament performance performance ratings.

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North Lecale

It would show that large variations in Leela similarity / mistake profiles or whatever measurement we are using for the same non-cheating person are actually rather common and so cannot be good evidence that they cheated when they did well.

First guy I checked is 2550 GoR, 2017/18 PGETC performance rating 2674, WAGC performance rating 2491. And no I don't suspect he cheated in PGETC at all (he benefited from being on low board so some easy wins, but also some good ones), and there are other real life tournaments with a better performance rating, something Carlo is indeed lacking. But this just shows a ~200 GoR difference in performance rating between 2 tournaments (with the better one online) is not so unusual/suspicious.

Fair enough; but how exactly did you calculate BD-G's tpr in each case? Is the number where entry rating essentially equals exit rating? If so are you iterating the calculation over all players?

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North Lecale

But you involuntarily used the statistics everywhere in your work, with the aggravating circumstance of having taken very few samples chosen a priori among those already more similar to Leela.

Are you familiar with the term cherry-picking?

https://en.wikipedia.org/wiki/Cherry_picking

You took the games most similar to Leela, among these games you took a dozen of moves among those more similar to Leela, and guess what? they are similar to Leela! utterly unexpected