Hamiltonian Neural Networks for Robust Out-of-Time Credit Scoring
Javier Marín
TL;DR
The paper tackles the challenge of time-varying credit risk and concept drift by developing a Hamiltonian-inspired neural optimization framework that integrates physics-based dynamics (symplectic updates and energy normalization) with a loss that regularizes model parameters. Evaluated on the Freddie Mac SFLLD via out-of-time splits, the approach demonstrates superior AUC and temporal stability compared to a strong baseline like XGBoost, albeit at a cost to conventional accuracy metrics. The work highlights the potential of physics-inspired optimization to improve long-horizon, robust discrimination in credit scoring, and suggests avenues for hybrid models and improved interpretability to enhance practical adoption in regulated financial settings.
Abstract
This paper presents a novel credit scoring approach using neural networks to address class imbalance and out-of-time prediction challenges. We develop a specific optimizer and loss function inspired by Hamiltonian mechanics that better captures credit risk dynamics. Testing on the Freddie Mac Single-Family Loan-Level Dataset shows our model achieves superior discriminative power (AUC) in out-of-time scenarios compared to conventional methods. The approach has consistent performance between in-sample and future test sets, maintaining reliability across time periods. This interdisciplinary method spans physical systems theory and financial risk management, offering practical advantages for long-term model stability.
