42nd Congress of the European Regional Science Association: "From Industry to Advanced Services - Perspectives of European Metropolitan Regions", August 27th - 31st, 2002, Dortmund, Germany
In this paper we discuss the specification process of a spatial econometric model. There are a lot of results available in a time series context, which form a very well structured phase, but little has been said when the domain of the model is the Space in relation to this question. There are several points that merit some special attention. For example, it is not clear if the concepts of integration and cointegration are also relevant in a spatial context. Moreover, at this moment we do not have any specific criteria in order to solve the selection of the variables. This weakness lead us to another question, which is related to the correlation problem: Which kind of cross-sectional dynamics could be allowed in a spatial specification? At present, in case of finding spatial autocorrelation in a model we try to model it immediatly, without considerer that if it may reflect a previous specification error. Finally, there is the problem of the outliers which are of paramount importance in time series but just unkown in a spatial context. We will discuss each one of this topics making reference to a general specification and looking also at the final stage of model selection.