Testing for Cointegration between House Prices and Economic Fundamentals

Economic theory predicts three possibilities for the cointegration relationship between house prices and economic fundamentals: linear cointegration, nonlinear cointegration and no cointegration. In contrast, the empirical literature has only examined linear cointegration. This article argues that ignoring nonlinear cointegration may lead to misleading conclusions that no cointegration exists between house prices and the fundamentals. To illustrate this point, I test for cointegration for ten U.S. cities and find that only one city shows evidence of linear cointegration. Further analysis using the two‐step testing procedure yields evidence of nonlinear cointegration for six other cities. Still, there are three cities left out without evidence of nonlinear cointegration. Further studies are needed to test for other forms of nonlinear cointegration before a conclusion of no cointegration can be reached for the remaining three cities.