## Is the maximum BDeu Bayesian Network always the empty network?

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For the BDeu score, it appears that the maximum possible score of BDeu for Bayesian Network structure learning is zero.

Does it mean that the best network is always the empty network?

The empty DAG (i.e. the DAG with no arcs) implies the factorization is simply $$P(X_1, \dots, X_n) = P(X_1) \dots P(X_n),$$ which is telling you all variables are independent.