[Kasparov vs the World][1] was a chess game where Gary Kasparov played against many people on the internet. Gary won. **I am basically wondering if 1-vs-many chess games have been done systematically, and if there are some statistical results from this?** e.g.:

* Practically speaking, if we have N players of Elo rating X each, what is the Elo rating of the combined team (typically)?

* Practically speaking, if we have N players of Elo rating ranging between X - 500 and X + 500, what is the Elo rating of the combined team, typically?

The Kasparov vs the world match suggests to me that Elo (team) is approximately equal to Elo (best player in team) + a small number, but I'd like to know if there are statistics. 

Also, there are some limitations to what the Kasparov vs The World match tells us:   
 1. Gary apparently watched the forum in which his opponents communicated, which wasn't clearly forbidden beforehand.
 2. it's not clear to me how serious the opponents took the game, as it was maybe a bit informal.
 3. It's only one game.


  [1]: https://en.wikipedia.org/wiki/Kasparov_versus_the_World