Given a set of points in a plane, a spanning tree is a set of edges that connects all the points and contains no cycles. If each edge is weighted using the rectilinear distance metric, the rectilinear minimum spanning tree is a tree whose sum of edge weights is minimum. A naive approach to...

This paper defines isomorphism for network formation that is not mathematically isomorphic. Once the pattern of network formation is characterized, one can test for (i) location fixed effects, (ii) heterogeneity, (iii) private information allowing for long-term contracts. The paper provides...