ASYMPTOTIC THEORY OF CEPSTRAL RANDOM FIELDS

作者：McElroy Tucker S^*; Holan Scott H

来源：Annals of Statistics, 2014, 42(1): 64-86.

DOI：10.1214/13-AOS1180

• Bayesian estimation
• cepstrum
• exponential spectral representation
• lattice data
• spatial statistics
• spectral density

Random fields play a central role in the analysis of spatially correlated data and, as a result, have a significant impact on a broad array of scientific applications. This paper studies the cepstral random field model, providing recursive formulas that connect the spatial cepstral coefficients to an equivalent moving-average random field, which facilitates easy computation of the autocovariance matrix. We also provide a comprehensive treatment of the asymptotic theory for two-dimensional random field models: we establish asymptotic results for Bayesian, maximum likelihood and quasi-maximum likelihood estimation of random field parameters and regression parameters. The theoretical results are presented generally and are of independent interest, pertaining to a wide class of random field models. The results for the cepstral model facilitate model-building: because the cepstral coefficients are unconstrained in practice, numerical optimization is greatly simplified, and we are always guaranteed a positive definite covariance matrix. We show that inference for individual coefficients is possible, and one can refine models in a disciplined manner. Our results are illustrated through simulation and the analysis of straw yield data in an agricultural field experiment.

• 出版日期2014-2