Combinatorial Auctions
	n Auctioneer sells a set of non-homogeneous items n Bidders often have complex valuations n complementarities • e.g. V(TV & VCR) > V(TV) + V(VCR) n substitutabilities • V(TV1 & TV2) < V(TV1) + V(TV2) n Solution: allow bids on bundles of goods n achieves a higher revenue and social welfare than separate auctions n Two hard problems: n Expressing valuations n Determining optimal allocation