A survey some years ago on another online site, revealed the following: online ratings were higher than over-the-board federation ratings by 70 to 115 rating points, on average. While this does not imply that THIS site would have the same outcome, it might suggest that online ratings are generally higher than OTB ratings.
There are good reasons for this to be true, the principal one being that online players have more control over the choice of opponents than OTB players do, allowing some bias into the pairing process, and ultimately into the ratings.
Another possible difficulty in assessing the difference here is that the percentage of players here with OTB federation ratings might be lower than other sites. Still, it would be nice to put together a survey here to measure this very fact. (Of course, chess.com might be able to automate that if it chose to believe the numbers we put in on our profile pages.)
What multiplier would you use to determine the approximate USCF rating to this online rating. I would quess maybe .8 x online = aprox. USCF any ideas.