15. The computing device of claim 14 wherein the aggregated information includes aggregated revenue and converting visits.
14. A computing device for generating advertisement sets based on analysis of external referrals to a web site, comprising: at least one processor; and memory storing instructions that, when executed by the at least one processor, provide: a component that collects information from one or more referring sources that are external to the computing device and that refer visitors of the referring sources to the website, the information corresponding to referrals to the website by the referring sources, and each referral comprising referral information corresponding to a request for additional content that is sent responsive to user interaction with content of a corresponding referring source and that resulted in a visit to the website referred to by the corresponding referring source; a component that, for each of the referrals, identifies a referral type based at least in part upon a unique combination of a landing page type of the referral and one or more elements selected from a referring source identifier and a product identifier, the landing page type identifying a type of landing page that is displayed in response to user interaction with the referral; a component that aggregates the referral information for each referral type, the aggregated referral information including at least one of aggregated financial information and aggregated conversion information; a component that determines whether the aggregated referral information for a referral type satisfies an advertising criterion; a component that generates, based at least in part upon the aggregated referral information, an advertisement set for a referral type when its aggregated referral information satisfies an advertisement criterion, the advertisement set having an associated link including a query string corresponding to the referral type; and a component that submits the generated advertisement sets to an order placement service.