CEAF precision and recall are both positively correlated with the score of this optimal alignment, which is computed by summing over each aligned entity pair the number of mentions that appear in both entities of that pair.
classifying mention pairs using such iterative approaches is undesirable for coreference resolution: since the non-coreferent mention pairs significantly outnumber their coreferent counterparts, the resulting classifiers generally have an increasing tendency to (mis)label a pair as non-coreferent as bootstrapping progresses (see Ng and Cardie (2003)).