Probabilistic weighted Dirichlet process mixture with an application to stochastic volatility models

Abstract In this article, we propose a flexible Bayesian modelling framework and investigate the probabilistic weighted Dirichlet process mixture (pWDPM). The construction and properties of a probabilistic weight function are illustrated. The advantage of the pWDPM under the log‐squared transformed stochastic volatility (SV) model is demonstrated. We achieve greater modelling flexibility by relaxing the distributional assumption of the error term. Bayesian inference for the pWDPM under SV and sampling procedures are provided. The performance of the pWDPM is evaluated using simulation studies and empirical results. Both computational efficiency and model accuracy are achieved through the pWDPM.