Abstract: ( ) ( ) ( ) 1. ( ) 2. (Bayesian network, Bayesnet, belief network) [1, 2, 3, 4, 5] [6, 7, 8, 9, 10] 0 1 1 0 Xi, Xj Xi → Xj Xj Xi X1 X2 X4 X3 X5 X2 0 1 X4 0 0.8 0.4 1 0.2 0.6 条件付確率表 P(X4|X2) P(X3|X1,X2) Pa(X3) Pa(X5) Pa(X4) P(X5|X3,X4) 1: Bayesian network Xj Pa(Xj) Xj Pa(Xj) ( Pa(Xj) ) P(Xj | Pa(Xj)) (1) n X1 · · · , Xn (2) P(X1, · · · , Xn) = n � j=1 P(Xj | Pa(Xj)). (2) 1 1 3 Pa(Xj) = x1