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arXiv · 2306.12184

A Note on the Relation Between Balenzela's Algorithm for Two-Filter Formula for Smoothing and Information Filter

G. Kitagawa
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Abstract

Recent paper by Balenzuela et al. presented an exact algorithm for computing the posterior distribution of current and future observations given the current state, $p(x_n|y_n,\ldots ,y_N)$, which is required when computing fixed-interval smoother of the state by a two-filter formula. In this note, it will be shown that their algorithm is equivalent to the backward filter obtained by applying an information filter to the reverse state-space model. Although their algorithm is proposed for complex Gaussian mixture distribution models, in this note, we consider the case of simple state-space models with respect to filter computation.

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G. Kitagawa. 2023-06-21. A Note on the Relation Between Balenzela's Algorithm for Two-Filter Formula for Smoothing and Information Filter. https://arxiv.org/abs/2306.12184

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