This website has way more cheaters in the midle ELO ratings than advertised

It is very clear that this website is full of fake account, smurfs and cheaters. Particularly from ratings 1200-1900. In general, blatant cheating (or smurfing) seems to be caught quite fast, but occasional cheaters remain on the website for a long time. I've seen players with suspicious games from 2 years ago, who only recently got banned. What can we do to prevent this?? Can we put a reputation system in place?

Exactly how many did they advertise?

Ha ha.  Yeah, it's an issue.  They put a lot of resources into cheat detection, but other than that it's hard to think of another tool they could use that wouldn't be resource-intensive.  As it is, the best you can probably do is check the player's stats.  If they've played 1000 games, they're probably good.  If the account was opened last week?  Who knows.

Perhaps they could add that kind of filter to the opponent selection options.  Just as you can request the rating range that you're willing to play, add a tick box, "under 500 GP okay?" or something like that.

I don't think that helps much... I've seen players that have played a lot of games and still cheat occasionally. It's very hard to catch those that do that... Unfortunately the only solution I see is to play only with your friends...

Well, let me ask the obvious question:  how can you - YOU - tell if a person has cheated?

You can never tell for sure, unless when it is blatant (which does happen, since these people only cheat like that one game every many they are not banned - at least not soon enough). But the suspicion is the most annoying thing. When things like the following happens, I can't help but be suspicious:

- when a player has a losing position and then takes a minute and plays perfectly thereon, only to play like a noob again in time trouble...

- when a player plays some random sacrifice in the opening (which is a blunder) and after that plays perfectly (always with a pretty similar time per move)...

Anyway, the best would be to not be suspicious, and carry on. But playing these games simply defeats the purpose of playing games, since I don't learn anything from them (I can't make the moves that the computer tells I should have done to salvage the position in analyses later on)...

I hear you.  I hate the smurfs the most.  Some of them are really obvious - their first 25 games are all losses in less than 10 moves, which gets their rating established, and then they go into the arena tournaments to beat up on all the players rated 600 and below.  I just don't get where the fun in that would be for someone.

indeed... there are not even prizes in the tournaments... people just have an overwhelming need for false validation

This is only possible because the Arena format is complete nonsense. Pairing people based on rating and not on score is an insane idea, I just can't imagine how anyone ever thought that it is fine. Instead there should be swiss tournaments, and that's it, problem solved.

https://support.chess.com/article/648-what-do-i-need-to-know-about-fair-play-on-chess-com

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