14. The system of claim 13 , wherein the instructions cause the one or more processors to perform operations comprising determining whether the training condition has been met based on a difference between a positive training score associated with one or more of the positive images and a negative training score associated with one or more of the negative images.
13. The system of claim 12 , wherein generating the image relevance model comprises iteratively adjusting the image relevance model for the particular query based on image feature values of the positive images and the negative images until a training condition has been met.