Bayesian Forecasting of Stock Returns on the JSE using Simultaneous Graphical Dynamic Linear Models

Nelson Kyakutwika; Bruce Bartlett

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arXiv · 2307.08665

Bayesian Forecasting of Stock Returns on the JSE using Simultaneous Graphical Dynamic Linear Models

Nelson Kyakutwika·Bruce Bartlett

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Abstract

Cross-series dependencies are crucial in obtaining accurate forecasts when forecasting a multivariate time series. Simultaneous Graphical Dynamic Linear Models (SGDLMs) are Bayesian models that elegantly capture cross-series dependencies. This study forecasts returns of a 40-dimensional time series of stock data from the Johannesburg Stock Exchange (JSE) using SGDLMs. The SGDLM approach involves constructing a customised dynamic linear model (DLM) for each univariate time series. At each time point, the DLMs are recoupled using importance sampling and decoupled using mean-field variational Bayes. Our results suggest that SGDLMs forecast stock data on the JSE accurately and respond to market gyrations effectively.

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BibTeX RIS

Nelson Kyakutwika, Bruce Bartlett. 2023-07-07. Bayesian Forecasting of Stock Returns on the JSE using Simultaneous Graphical Dynamic Linear Models. https://arxiv.org/abs/2307.08665

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