Pruning Bayesian Networks for Computationally Tractable Multi-Model Calibration

Nicolas Gratius^*Mario BergésBurcu Akinci

• Carnegie Mellon University, Pittsburgh, United States

Anomaly response in aerospace systems increasingly relies on multi-model analysis in digital twins to replicate the system's behaviors and inform decisions. However, computer model calibration methods are typically deployed on individual models and are limited in their ability to capture dependencies across models. In addition, model heterogeneity has been a significant issue in integration efforts. Bayesian Networks are well suited for multi-model calibration tasks as they can be used to formulate a mathematical abstraction of model components and encode their relationship in a probabilistic and interpretable manner. The computational cost of this method however increases exponentially with the graph complexity. In this work, we propose a graph pruning algorithm to reduce computational cost while minimizing the loss in calibration ability by incorporating domain-driven metrics for selection purposes. We implement this method using a Python wrapper for BayesFusion software and show that the resulting prediction accuracy outperforms existing pruning approaches which rely primarily on statistics.