This paper introduces a solution that combines the Kalman and particle filters to the challenging problem of estimating integrated volatility using high-frequency data where the underlying prices are perturbed by a mixture of random noise and price discreteness. An explanation is presented of how the proposed combined filtering approach is able to correct for bias due to this mixed-type microstructure effect. Simulation and empirical studies on the tick-by-tick trade price data for four US stocks in the year 2009 show that our method has clear advantages over existing high-frequency volatility estimation methods.
KEYWORDScombined filters, high-frequency data, integrated volatility, market microstructure noise, price discreteness
INTRODUCTIONThe last 15 years have seen growing interest in volatility estimation using high-frequency data. One challenge when making inferences using high-frequency data is the presence of a market microstructure effect that causes the traditional realized volatility (RV) method to fail. 1 The market microstructure effect may be attributable to, among other causes, bid-ask bounce, adverse selection due to asymmetry of information for different traders, dealer's inventory control, and price discreteness. In contrast to those random effects that can be deemed measurement errors, the effect that stems from price discreteness is of a nonlinear nature. Although the work described in the existing literature has usually treated the two kinds of effect somewhat separately, they are both present in real data and pose a great challenge to volatility estimation using high-frequency data. Subsampling (eg, at an adhoc 5-minute frequency as suggested by Andersen et al 2 ) may mitigate the microstructure effect to a certain degree; however, it is one of the first principles of statistics that one should not throw away a large amount of data. In this paper, we address the problem by proposing an approach that combines the Kalman and particle filters.The study of price discreteness can be dated back to the 1980s. If one takes price discreteness as rounding errors, then explicitly characterizing the effect of rounding on the latent "true" asset returns becomes surprisingly difficult, except under specific parametric Brownian/geometric Brownian models (cf the work of Campbell et al 3 ). In particular, under the parametric Brownian/geometric Brownian setup for the latent "true" price, Ball, 4 Gottlieb and Kalay, 5 and Harris, 6 among others, studied the effect of price discreteness on estimation of the volatility of the latent true price process. For models other than those that take price discreteness as rounding errors and are related to volatility estimation, see, eg, the ordered probit model in the work of Hausman et al 7 and the barrier models in the works of Marsh and Rosenfeld 8 and Cho and Frees. 9Appl Stochastic Models Bus Ind. 2019;35:603-623.wileyonlinelibrary.com/journal/asmb