A novel experimental test of truthful bidding in second-price auctions with real objects

We present experimental evidence on bidding in second-price auctions with real objects. Our novel design, combining a second-price auction with an individual-specific binary choice task based on the outcome of the auction, allows us to directly identify over and under-bidding. We analyze bidding in real-object and induced-value auctions, and find significant deviations from truthful bidding in both. Overall, under-bidding is somewhat more prevalent than over-bidding; yet, the latter has a bigger magnitude, especially with induced values. At the individual level, we find no relation between the tendency to deviate from truthful bidding in induced-value vs. real-object auctions