1. A method, comprising: providing a data store including documents; providing a semantic model including a plurality of concepts, wherein the semantic model is derived at least in part from a reference source that includes content not included in the data store; determining at least one similarity metric for each document of the plurality of documents, wherein each respective similarity metric represents a similarity between a respective document of the plurality of documents and a respective concept of the plurality of concepts in the semantic model; receiving a search query; computing at least one relevance metric of the search query, wherein each relevance metric represents a relevance of the search query to a respective concept of the plurality of concepts represented in the semantic model; and determining a ranking of at least a subset of the plurality of documents with respect to the search query using at least the at least one similarity metric and the at least one relevance metric.
1. A method, comprising: providing a data store including documents; providing a semantic model including a plurality of concepts, wherein the semantic model is derived at least in part from a reference source that includes content not included in the data store; determining at least one similarity metric for each document of the plurality of documents, wherein each respective similarity metric represents a similarity between a respective document of the plurality of documents and a respective concept of the plurality of concepts in the semantic model; receiving a search query; computing at least one relevance metric of the search query, wherein each relevance metric represents a relevance of the search query to a respective concept of the plurality of concepts represented in the semantic model; and determining a ranking of at least a subset of the plurality of documents with respect to the search query using at least the at least one similarity metric and the at least one relevance metric. 8. The method of claim 1 , wherein computing the at least one relevance metric includes embedding the search query in the semantic model.