Deciding Morality of Graphs is NP-complete
arXiv:1303.1501
Abstract
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.
Appears in Proceedings of the Ninth Conference on Uncertainty in Artificial Intelligence (UAI1993)