Finding Minimal D separators
نویسندگان
چکیده
We address the problem of nding a minimal separator in a di rected acyclic graph DAG namely nding a set Z of nodes that d separates a given pair of nodes such that no proper subset of Z d separates that pair We analyze several versions of this problem and o er polynomial algorithms for each These include nding a minimal separator from a restricted set of nodes nding a minimum cost separator and testing whether a given separator is minimal We con rm the intuition that any separator which cannot be reduced by a single node must be minimal TECHNICAL REPORT R-254 February 1998
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