arXiv Machine Learning By Oliver Urs Lenz, Matthijs van Leeuwen

Monotonic anomaly detection

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The paper introduces methods for monotonic anomaly detection, focusing on anomalies that exhibit high (or low) attribute values rather than arbitrary deviations. It proposes an asymmetrical distance measure using a ramp function for distance-based methods and a modified path length algorithm for Isolation Forest. Experiments on synthetic and real-life datasets demonstrate improved detection performance on datasets with monotonic attributes.

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