Deciding Morality of Graphs is NP-complete

03/06/2013
by   Tom S. Verma, et al.
0

In order to find a causal explanation for data presented in the form of covariance and concentration matrices it is necessary to decide if the graph formed by such associations is a projection of a directed acyclic graph (dag). We show that the general problem of deciding whether such a dag exists is NP-complete.

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