Root Cause Analysis of Measurement and Mechanistic Anomalies

TL;DR

This paper introduces a causal model to differentiate measurement errors from mechanism shifts in anomalies, enabling more accurate root cause analysis and classification.

Contribution

It formally defines a causal framework capturing both anomaly types and develops an efficient inference method for localization and classification.

Findings

State-of-the-art performance in root cause localization

Robust classification of anomaly types on synthetic and real data

Effective distinction between measurement errors and mechanism shifts

Abstract

Root cause analysis of anomalies aims to identify how and why a sample deviates from the normal process. Existing methods primarily focus on telling which features are responsible, ignoring that anomalies can arise through two fundamentally different processes: measurement errors, where the sample is generated normally but one or more values is recorded incorrectly, and mechanism shifts, where the causal process that generated the sample was changed. While measurement errors can often be safely corrected, mechanistic anomalies require careful consideration. In this paper, we formally define a causal model that explicitly captures both types by treating outliers as latent interventions on latent ("true") and observed ("measured") variables and show under which conditions the distinction is possible. Based on this model, we develop an efficient inference procedure for localizing root causes and distinguishing anomaly types. Experiments on synthetic and real-world data show that our method provides state-of-the-art and highly robust performance in both root cause localization and classification of anomaly types.