Revenues and welfare in auctions with information release

This paper studies information release in symmetric, independent private value auctions with multiple objects and unit demand. We compare effects on welfare to those on the seller's revenue. Applying the dispersive order, the previous literature could only identify settings in which welfare provides the stronger incentives for information release. We generalize the dispersive order to k- and k-m-dispersion. These new criteria allow us to systematically characterize situations in which revenue provides stronger incentives than welfare, and vice versa. k-m-dispersion leads to a complete classification if signal spaces are finite and sufficiently many bidders take part.