Goodness-of-fit test for ergodic diffusions by discrete-time observations: an innovation martingale approach

Abstract

We consider a nonparametric goodness-of-fit test problem for the drift coefficient of one-dimensional ergodic diffusions. Our test is based on the discrete-time observation of the processes, and the diffusion coefficient is a nuisance function which is estimated in some sense in our testing procedure. We prove that the limit distribution of our test is the supremum of the standard Brownian motion, and thus our test is asymptotically distribution free. We also show that our test is consistent under any fixed alternatives.

Keywords:

• ergodic diffusion process
• discrete-time observation
• invariance principle
• asymptotically distribution-free test

Acknowledgements

This work was supported by MIUR 2006 Grant and ISM Cooperative Research Program.