36. The non-transitory computer storage medium of claim 27 , wherein the operations further comprise: receiving input from a second user indicating that one or more of the first documents are preferred documents; calculating a respective document weight for each of the preferred documents; nd wherein calculating the aggregate strength of relationship score for each candidate document includes weighting the strength of relationship scores for the candidate document and each of the preferred documents by the respective document weight for the preferred document.
36. The non-transitory computer storage medium of claim 27 , wherein the operations further comprise: receiving input from a second user indicating that one or more of the first documents are preferred documents; calculating a respective document weight for each of the preferred documents; nd wherein calculating the aggregate strength of relationship score for each candidate document includes weighting the strength of relationship scores for the candidate document and each of the preferred documents by the respective document weight for the preferred document. 37. The non-transitory computer storage medium of claim 36 , wherein the operations further comprise: receiving input from the second user indicating that one or more of the first documents are disliked documents; calculating a respective document weight for each of the disliked documents; and wherein calculating the aggregate strength of relationship score for each candidate document includes weighting the strength of relationship scores for the candidate document and each of the disliked documents by the respective document weight for the disliked document.