Abstract
In this article we derive a parameter constancy test of a stationary vector autoregressive model against the hypothesis that the parameters of the model change smoothly over time. A single structural break is contained in this alternative hypothesis as a special case. The test is a generalization of a single-equation test of a similar hypothesis proposed in the literature. An advantage here is that the asymptotic distribution theory is standard. The performance of the tests is compared to that of generalized Chow-tests and found satisfactory in terms of both size and power.
Notes
1In this case, the boostrap method can be justified with asymptotic arguments since the statistics considered are smooth functions of sample moments, and they are also asymptotically pivotal (see Horowitz, Citation2001).