Thats not for REP. That's to calculate how much power a user has (ability to give REP). It currently has nothing to do with Reputation. @wang might be the exception. Had to get some sleep but will look into it today.

Usually users with that much Vested shares into steem wouldn't have a Negative reputation.

Also from the small data set I have I've had users of 5 6 and 7 (all with enough Vested Share to atlas make a difference) up vote posts and the formula held try but I did not try negative numbers.

I also seem to have no effect on @wang when up voting him. Some defiantly research I will have to do today , unless someone from Steemit could share