MAPLE: Efficient and Diverse Multi-Alpha Generation for Portfolio Construction
This work addresses the limitation of conventional deep learning approaches for stock ranking, which typically produce a single alpha signal and lack explicit control over correlations among multiple alphas, resulting in insufficient portfolio diversity. The authors propose MAPLE, a novel framework that, within a single training run, jointly incorporates a unified capacity-scaled prediction head, an extreme-rank weighted listwise loss, and an explicit diversity regularizer to enable controllable generation of multiple alpha signals with desired correlation structures—all within a single model. Notably, MAPLE achieves this without increasing architectural complexity and is compatible with various backbone networks. Evaluated across four major equity markets in the U.S., China, and Japan, MAPLE significantly outperforms nine baselines, achieving up to 55× fewer parameters and 2.5× faster training while improving Sharpe ratios by 10–23% and Calmar ratios by 17–43%.