We present the spmat command for creating, managing, and storing spatial-weighting matrices, which are used to model interactions between spatial or more generally cross-sectional units. spmat can store spatial-weighting matrices in a general and banded form. We illustrate the use of the spmat...

Weighting matrices are typically assumed to be exogenous. However, in many cases this exogeneity assumption may not be reasonable. In these cases, typical model specifications and corresponding estimation procedures will no longer be valid. In this paper we specify a reasonably general spatial...