M-ESTIMATION FOR A SPATIAL UNILATERAL AUTOREGRESSIVE MODEL WITH INFINITE VARIANCE INNOVATIONS

We study the limiting behavior of the <italic>M</italic>-estimators of parameters for a spatial unilateral autoregressive model with independent and identically distributed innovations in the domain of attraction of a stable law with index <italic>α</italic> ∈ (0, 2]. Both stationary and unit root models and some extensions are considered. It is also shown that self-normalized <italic>M</italic>-estimators are asymptotically normal. A numerical example and a simulation study are also given.