1. A method performed by one or more computers, the method comprising: receiving a first search query from a user device, wherein the first search query has been determined to relate to a first entity of a first entity type, and wherein a plurality of second entities of a second entity type have a predetermined relationship with the first entity; determining a respective ranking score for each second entity of the plurality of second entities of the second entity type, the determining comprising: determining a frequency of occurrence of authoritative resources for the second entity of the second entity type in search results for previously submitted search queries, each authoritative resource for the second entity being a resource whose occurrence in the search results for the previously submitted search queries has been determined to be an indicator that the received search query is directed to the second entity; and determining the respective ranking score for the second entity based at least in part on the frequency; ordering the second entities of the second entity type according to the ranking scores; receiving search results for the first search query provided by a search engine, wherein each of the search results identifies a respective resource; and transmitting the search results and information identifying each of the plurality of second entities of the second entity type to the user device as part of a response to the first search query, wherein, when presented on the user device, the information identifies each of the plurality of second entities in an order that matches the ordering.
1. A method performed by one or more computers, the method comprising: receiving a first search query from a user device, wherein the first search query has been determined to relate to a first entity of a first entity type, and wherein a plurality of second entities of a second entity type have a predetermined relationship with the first entity; determining a respective ranking score for each second entity of the plurality of second entities of the second entity type, the determining comprising: determining a frequency of occurrence of authoritative resources for the second entity of the second entity type in search results for previously submitted search queries, each authoritative resource for the second entity being a resource whose occurrence in the search results for the previously submitted search queries has been determined to be an indicator that the received search query is directed to the second entity; and determining the respective ranking score for the second entity based at least in part on the frequency; ordering the second entities of the second entity type according to the ranking scores; receiving search results for the first search query provided by a search engine, wherein each of the search results identifies a respective resource; and transmitting the search results and information identifying each of the plurality of second entities of the second entity type to the user device as part of a response to the first search query, wherein, when presented on the user device, the information identifies each of the plurality of second entities in an order that matches the ordering. 3. The method of claim 1 , wherein the ranking score for a particular second entity of the second entity type is further based at least in part on how frequently the particular second entity is searched for by users after submitting a search query directed to the first entity.