🤖 AI Summary
This work addresses the challenge of root cause localization in time-varying dynamic systems with lag effects and memory properties—such as energy systems—where anomalies exhibit complex temporal dependencies. For the first time, the authors extend a strictly causal root cause analysis framework to such systems, introducing two truncation strategies to manage infinite-time dependency graphs: one preserving the original causal mechanisms and the other employing mechanism approximation. By integrating causal graph modeling with a data generation approach tailored to energy consumption peak scenarios, the proposed method is evaluated in a simulated factory environment. Results demonstrate that, given sufficient lag order, the approach accurately identifies the spatiotemporal origins of anomalies, while also quantifying the performance trade-offs introduced by mechanism approximation.
📝 Abstract
Root-cause analysis in controlled time dependent systems poses a major challenge in applications. Especially energy systems are difficult to handle as they exhibit instantaneous as well as delayed effects and if equipped with storage, do have a memory. In this paper we adapt the causal root-cause analysis method of Budhathoki et al. [2022] to general time-dependent systems, as it can be regarded as a strictly causal definition of the term"root-cause". Particularly, we discuss two truncation approaches to handle the infinite dependency graphs present in time-dependent systems. While one leaves the causal mechanisms intact, the other approximates the mechanisms at the start nodes. The effectiveness of the different approaches is benchmarked using a challenging data generation process inspired by a problem in factory energy management: the avoidance of peaks in the power consumption. We show that given enough lags our extension is able to localize the root-causes in the feature and time domain. Further the effect of mechanism approximation is discussed.