【ML】Probabilistic Graphical Mode

Probabilistic Graphical Model (PGM, or Graphical Model) is a probabilistic model for which a graph expresses the conditional dependence structure between random variables. Two branches of graphical representations of distributions are commonly used, namely, Bayesian networks and Markov random fields.

Bayesian network is a probabilistic graphical model that represents a set of variables and their conditional dependencies via a directed acyclic graph.

Bayesian Network Syntax

The graph: G = {V, E}    

A set of local conditional distributions: P = {}

Bayesian Network Semantics

A Bayesian Network N with nodes defined a joint distribution