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Co-Training Realized Volatility Prediction Model with Neural Distributional Transformation

Co-Training Realized Volatility Prediction Model with Neural Distributional Transformation ArXiv ID: 2310.14536 “View on arXiv” Authors: Unknown Abstract This paper shows a novel machine learning model for realized volatility (RV) prediction using a normalizing flow, an invertible neural network. Since RV is known to be skewed and have a fat tail, previous methods transform RV into values that follow a latent distribution with an explicit shape and then apply a prediction model. However, knowing that shape is non-trivial, and the transformation result influences the prediction model. This paper proposes to jointly train the transformation and the prediction model. The training process follows a maximum-likelihood objective function that is derived from the assumption that the prediction residuals on the transformed RV time series are homogeneously Gaussian. The objective function is further approximated using an expectation-maximum algorithm. On a dataset of 100 stocks, our method significantly outperforms other methods using analytical or naive neural-network transformations. ...

October 23, 2023 · 2 min · Research Team

Latent Factor Analysis in Short Panels

Latent Factor Analysis in Short Panels ArXiv ID: 2306.14004 “View on arXiv” Authors: Unknown Abstract We develop a pseudo maximum likelihood method for latent factor analysis in short panels without imposing sphericity nor Gaussianity. We derive an asymptotically uniformly most powerful invariant test for the number of factors. On a large panel of monthly U.S. stock returns, we separate month after month systematic and idiosyncratic risks in short subperiods of bear vs. bull market. We observe an uptrend in the paths of total and idiosyncratic volatilities. The systematic risk explains a large part of the cross-sectional total variance in bear markets but is not driven by a single factor and not spanned by observed factors. ...

June 24, 2023 · 1 min · Research Team