Moral graph
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A moral graph is a concept in graph theory, used to find the equivalent form undirected form of a directed acyclic graph. It is a key step of the junction tree algorithm, used in belief propagation on graphical models.
The moralized counterpart of a directed acyclic graph which is formed by connecting nodes that have a common child, and then making all edges in the graph undirected. The name stems from the fact the two node that have a common child are said to be married. Equivalently, a moral graph of a directed acyclic graph G is an undirected graph in which each node of the original G is now connected to its Markov blanket.
The correpsonding moral graph. The newly added arcs are shown in red in the moralized graph.
[edit] See also
[edit] References
- Cowell, Robert G.; Dawid, A. Philip; Lauritzen, Steffen L., Spiegelhalter, David J. (1999). "3.2.1 Moralization", Probabilistic Networks and Expert Systems. Springer-Verlag New York, p31-33. ISBN 0-387-98767-3.
- M. Studeny: On mathematical description of probabilistic conditional independence structures
