https://online-go.com/game/83661141
I am black, the content of the game has nothing special, but my opponent(white) is so strong. He had played like 1000+ games and remains 5k, but his strength should make him at least 3-4 dan in any other online go website. Any idea how has he got to stay at 5k(For me, I have only played a few games on the account)?
Hi and welcome to OGS!
Heh it seems like you are stronger than your opponent ^^
Also it looks like they have been around 1ā2k recently, but has lost some games which made them lose few ranks. OGSās rating system adjusts really quickly based on the game results, so i think both yours and your opponents ranks will keep adjusting when you play more games
Yep, after all I have only played like 20 games, so I am not 5k myself 
You may be amazed to find there are people with that many games who remain DDK.
How are you assessing his strength, other than by whom he wins and loses against?
In the games preceding your game with this person, they defeated weaker than 5k people, and lost to stronger than 5k people, with only one exception each way.
We do often hear āthis person is stronger than their rankā, but much less frequently see evidence for it.
(Note that Iām only 10k, so if the evidence is in the game play, I wonāt see it ā¦ and would love to hear about that).
The way people usually accomplish this is by throwing games against weaker players, much like this:
It seems that I was caught slacking off in class 
From the content of the game I can see it, and btw, I got something like 4 dan rank in FGS few years ago, and he seems even stronger then me that time.
And yet you beat him ā¦ so by your argument you are stronger than 4D ā¦ and yet you lose here to Dans. (3/3 games)
Iām sorrry that it sounds āpersonalā, which is unintented.
The point Iām making is that we do commonly hear informal strength assessments by users accusing others of sandbagging, and when probed those assessments are often like this one: donāt hold water.
Of course, maybe thereās more to emerge: you may point out aspects of play in your game with them where they were super strong - and then other Danās would be able to corroborate or refute.
But right now the only data on the table says āwhat a weird thread - a person who throws games accuses someone else, that they defeated, of being mysteriously strong, when all the data we have does not support thatā.
Welcome to a day in the life of sandbagging moderation 
Well, you are right, if I am indeed ACCUSING him of too strong, or winning someone disqualifies you from saying high of him, or I sandbagged him and foolishly post this to get myself condemned.
And btw, it seems that he has falled from 1700(1 kyu) at 1.22 to 5kyu in just a few days, however he is indeed too hardworking to play like 50+ games in a week, and I would consider this shift mild for him, and you may be right.
If that person is sandbagging - losing games on purpose to reduce their rank - then the right action is to report it using the report system, quoting the games suspiciously lost.
You can also report it saying āthey feel too strongā. The discussion above is what will unfold.
Sometimes people are right about this feeling.
Your title asked about āthe ogs grading systemā.
I think I answered that question: itās like any other grading system in the basics: if you beat someone, our assessment of your strength increases, and if you loose then its weaker.
A person stays the same rank if they loose to stronger people and defeat weaker ones.
I do agree that he is not sandbagging(or he would not need 50 games to fall). And this post is NOT a doubt about ogs elo system. Earlier this day I asked my ogs 5d friend and he told me that ogs do have one of the most solid ranking among all go servers, while he himself found out that even 10-15ks here usually play very rationally, which means they seldom collapse at a single edge. So I would like to end this discussion, leaving this post as a script for ogs solidness.
For some above saying me of tricking, you can have your opinion.
OGS has one of the most solid ranking among all go servers? Also why are you complaining about your win? Can you tell me who your OGS 5d friend isā¦ I have no idea where you are getting this information or maybe you just made it up
Maybe you meant solid as in strong ranks. Go servers ranks change from one to another. Recently there was a push to get OGS ranks as close to AGA/EGF ranks so maybe your AGA/EGF rank is around 4-5k.
Yes, yes, yes. You are bloodly right if everyone were as boring as you maybe to make something up for questioning and as considerate as you maybe to interpret my post as a complaint.
And if you wonder, the friend(acquaintance maybe, as we only know each other in another Go chatroom) I mentioned is åęŗęµ ,Mr. Curious.
Some people find it funny, Iāll never understand it. It must be a way to get attention.
I do not know from where can you guys read ACCUSATION.
If I had to debate with someone with such a poor reading comprehension, I would rather play deaf in this post from now on. And you are all free to have your opinions, while claiming that I am speechless to your WONDERFUL reasoning.
I wonder if this forum have an archive topic func after which you can comment but cannot reply. If there is I will do it.
You can ask that a mod close your thread.
