Money demand in Japan and nonlinear cointegration

We estimate the long-run Japanese money demand function in a cointegration framework with two nonlinear functional forms that allow for the liquidity trap, and compare the results with the standard log-level functional form. In addition to the conventional linear cointegration techniques, we also use a recently developed procedure for nonlinear cointegration that allows the estimation of alternative functional forms under the same assumption regarding the trend properties of the nominal interest rate. The nonlinear functional forms outperform the log-level functional form based on out-of-sample prediction performance.