From the term-document matrix you compute the term-term/correlation matrix which you normalize to obtain a new matrix (association clusters) that tells you how much are terms correlated with 1.0 as maximum value. But from this normalized correlation matrix, we can compute one last matrix called scalar clusters that shows the transitive correlation. In class it was shown that database, SQL, and index terms correlation numbers increased with the scalar clusters. When Gmail recommends people to add to an email to send, it's using some sort of correlation algorithm.
Ivan Zhou
