How does AtCoder rating map with CF rating?

How does AtCoder rating map with CF rating?

2 years ago, # | ← Rev. 2 →   +3 I'm 1500 there. But It's not good to scale I think because they have a different kind of rating system altogether. All I can say is that, it goes both ways with tourist being +600 there and me being -500.

• 16 months ago, # ^ | I think the reason behind this is that in Codeforces, if two competitors with a rating difference of compete in a single contest, it is expected that one competitor is time more likely to win the contest; and with a rating difference of , the ratio becomes ; with a rating difference of , the ratio becomes , and so on...... (it's actually not bad to think that the ratio between any master to tourist is no more than LOL), but in Atcoder the becomes , so lower-rated participants in Codeforces becomes even more lower-rated in Atcoder, while higher-rated participants in Codeforces becomes even more higher-rated in Atcoder......(the bound between is extremely high, namely QWQ); additionally, I personally think that Atcoder choses a rating calculation method more optimistic and tends to give more importance into "good times" contests of a participant, while Codeforces is more pessimistic and and tends to give more importance into "bad times" contests of a participant. Maybe there's consideration behind this ^_^.