Formally, where W(c) is the set of words (nouns) in the corpus whose senses are subsumed by concept c, and N is the total number of word (noun) tokens in the corpus that are also present in WordNet.
resnik's approach attempts to deal with the problem of varying link distances (see Section 2.5) by generally downplaying the role of network edges in the determination of the degree of semantic proximity: Edges are used solely for locating superordinates of a pair of concepts; in particular, the number of links does not figure in any of the formulas pertaining to the method; and numerical evidence comes from corpus statistics, which are associated with nodes.