We derive a definition of linear cointegration for nonlinear stochastic processes using a martingale representation theorem. The result shows that stationary linear cointegrations can exhibit nonlinear dynamics, in contrast with the normal assumption of linearity. We propose a sequential...

Using Hall and Heyde's (1980) representation theorem, we show that the stationary co-integration relations of an integrated system are generally non-linear stochastic processes. We propose a sequential non-parametric procedure to test stationary co-integration relations for non-linear dynamics,...