Testing for Asymmetries and Anisotropies in Regional Economic Models

This paper develops a new methodology for estimating and testing the form of anisotropy of homogeneous spatial processes. We derive a generalised version of the isotropy test proposed by Arbia, Bee and Espa (2013) and analyse its properties in various settings. In light of this, we propose a new approach that allows one to estimate and test under mild conditions any form of anisotropy in homogeneous spatial processes. The power of the test is studied by means of Monte Carlo simulations performed both on regularly and irregularly spaced data. Finally, the method is used to analyse the soybeans yields in the US.