We use data on sequential water auctions to estimate demand when units are complements or substitutes. A sequential English auction model determines the estimating structural equations. When units are complements, one bidder wins all units by paying a high price for the first unit, thus...

To enhance our understanding of collusion in procurement settings, this paper quantitatively evaluates how the buyer's choice of a reserve price influences the sustainability of two previously devised collusive schemes. If the buyer does not select its reserve price strategically, then collusion...