We study the effects of allocative and informational externalities in (multi-object) auctions and related mechanisms …. Such externalities naturally arise in models that embed auctions in larger economic contexts. In particular, they appear … driving force behind many new, specific phenomena with allocative externalities: even in complete information settings …

informational externalities (PIE). This assumption implies upward drifting price sequences at sequential auctions, which is … environment, in which the bidders' values can exhibit both PIE and NIE (negative informational externalities). The case of NIE can …

, private information, and identity-dependent externalities. We derive the seller's optimal mechanism and characterize its main … commonly used in practice is an optimal mechanism if externalities are sufficiently large …

-cost bidding. This is less likely when externalities are not internalised. For markets where bids are competitively priced, this … paper provides evidence to suggest that methods to minimise externalities associated with renewables deployment should be …