11. The method of claim 8 , wherein ordering the list of expert students according to the rank comprises: determining a first digital document read by a first expert student and a second digital document read by a second expert student; determining a first relevance of the first digital document relative to the digital document and a second relevance of the second digital document relative to the digital document; and ordering the list of expert students based on the first relevance of the first digital document and the second relevance of the second digital document.
8. A computer implemented method comprising: accessing a digital document, wherein the digital document relates to one or more topics; generating a list of expert students, wherein the expert students have authored one or more annotations relating to a topic similar to the one or more topics in the digital document; computing a confidence score for each annotation imported by a user accessing the digital document, wherein the confidence score is based on a test score of one or more users who imported the annotation, the test score being an indication of a quality of the annotation; computing a rank based on the confidence score for each annotation by the one or more users relating to the similar topic; and ordering the list of expert students according to the rank, wherein the rank identifies a level of expertise of the expert students; and presenting the ordered list of expert students, where the ordered list comprises a pre-defined number of expert students with a level of expertise meeting a predefined threshold.