Abstract. Many activities related to semantically annotated resources can be enabled by a notion of similarity among them. We propose a method for defining a family of semi-distances over the set of individuals in a knowledge base which can be used in these activities. In the line of works on distance-induction on clausal spaces, the family is parameterized on a committee of concepts. Hence, we also present a method based on the idea of simulated annealing to be used to optimize the choice of the best concept committee.