Hermes: an Efficient Algorithm for Building Galois Sub-hierarchies
نویسندگان
چکیده
Given a relation R ⊆ O × A on a set O of objects and a set A of attributes, the Galois sub-hierarchy (also called AOC-poset) is the partial order on the introducers of objects and attributes in the corresponding concept lattice. We present a new efficient algorithm for building a Galois sub-hierarchy which runs in O(min{nm, nα}), where n is the number of objects or attributes, m is the size of the relation, and nα is the time required to perform matrix multiplication (currently α = 2.376).
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