Funds from this grant support the work of Stanford economists Jonathan Levin and Liran Einay, who have obtained unprecedented access to a massive dataset on consumer behavior data collected by the internet retailing giant and auction site eBay. The eBay data is a goldmine of information containing records of hundreds of millions of transactions over ten years, including the histories of every seller, details on every item ever listed on the site, and records of every click made by site users. Grant monies will support Levin and Einay's work analyzing this data, which will initially focus on three distinct issues: how buyer and seller behavior have changed over time particularly with regard to auctions; how to model seller learning; and the impact of changes in online sales taxes on buyer and seller behavior. The depth and richness of the dataset they will be analyzing promises to shed new light on our understanding of what happens when people go shopping.