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Bayesian networks come in equivalence classes

A set of conditional independencies can have many different Bayes nets that encode it. These together form a Markov equivalence class: i.e. a class of DAGs that share a skeleton (the undirected graph structure, \(\text{abs}(A)\) where \(A\) is the adjacency matrix) and colliders i.e. \(A \rightarrow B \leftarrow C\) where \(A\) and \(C\) are not adjacent.

In other words, you can't select a member of the class for free. The additional structure must have attached semantics of some kind.

Various regimes have been proposed. Lots of the thinking-about-agency wonkiness operationalizes to this or something bigger that contains this.

Further reading: