Returning factual answers in response to queries

摘要

Methods, systems, and apparatus, including computer programs encoded on a computer storage medium, for information retrieval. In one aspect, a method includes receiving a fact query; determining an expected type of answer to the fact query; identifying search results responsive to the fact query; identifying phrases from the resources corresponding to the search results that correspond to a form of the expected type; determining a score for each of the identified phrases; and presenting an answer to the fact query using the scores.