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Methods and Algorithms for Robust Filtering

  • Ursula Gather
  • Roland Fried

Abstract

We discuss filtering procedures for robust extraction of a signal from noisy time series. Moving averages and running medians are standard methods for this, but they have shortcomings when large spikes (outliers) respectively trends occur. Modified trimmed means and linear median hybrid filters combine advantages of both approaches, but they do not completely overcome the difficulties. Improvements can be achieved by using robust regression methods, which work even in real time because of increased computational power and faster algorithms. Extending recent work we present filters for robust online signal extraction and discuss their merits for preserving trends, abrupt shifts and extremes and for the removal of spikes.

Key words

Signal extraction drift edge outlier update algorithm 

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Copyright information

© Springer-Verlag Berlin Heidelberg 2004

Authors and Affiliations

  • Ursula Gather
    • 1
  • Roland Fried
    • 1
  1. 1.Department of StatisticsUniversity of DortmundDortmundGermany

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