Patent ID: 8892685

Claim:
A computer-implemented method comprising: anonymously linking a plurality of identifiers, each identifier associated with a user and a specific requesting source, wherein anonymously linking includes linking at least two different identifiers that are associated with two different requesting sources used by the user to access content, and wherein anonymously linking includes linking the two different identifiers using an identifier that does not include any personally identifiable information; storing impression, click and interaction data for the user in association with respective identifiers; receiving a request for content from a user accessing content using a specific requesting source wherein the request includes a first identifier associated with the specific requesting source; identifying a plurality of candidate content items responsive to the request; determining a quality score for each candidate content item based at least in part on the stored impression, click and interaction data for the first identifier and one or more identifiers that are anonymously linked to the first identifier; selecting a content item from the plurality of candidate content items based at least in part on the determined quality scores; and providing the selected content item responsive to the request.