AnDri: A System for Anomaly and Drift co-Detection

The presence of concept drift poses challenges for anomaly detection in time series. While anomalies are caused by undesirable changes in the data, differentiating abnormal changes from varying normal behaviours is difficult due to differing frequencies of occurrence, varying time intervals when normal patterns occur, and identifying similarity thresholds to separate the boundary between normal vs. abnormal sequences. Differentiating between concept drift and anomalies is critical for accurate analysis as studies have shown that the compounding effects of error propagation in downstream data analysis tasks lead to lower detection accuracy and increased overhead due to unnecessary model updates. Unfortunately, existing work has largely explored anomaly detection and concept drift detection in isolation. We develop AnDri, a system for Anomaly detection in the presence of Drift, and enables users to interactively co-explore the interaction of anomalies and drift. Our system demonstration provides two motivating scenarios that extend existing anomaly detection baselines with partial labels towards improved co-detection accuracy, and highlights the superiority of AnDri over these baselines.