A Harris process to model stochastic volatility

Abstract

We present a tractable non-independent increment process which provides a high modeling flexibility. The process lies on an extension of the so-called Harris chains to continuous time being stationary and Feller. We exhibit constructions, properties, and inference methods for the process. Afterwards, we use the process to propose a stochastic volatility model with an arbitrary but fixed invariant distribution, which can be tailored to fit different applied scenarios. We study the model performance through simulation while illustrating its use in practice with empirical work. The model proves to be an interesting competitor to a number of short-range stochastic volatility models.