Score contribution per author:
α: calibrated so average coauthorship-adjusted count equals average raw count
Winners in online auctions frequently fail to complete purchases. Major auction platforms therefore allow “second‐chance” offers (the runner‐up bidder pays his own bid price) and let sellers leave negative feedback on buyers who default. We show theoretically that (i) all else equal, the availability of second‐chance offers reduces bids; (ii) sellers have no incentive to exclude bidders, even if they are nearly certain to default; (iii) buyer reputation systems reward bidders known to default with a positive probability. Our experiments show that the economic forces identified in the theoretical model are important enough to have predictive power for bidder behavior.