Bayesian Solutions for the Factor Zoo: We Just Ran Two Quadrillion Models

Bryzgalova, S, Huang, J and Julliard, C (2023) Bayesian Solutions for the Factor Zoo: We Just Ran Two Quadrillion Models. Journal of Finance, 78 (1). pp. 487-557. ISSN 0022-1082

Abstract

We propose a novel framework for analyzing linear asset pricing models: simple, robust, and applicable to high-dimensional problems. For a (potentially misspecified) stand-alone model, it provides reliable price of risk estimates for both tradable and non-tradable factors, and detects those weakly identified. For competing factors and (possibly non-nested) models, the method automatically selects the best specification – if a dominant one exists – or provides a Bayesian model averaging, BMA-SDF, if there is no clear winner. We analyze 2.25 quadrillion models generated by a large set of factors and find that the BMA-SDF outperforms existing models in- and out-of-sample.