1. A method for generating one or more functions for predicting a frequency with which an advertisement displayed in response to a query will be selected, the method comprising: receiving analytics data associated with a display of one or more advertisements in response to one or more queries; identifying one or more features associated with the one or more advertisements displayed in response to the one or more queries; and generating one or more functions for predicting a frequency with which a given advertisement displayed in response to a query will be selected using the analytics data and features associated with the one or more advertisements displayed in response to the one or more queries.