1. A computer-implemented method for optimizing displays in one or more user interfaces, the method comprising: retrieving a plurality of web entries from a database, each web entry of the plurality of web entries being a clickable item that is displayed on the one or more user interfaces; generating a first plurality of candidates comprising a first plurality of entries from the retrieved web entries; generating a second plurality of candidates comprising a second plurality of entries from the retrieved web entries; providing the first plurality of candidates for display on at least one of the one or more user interfaces, wherein the first plurality of candidates are displayed as a group; providing the second plurality of candidates for display on at least one of the one or more user interfaces, wherein the second plurality of candidates are displayed as a group; determining click-through rates for the first plurality of candidates; determining click-through rates for the second plurality of candidates; determining, from the plurality of candidates, a display pool of candidates to display based on the click-through rates of the first and second plurality of candidates; and updating the display pool of candidates responsive to retrieving additional web entries from the database.