Cortés González, DanielOnieva Caracuel, EnriquePastor López, IkerTrinchera, LauraWu, Jian2025-03-132025-03-132024-11Cortés, D. G., Onieva, E., Pastor, I., Trinchera, L., & Wu, J. (2024). Portfolio construction using explainable reinforcement learning. Expert Systems, 41(11). https://doi.org/10.1111/EXSY.136670266-472010.1111/EXSY.13667http://hdl.handle.net/20.500.14454/2520While machine learning's role in financial trading has advanced considerably, algorithmic transparency and explainability challenges still exist. This research enriches prior studies focused on high-frequency financial data prediction by introducing an explainable reinforcement learning model for portfolio management. This model transcends basic asset prediction, formulating concrete, actionable trading strategies. The methodology is applied in a custom trading environment mimicking the CAC-40 index's financial conditions, allowing the model to adapt dynamically to market changes based on iterative learning from historical data. Empirical findings reveal that the model outperforms an equally weighted portfolio in out-of-sample tests. The study offers a dual contribution: it elevates algorithmic planning while significantly boosting transparency and interpretability in financial machine learning. This approach tackles the enduring ‘black-box’ issue and provides a holistic, transparent framework for managing investment portfolios.eng© 2024 The Author(s)Algorithmic transparencyExplainable reinforcement learningFinancePortfolio managementjournal article2025-03-131468-0394