Internet auctions on eBay and Yahoo allow sellers to list their auctions with a Buy-Now option. In such auctions the seller sets a buy price at which a bidder may purchase the item immediately and end the auction. In the eBay version of a buy-now auction, the buy-now option disappears as soon as...

This paper develops new econometric methods to estimate hospital quality and other models with discrete dependent variables and non-random selection. Mortality rates in patient discharge records are widely used to infer hospital quality. However, hospital admission is not random and some...