We present an empirical investigation of the role of marketing agencies in Google's online ad auctions. By combining data on advertisers' affiliation to marketing agencies with data on bidding in ad auctions, we analyze how changes in the concentration of clients in the same industry under the...

For some kinds of goods, rarity itself is valued. "Fashionable'" goods are demanded in part because they are unique. In this paper, we explore the economics of rare goods using auctions of limited-edition shoes held by an e-commerce platform. We model endogenous entry and bidding in multi-unit...

In eBay s Buy-it-Now auctions sellers can post prices at which buyers can purchase a good prior to an auction. We study how sellers set Buy-it-Now prices when buyers have independent private values for a single object for sale. We test the predictions of a model by combining the real auction...

In Buy-It-Now (BIN, hereafter) auctions, sellers can make a "take-it-or-leave-it" price offer (BIN price) prior to an auction. We analyse experimentally how eBay sellers set BIN prices and whether they benefit from offering them. Using the real eBay environment in the laboratory, we find that...

I model the environment of Internet auction sites, such as eBay, as sequential ascending auctions. New buyers may enter the auction site after some of the auctions have completed and only bid for the remaining auctions. I characterize a perfect Bayesian equilibrium in the dynamic game. Because...

We investigate experimentally on eBay how sellers set prices in "Buy-It-Now" (BIN) auctions. We find that the eBay format leads to prices substantially below those expected in second-price auctions. Moreover, our results reveal that the information available on eBay about buyer experience and...

The paper derives a theoretical model, along with a piece of empirical evidence, of the determination of prices at which a seller sells objects in the "Facebook Group Marketplace" using an adaptive price mechanism and a sequential reverse auction model. This is an informal marketplace and has...

A great deal of late bidding has been observed on internet auctions such as eBay, which employ a second price auction with a fixed deadline. Much less late bidding has been observed on internet auctions such as those run by Amazon, which employ similar auction rules, but use an ending rule that...

In second price internet auctions with a fixed end time, such as those on eBay, many bidders snipe , i.e., they submit their bids in the closing minutes or seconds of an auction. Late bids of this sort are much less frequent in auctions that are automatically extended if a bid is submitted very...

Because of discrete bid increments, bidders at electronic auctions engage in shading instead of revealing their valuations, which would occur under the commonly assumed second-price rule. We demonstrate that misspecifying the pricing rule can lead to biased estimates of the latent valuation...