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| === Bayes' rule 贝叶斯法则 === | | === Bayes' rule 贝叶斯法则 === |
| [[Bayes' rule]] for conditional entropy states | | [[Bayes' rule]] for conditional entropy states |
| + | 条件熵状态的贝叶斯法则 |
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| :<math>H(Y|X) \,=\, H(X|Y) - H(X) + H(Y).</math> | | :<math>H(Y|X) \,=\, H(X|Y) - H(X) + H(Y).</math> |
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| ''Proof.'' <math>H(Y|X) = H(X,Y) - H(X)</math> and <math>H(X|Y) = H(Y,X) - H(Y)</math>. Symmetry entails <math>H(X,Y) = H(Y,X)</math>. Subtracting the two equations implies Bayes' rule. | | ''Proof.'' <math>H(Y|X) = H(X,Y) - H(X)</math> and <math>H(X|Y) = H(Y,X) - H(Y)</math>. Symmetry entails <math>H(X,Y) = H(Y,X)</math>. Subtracting the two equations implies Bayes' rule. |
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| + | 证明,<math>H(Y|X) = H(X,Y) - H(X)</math> 和 <math>H(X|Y) = H(Y,X) - H(Y)</math>。对称性要求<math>H(X,Y) = H(Y,X)</math>。将两个方程式相减就意味着贝叶斯定律。 |
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| If <math>Y</math> is [[Conditional independence|conditionally independent]] of <math>Z</math> given <math>X</math> we have: | | If <math>Y</math> is [[Conditional independence|conditionally independent]] of <math>Z</math> given <math>X</math> we have: |
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− | :<math>H(Y|X,Z) \,=\, H(Y|X).</math>
| + | 如果给定<math>X</math>,<math>Y</math>有条件地独立于<math>Z</math>,则我们有: |
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| + | :<math>H(Y|X,Z) \,=\, H(Y|X).</math> |
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| === Other properties 其他性质 === | | === Other properties 其他性质 === |