Bayesian networks A simple,graphical notation for conditional independence assertions and hence for compact specification of full joint distributions ·Syntax: -a set of nodes,one per variable a directed,acyclic graph(link~"directly influences") a conditional distribution for each node given its parents: P(X|Parents(Xi)) In the simplest case,conditional distribution represented as a conditional probability table (CPT)giving the distribution over X;for each combination of parent values Bayesian networks • A simple, graphical notation for conditional independence assertions and hence for compact specification of full joint distributions • Syntax: – a set of nodes, one per variable – – a directed, acyclic graph (link ≈ "directly influences") – a conditional distribution for each node given its parents: P (Xi | Parents (Xi )) • In the simplest case, conditional distribution represented as a conditional probability table (CPT) giving the distribution over Xi for each combination of parent values