26. The apparatus of claim 24 , wherein while determining the link-rating for a given link between a cluster and a terminal, the training mechanism is configured to: determine an expected count for the given link which indicates an expected number of times the given link was activated; calculate a significance for the given link by dividing a probability of the child given the parent by a probability of the parent, significance=p(child|parent)/p(child); and calculate the link-rating for the given link as a function of the significance and the expected count for the given link.
27. The apparatus of claim 26 , wherein the function for the link-rating is significance 2 ×expected count.