In this paper we study equilibrium- and experimental bidding behaviour in first-price and second price auctions with outside options. We find that bidders do respond to outside options and to variations of common knowledge about competitors' outside options. However, overbidding in first-price...

We introduce and experimentally test an auction model that allows for outside options of bidders as substitutes for the auctioned object under the private values assumption. Theoretically and in the experiments, bidders respond to their individual outside options and to variations of common...