SELECTING ADVERTISEMENTS FOR PLACEMENT ON RELATED WEB PAGES

Systems and methods are described that select advertisements for placement on a series of consecutively-accessed web pages, such as consecutively-accessed web search results pages generated in response to a particular search. The systems and methods perform a separate advertisement ranking process to select advertisements for placement on each web page in the series of consecutively-accessed web pages at the time the web page is accessed. For web pages that follow the first web page in the series, the systems and methods utilize an advertisement ranking technique that calculates a probability that a user will select an advertisement based on certain user selection feedback features. The user selection feedback features for an advertisement are determined by comparing attributes of the advertisement to attributes of user-selectable items that were presented on one or more of the previously-accessed web pages in the series that are known to have been selected or not selected by the user.