Abstract:A mean filed interval propagation algorithm is designed based on incomplete functional iterations. This algorithm can yield the expectation bound of variables. Firstly, a concept of computation tree is proposed to reveal the iteration computation process of Ising mean field. Then, a mean field interval propagation algorithm based on the Ising computation tree is put forward, which propagates message intervals through the computation tree and presents the mean intervals of random variables in root node. It is proved that the variable mean interval computed by the interval propagation algorithm with 2-layer computation tree contains the exact value, called the mean bound of random variable. Finally, theoretical and experimental results show that the interval propagation algorithm is valid and the mean bound is tight.
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