| Abstract: | Abstract. Business cycles in different regions of the United States tend to synchronize. This study investigates the reasons behind this synchronization of business cycles and the consequent formation of a national business cycle. Trade between regions may not be strong enough for one region to “drive” business cycle fluctuations in another region. This study suggests that regional business cycles synchronize due to a nonlinear “mode‐locking” process in which weakly coupled oscillating systems (regions) tend to synchronize. There is no definitive test for mode‐lock. However, simulations, correlations, Granger causality tests, tests for nonlinearities, vector autoregressions, and spectral analysis reveal modest econometric support for the regional mode‐locking hypothesis of business cycle synchronization. |
