Convergence and Cointegration

This paper provides a new, uni¯ed, and °exible framework to measure and characterize convergence in prices. We formally de¯ne this notion and propose a model to represent a wide range of transition paths that converge to a common steady-state. Our framework enables the econometric measurement of such transi- tional behaviors and the development of testing procedures. Speci¯cally, we derive a statistical test to determine whether convergence exists and, if so, which type: as catching-up or steady-state. The application of this methodology to historic wheat prices results in a novel explanation of the convergence processes experienced during the 19th century.