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arXiv · 2504.17352

The Riemannian Means Field Classifier for EEG-Based BCI Data

Anton Andreev·Grégoire Cattan·Marco Congedo
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Abstract

A substantial amount of research has demonstrated the robustness and accuracy of the Riemannian minimum distance to mean (MDM) classifier for all kinds of EEG-based brain--computer interfaces (BCIs). This classifier is simple, fully deterministic, robust to noise, computationally efficient, and prone to transfer learning. Its training is very simple, requiring just the computation of a geometric mean of a symmetric positive-definite (SPD) matrix per class. We propose an improvement of the MDM involving a number of power means of SPD matrices instead of the sole geometric mean. By the analysis of 20 public databases, 10 for the motor-imagery BCI paradigm and 10 for the P300 BCI paradigm, comprising 587 individuals in total, we show that the proposed classifier clearly outperforms the MDM, approaching the state-of-the art in terms of performance while retaining the simplicity and the deterministic behavior. In order to promote reproducible research, our code will be released as open source.

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Anton Andreev, Grégoire Cattan, Marco Congedo. 2025-04-24. The Riemannian Means Field Classifier for EEG-Based BCI Data. https://doi.org/10.3390/s25072305

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