1. A method comprising: generating, by the computer system, initial scores for one or more terms and a plurality of images based on content that is associated with the plurality of images, wherein the initial scores indicate how closely the one or more terms are associated with the plurality of images in the content; determining probabilities of navigating between images in the plurality of images, wherein the probabilities of navigating between images indicate how likely a user, who has viewed an image, is to perform an action that will cause another image to be displayed to the user; determining, by the computer system, scores for the plurality of images and the one or more terms based on i) the probabilities of navigating between images and ii) the initial scores; identifying a particular image from the plurality of images to associate with a particular term from the one or more terms based on the scores, wherein the content did not indicate an initial association between the particular image and the particular term based on a portion of the content that is associated with the particular image not including the particular term; and providing, by the computer system, information that identifies the particular image and the particular term.