Efficient parameter estimation for parabolic SPDEs based on a log-linear model for realized volatilities
Markus Bibinger, Patrick Bossert
TL;DR
The paper tackles parameter estimation for a one-dimensional parabolic SPDE observed at high frequency in time and space. It introduces a log-linear model for realized volatilities across spatial points and develops least-squares estimators for the curvature parameter and an intercept tied to the volatility, achieving asymptotically efficient rates with feasible confidence intervals. The authors prove central limit theorems for the estimators, derive explicit asymptotic variance-covariance matrices, and demonstrate substantial finite-sample efficiency gains over existing M-estimators through numerical comparisons and Monte Carlo simulations. The approach combines spectral SPDE analysis with a regression-based framework, offering practical and theoretically grounded tools for calibrating SPDEs from high-frequency data.
Abstract
We construct estimators for the parameters of a parabolic SPDE with one spatial dimension based on discrete observations of a solution in time and space on a bounded domain. We establish central limit theorems for a high-frequency asymptotic regime. The asymptotic variances are shown to be substantially smaller compared to existing estimation methods. Moreover, asymptotic confidence intervals are directly feasible. Our approach builds upon realized volatilities and their asymptotic illustration as response of a log-linear model with spatial explanatory variable. This yields efficient estimators based on realized volatilities with optimal rates of convergence and minimal variances. We demonstrate efficiency gains compared to previous estimation methods numerically and in Monte Carlo simulations.
