12. A non-transitory machine-readable medium having executable instructions to cause one or more processing units to perform a method comprising: retrieving a plurality of citations composed by a plurality of subjects citing a plurality of objects that fit one or more search criteria; determining an influence of each of the subjects and the objects using a citation graph, the citation graph including the plurality of citations each describing an opinion of an object by a subject, the citation graph including nodes or entities that are subjects that have an opinion or make citations, and objects cited by citations relative to subjects that have opinions or make citations; determining an expertise of a subject as a measure of the subjects expertise in a topic relative to a larger population of multiple subjects and allow for determination of expertise on any query term in real-time; ranking the cited objects of the plurality of citations using the influence and relative expertise of the subjects; and selecting objects as a search result for a user based on the matching of the objects with the search criteria as well as the relative expertise of the citing subjects.
12. A non-transitory machine-readable medium having executable instructions to cause one or more processing units to perform a method comprising: retrieving a plurality of citations composed by a plurality of subjects citing a plurality of objects that fit one or more search criteria; determining an influence of each of the subjects and the objects using a citation graph, the citation graph including the plurality of citations each describing an opinion of an object by a subject, the citation graph including nodes or entities that are subjects that have an opinion or make citations, and objects cited by citations relative to subjects that have opinions or make citations; determining an expertise of a subject as a measure of the subjects expertise in a topic relative to a larger population of multiple subjects and allow for determination of expertise on any query term in real-time; ranking the cited objects of the plurality of citations using the influence and relative expertise of the subjects; and selecting objects as a search result for a user based on the matching of the objects with the search criteria as well as the relative expertise of the citing subjects. 16. The non-transitory machine-readable medium of claim 12 , wherein the method further causes the processor to compute the relative expertise of a subject as a measure of the subject's expertise in a topic relative to a larger population of multiple sources and subjects.