Imajo, K., K. Minami, K. Ito, and K. Nakagawa. “Deep Portfolio Optimization via Distributional Prediction of Residual Factors”. Proceedings of the AAAI Conference on Artificial Intelligence, vol. 35, no. 1, May 2021, pp. 213-22, https://ojs.aaai.org/index.php/AAAI/article/view/16095.