We present an equilibrium search model that parsimoniously rationalizes the use of auctions as a sales mechanism for new-in-box goods--a frequent occurrence in online retail markets--and analyze whether the existence of these auctions is welfare enhancing relative to a market consisting only of...

Using a large set of private health insurance claims, we estimate how physicians’ financial incentives affect their treatment choices in heart attack management. Different insurance plans pay physicians different amounts for the same services, generating the required variation in financial...