9. The processor-implemented method of claim 1 , wherein user-specific linkage strengths are used to indicate a strength of association between pairs of linked subject items in the knowledge base and the linkage strengths are used in the determination of candidacy and in the computation of the priority values.
9. The processor-implemented method of claim 1 , wherein user-specific linkage strengths are used to indicate a strength of association between pairs of linked subject items in the knowledge base and the linkage strengths are used in the determination of candidacy and in the computation of the priority values. 11. The processor-implemented method of claim 9 , wherein the priority values are computed based on the understanding values of at least one of plurality of subject items, if the weighted average of the understanding values corresponding to the at least one of a plurality of advanced subject items is below an understanding value threshold, wherein the weights associated with the understanding values are a function of the user-specific linkage strengths between the at least one of the plurality of advanced subject items and the candidate subject item.