🤖 AI Summary
This study addresses a key limitation in traditional asset pricing—portfolio construction based solely on point forecasts, which ignores estimation uncertainty at the individual asset level. The paper proposes a novel approach that explicitly incorporates asset-specific uncertainty into machine learning–driven asset ranking by replacing point predictions with uncertainty-adjusted prediction intervals for expected returns. Integrating multiple machine learning models with uncertainty quantification techniques, the method remains robust even under partially misspecified or imperfect uncertainty estimates. Empirical results demonstrate that this strategy significantly enhances portfolio performance, particularly when used with complex predictive models, primarily through a substantial reduction in portfolio volatility.
📝 Abstract
Machine learning is central to empirical asset pricing, but portfolio construction still relies on point predictions and largely ignores asset-specific estimation uncertainty. We propose a simple change: sort assets using uncertainty-adjusted prediction bounds instead of point predictions alone. Across a broad set of ML models and a U.S. equity panel, this approach improves portfolio performance relative to point-prediction sorting. These gains persist even when bounds are built from partial or misspecified uncertainty information. They arise mainly from reduced volatility and are strongest for flexible machine learning models. Identification and robustness exercises show that these improvements are driven by asset-level rather than time or aggregate predictive uncertainty.