The two-filter formula for smoothing and an implementation of the Gaussian-sum smoother

  • Genshiro Kitagawa
Time Series Analysis


A Gaussian-sum smoother is developed based on the two filter formula for smoothing. This facilitates the application of non-Gaussian state space modeling to diverse problems in time series analysis. It is especially useful when a higher order state vector is required and the application of the non-Gaussian smoother based on direct numerical computation is impractical. In particular, applications to the non-Gaussian seasonal adjustment of economic time series and to the modeling of seasonal time series with several outliers are shown.

Key words and phrases

Non-Gaussian smoother non-Gaussian filter Gaussian mixture nonstationary time series outliers seasonal adjustment 


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Copyright information

© The Institute of Statistical Mathematics 1994

Authors and Affiliations

  • Genshiro Kitagawa
    • 1
  1. 1.The Institute of Statistical MathematicsTokyoJapan

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