Fig. 2.

Illustration. a Path diagram $\mathcal{G}$ for SEM with configuration in (4). b Moral subgraph ${\mathcal{G}}_{\{X_1,X_2,X_3\}}^m$ induced by an(X₁,X₂,X₃)={X₁,X₂,X₃}. c Moral graph ${\mathcal{G}}^m$