조건부상호정보의 연쇄법칙 chain rule for conditional mutual information ¶
chain rule이 있음. curr goto 연쇄법칙,chain_rule#s-5
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We define the conditional mutual information of random variable X and Y given Z as:
 "$I(X;Y|Z)$")
-H(X|Y,Z) "$=H(X|Z)-H(X|Y,Z)$")
}\log\frac{p(X,Y|Z)}{p(X|Z)p(Y|Z)} "$=E_{p(x,y,z)}\log\frac{p(X,Y|Z)}{p(X|Z)p(Y|Z)}$")
Mutual information also satisfy a chain rule(연쇄법칙,chain_rule#s-5.2):
=\sum_{i=1}^{n}I(X_i;Y|X_{i-1},X_{i-2},\cdots,X_1) "$I(X_1,X_2,\cdots,X_n;Y)=\sum_{i=1}^{n}I(X_i;Y|X_{i-1},X_{i-2},\cdots,X_1)$")
}