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arXiv · 1910.05615

Real-time outlier detection for large datasets by RT-DetMCD

Bart De Ketelaere·Mia Hubert·Jakob Raymaekers·Peter J. Rousseeuw·Iwein Vranckx
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Abstract

Modern industrial machines can generate gigabytes of data in seconds, frequently pushing the boundaries of available computing power. Together with the time criticality of industrial processing this presents a challenging problem for any data analytics procedure. We focus on the deterministic minimum covariance determinant method (DetMCD), which detects outliers by fitting a robust covariance matrix. We construct a much faster version of DetMCD by replacing its initial estimators by two new methods and incorporating update-based concentration steps. The computation time is reduced further by parallel computing, with a novel robust aggregation method to combine the results from the threads. The speed and accuracy of the proposed real-time DetMCD method (RT-DetMCD) are illustrated by simulation and a real industrial application to food sorting.

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Bart De Ketelaere, Mia Hubert, Jakob Raymaekers, Peter J. Rousseeuw, Iwein Vranckx. 2019-10-12. Real-time outlier detection for large datasets by RT-DetMCD. https://doi.org/10.1016/j.chemolab.2020.103957

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