Why online chess ratings are inflated/deflated

The correspondence pool is inflated as a whole and the bullet/blitz pool is deflated as a whole.

Does anyone have an answer to this?

Already answered. People losing rating points then being removed from the pool.

But why does the opposite happen in bullet/blitz?

People don't lose games just from not continuing to play on the site in bullet and blitz.

This is true. But still there is deflation. The average is more than 100 points lower in blitz than it should be ( 1099 instead of 1200 ). This means that high rated players leave the pool. Why is that?

Cheating.

Oops.

And more interesting to the rest of us.

BTW, the amount of time a player is able to spend on each move has nothing to do with the average within that pool.

I play online the same way as I do when I play live.
I rely only on myself.

I do take more time, because there is no limite.  But that is it! 

I do not use a database, nor a computer, nor videos for that game, etc.

I try to play online against people who play like me.

Sometimes I even mention to the other player if they are ok to use databases.  In that case I probably wouldn't play them.  I like people that beat me because they are thinking, not because they got to a position 15 moves deep just by copying other games!

Perhaps they also move to other places to play, where there are more strong players.

good point, a lot of players do time out

The pool of players and the number of games played are different. This is an explanation given as to why Chess960 ratings are lower than standard Online games by about 300 points. This site includes inactive players in it's stats which results in misleading averages.

I think most people play online like blitz. 

yes, but i think they are not as serious in their chess games.....

No matter how well or poor certain players perform, there will be the same number of wins as losses in the pool as a whole. Quality of individual play effects that individual's rating, but contributes nothing, zero, nada, to average rating vis-a-vis other pools.

It makes more sense to believe that correspondence ratings are higher because it attracts principally serious players.

My contribution is there might be a stark contrast between serious correspondence players and those who play correspondence like a 1|0 bullet game.  So the serious players' ratings are heavily inflated while less serious players actually have deflated ratings.  Just a theory.

2mooroo, your hypothesis is sound. For example, one of my current opponents is 500 below me in correspondence on this site, but is ~50 above me USCF. I'm fairly certain that I play CC with more seriousness, even though he is a better player.

Playing correspondence requires different skills than live. My favourite example is the No. 1. player of some facebook based correspondence site. His Fide rating is cca. 2200 which is a respectable rating though not sky high:

But at correspondence he has an incredible record:

He is beating players in correspondence who have much higher Fide rating than him and who take it seriously. His games are correspondence masterpieces.

To OP, even with 3-7 days some of us think in 1 min lol.  Not sure why eh.