Computing Minimal Mappings between Lightweight Ontologies.

As a valid solution to the semantic heterogeneity problem, many matching solutions have been proposed. Given two lightweight ontologies, we compute the minimal mapping, namely the subset of all possible correspondences, that we call mapping elements, between them such that (i) all the others can be computed from them in time linear in the size of the input ontologies and (ii) none of them can be dropped without losing property (i). We provide a formal definition of minimal mappings and define a time efficient computation algorithm which minimizes the number of comparisons between the nodes of the two input ontologies. The experimental results show a substantial improvement both in the computation time and in the number of mapping elements which need to be handled, for instance for validation, navigation, and search.