The statistics speak for themselves as both IDB and VDB are filed with DOT and are published for all to see.

Interestingly, B6 which says that it doesn't overbook, has one of the worst IDB rates in the business and for worse, IDB's 2/3rds of all denied boardings, suggesting that it's VDB offers are lowball.

An academic study is hard, because a lot of this would require drilling down a great deal further. Asking whether $200 is a little or a lot as VDB is the wrong question. The better question is whether it's a lot for a willingness to take bump off a non-stop and arrive 2 hours later than scheduled in roughly the same type of seat. It's also hardly surprising that there may not be a lot of takers for that offer on ORD-LGA at 7:00 AM (all business people) whereas midday Saturday, that might work just fine for a lot (leisure).

One thing does appear fairly certain, overbooking has become much more sophisticated and the carriers -- other than B6 apparently -- do a much better job of figuring out by how much they can overbook and still not oversell. But, even great software has its limits.