ABSTRACTS OF ARTICLES OF THE JOURNAL "INFORMATION TECHNOLOGIES".
No. 4. Vol. 31. 2025

DOI: 10.17587/it.31.191-198

S. A. Imashev, Ph.D., Leading Researcher, E . À. Lazareva, Junior Researcher,
Research Station of the Russian Academy of Sciences in Bishkek, Bishkek, 720049, Kyrgyz Republic

Removal of Outliers in Geomagnetic Field Time Series Using the Hampel Filter

Received on 11.06.24
Accepted on 18.06.24

The paper presents a methodology for removing outliers in geomagnetic field time series using the Hampel filter. Quality metrics for binary data classification based on the confusion matrix demonstrated the effectiveness of the method and are comparable to those for similar algorithms used for outlier removal in 1-second magnetograms of the international INTERMAGNET network. Outliers identified using the developed methodology for the period 2019-2022 at the Ak-Suu base station exhibit a seasonal distribution pattern that correlates well with thunderstorm activity. The method enhances the quality of preliminary data processing for the geomagnetic monitoring network of the Research Station of the Russian Academy of Sciences, specifically by automating the procedure of magnetograms outliers filtering.
Keywords: geomagnetic field, time series, outliers, Hampel filter, confusion matrix, recurrence

Acknowledgements: This work was supported by the Federal State Budgetary Institution of Science Research Station Russian Academy of Sciences in Bishkek, project no. 1021052806454-2-1.5.1.

P. 191-198

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