A conditional autoencoder for trading
Recent research by Gu, Kelly, and Xiu (GKX, 2019) developed an asset pricing model based on the exposure of securities to risk factors. It builds on the concept of data-driven risk factors that we discussed in Chapter 13, Data-Driven Risk Factors and Asset Allocation with Unsupervised Learning, when introducing PCA as well as the risk factor models covered in Chapter 4, Financial Feature Engineering – How to Research Alpha Factors. They aim to show that the asset characteristics used by factor models to capture the systematic drivers of "anomalies" are just proxies for the time-varying exposure to risk factors that cannot be directly measured. In this context, anomalies are returns in excess of those explained by the exposure to aggregate market risk (see the discussion of the capital asset pricing model in Chapter 5, Portfolio Optimization and Performance Evaluation).
The Fama-French factor models discussed in Chapter 4 and...