While most models of auctions and competitive bidding assume that each bidder's utility for an outcome depends only on his own profit, we allow the utility to also depend on any regret that a bidder suffers after the fact and characterize when and how this affects bidding. Specifically, a winner...

We investigate the effect of regret-related feedback information on bidding behavior in sealed-bid first-price auctions. Two types of regret are possible in this auction format. A winner of the auction may regret paying too much relative to the second highest bid, and a loser may regret missing...