Using exogenous sources for personalization of website services

Software running on servers at a website hosting a news service generates a first profile for a user of the news service. The first profile is based at least in part on implicit relevance feedback from the user on content presented by the news service. The software obtains a second profile for the user from a web-searching service. The software creates a score for a candidate item of content. The score is based on similarity of the candidate item to the first profile and similarity of the candidate item to the second profile. Similarity to the second profile measures at least similarity to a plurality of web-search queries and similarity to any titles of any search results resulting from each of the queries. The software then presents the item of content to the user in a content stream served by the news service, based on the score.