English Chess Forum

JustinHorton wrote: ↑

Mon Jul 20, 2020 3:56 pm

Joseph Conlon wrote: ↑

Mon Jul 20, 2020 3:52 pm

if you define an inaccuracy as a move which is more than one 'pawn' worse than the best move (or whatever the definition is)

An estimation

Interesting. Am I to infer that if I were to drop a Q whilst playing K+Q+R v K then this would not even be classified as an inaccuracy as I would still be winning easily?

I watched a friend play a game on Lichess recently. It started 1.d4 Nf6 2. c4 g6?! (this being tagged as an inaccuracy). A Benoni position arose, W lost a piece to a pin down the e-file, swapped off into a losing ending and played on until mate. Both scored relatively lowly in terms of ACP loss despite my friend playing a “good” move that dropped the assessment from +61 to +24

Thus there would appear to be difficulties in using inaccuracy/mistake/blunder/ACP loss stats, particularly from one game, but over a 7 round tournament, I would have thought some correlation might become apparent.

I think one issue is this information is so new to us we are still unsure how to interpret it.

For example, I’m not sure what Mr Thomson is saying (with regard to engine matching). Also, we have probably not given much prior thought to how OTB cheating manifests itself on the board (as opposed to at the board or away from the board) so we are a little in the dark as to how to distinguish online between the rapid improver, the occasional cheater and the inveterate cheater.

Certainly good players make lots of errors (one reason they are not 2800). Are there “tells” exhibited by cheaters? For example, one might expect them to be suspiciously accurate in complex tactical positions but play odd moves in endings? Time taken might be a clue. What happens when two players using assistance meet?

Alistair Campbell wrote: ↑

Tue Jul 21, 2020 3:28 pm

For example, I’m not sure what Mr Thomson is saying (with regard to engine matching).

PGNSpy analysis is described here - https://github.com/MGleason1/PGN-Spy.

With only two "Undecided Positions" (defined as positions where the player's advantage is less than 2 pawns by default) in 3 games, and no losing positions at all, I think that means the player had a winning position within the first few moves. One of the other parameters is how many moves to ignore at the start of the game (default value 10) to try to avoid including known opening theory in the assessment of the player's standard of play.

Alistair Campbell wrote: ↑

Tue Jul 21, 2020 3:28 pm

JustinHorton wrote: ↑

Mon Jul 20, 2020 3:56 pm

Joseph Conlon wrote: ↑

Mon Jul 20, 2020 3:52 pm

if you define an inaccuracy as a move which is more than one 'pawn' worse than the best move (or whatever the definition is)

An estimation

Interesting. Am I to infer that if I were to drop a Q whilst playing K+Q+R v K then this would not even be classified as an inaccuracy as I would still be winning easily?

Very frequently dropping the piece might well (in my view) be the best move if bothering to save it were to delay mate by a move.

Are we clearly naming a junior again despite my suggestions?

Where?

Carl Hibbard wrote: ↑

Wed Jul 22, 2020 12:58 pm

Are we clearly naming a junior again despite my suggestions?

I believe the references are to tournaments run last weekend where the play of the 7/7 winner of the B section is being queried. The results of the tournament seem to have been suppressed.

Carl Hibbard wrote: ↑

Wed Jul 22, 2020 12:58 pm

Are we clearly naming a junior again despite my suggestions?

I don't think so. If someone thought they knew who was being referred to there's enough information to easily confirm or deny that. If someone had no idea who was being referred to it would take a lot of effort to determine who it was, and perhaps then only to a shortlist of possibilities.

Certainly I have no idea who this thread refers to, or whether the relevant tournament is in the UK or elsewhere in the world.

Roger de Coverly wrote: ↑

Wed Jul 22, 2020 1:16 pm

Carl Hibbard wrote: ↑

Wed Jul 22, 2020 12:58 pm

Are we clearly naming a junior again despite my suggestions?

I believe the references are to tournaments run last weekend where the play of the 7/7 winner of the B section is being queried. The results of the tournament seem to have been suppressed.

they are not, in any sense, suppressed

however you have clearly identified the player in question and effectively called them a cheat, which is very dangerous ground to be on if you are a publisher, and they are a minor, and they have passed the tests we have in place!

Once you eliminate the forced moves and the theory, the tests did not confirm any suspicious activity. One game was actually a walkover because the opponent was defaulted.

Ian Thompson wrote: ↑

Tue Jul 21, 2020 3:48 pm

Alistair Campbell wrote: ↑

Tue Jul 21, 2020 3:28 pm

For example, I’m not sure what Mr Thomson is saying (with regard to engine matching).

PGNSpy analysis is described here - https://github.com/MGleason1/PGN-Spy.

With only two "Undecided Positions" (defined as positions where the player's advantage is less than 2 pawns by default) in 3 games, and no losing positions at all, I think that means the player had a winning position within the first few moves. One of the other parameters is how many moves to ignore at the start of the game (default value 10) to try to avoid including known opening theory in the assessment of the player's standard of play.

Thanks. And profuse apologies for misspelling your surname

So basically not a lot of evidence to go on in this example.

Adam Raoof wrote: ↑

Wed Jul 22, 2020 1:32 pm

Once you eliminate the forced moves and the theory, the tests did not confirm any suspicious activity. One game was actually a walkover because the opponent was defaulted.

Weird - I was actually watching that game LIVE, and I have a PGN of it. So how come the opponent "defaulted"? In fact, I was watching all the games that opponent "defaulted" as he was as suspicious to me as PlayerB.

He failed the test.