  This article studies the problem of assessing relevance to each of the rules
of a reference resolution system. The reference solver described here stems
from a formal model of reference and is integrated in a reference processing
workbench. Evaluation of the reference resolution is essential, as it enables
differential evaluation of individual rules. Numerical values of these measures
are given, and discussed, for simple selection rules and other processing
rules; such measures are then studied for numerical parameters.
