We partnered with a large online auction website to test differing messages' effects on the decision to donate to charity at checkout. Our setting, where impulsive decisions are likely to be driving donations, allows us to evaluate intuitive responses to messages prompting a donation. We find...

Economic theory suggests that decentralized markets can achieve efficient outcomes if buyers and sellers have many opportunities to trade. We examine this idea empirically by developing a tractable dynamic model of bidding in an overlapping, sequential auction environment and estimating the...

The transition of the advertising market from traditional media to the internet has induced a proliferation of marketing agencies specialized in bidding in the auctions that are used to sell ad space on the web. We analyze how collusive bidding can emerge from bid delegation to a common...

Quality certification programs help consumers to identify high-quality products or sellers in markets with information asymmetries. Using data from eBay UK's online marketplace, we study how certification's impact on consumer demand varies with market- and seller-level attributes, exploiting...

Can sellers credibly signal their private information to reduce frictions in negotiations? Guided by a simple cheap-talk model, we posit that impatient sellers use round numbers to signal their willingness to cut prices in order to sell faster, and test its implications using millions of online...

Reputation is critical to foster trust in online marketplaces, yet leaving feedback is a public good that can be under-provided unless buyers are rewarded for it. Signaling theory implies that only high quality sellers would reward buyers for truthful feedback. We explore this scope for...

A growing body of empirical literature finds that consumers are relatively limited in how much they search over product characteristics. We assemble a dataset of search and purchase behavior from eBay to quantify the returns, and thus implied costs, to consumer search on the internet. The...

We study reserve prices computed to maximize the expected profit of the seller based on historical observations of incomplete bid data typically available to the auction designer in online auctions for advertising or e-commerce. This direct approach to computing reserve prices circumvents the...

We study patterns of behavior in bilateral bargaining situations using a rich, new dataset describing over 88 million listings from eBay's Best Offer platform, with back-and-forth bargaining occurring in over 25 million of these listings. We document patterns of behavior and relate them to...

The economic literature on online auctions is rapidly growing because of the enormous amount of freely available field data. Moreover, numerous innovations in auction-design features on platforms such as eBay have created excellent research opportunities. In this article, we survey the...