## Bernoulli

• Bernoulli
• Volume 19, Number 5B (2013), 2715-2749.

### A test for stationarity based on empirical processes

#### Abstract

In this paper we investigate the problem of testing the assumption of stationarity in locally stationary processes. The test is based on an estimate of a Kolmogorov–Smirnov type distance between the true time varying spectral density and its best approximation through a stationary spectral density. Convergence of a time varying empirical spectral process indexed by a class of certain functions is proved, and furthermore the consistency of a bootstrap procedure is shown which is used to approximate the limiting distribution of the test statistic. Compared to other methods proposed in the literature for the problem of testing for stationarity the new approach has at least two advantages: On one hand, the test can detect local alternatives converging to the null hypothesis at any rate $g_{T}\to0$ such that $g_{T}T^{1/2}\to\infty$, where $T$ denotes the sample size. On the other hand, the estimator is based on only one regularization parameter while most alternative procedures require two. Finite sample properties of the method are investigated by means of a simulation study, and a comparison with several other tests is provided which have been proposed in the literature.

#### Article information

Source
Bernoulli, Volume 19, Number 5B (2013), 2715-2749.

Dates
First available in Project Euclid: 3 December 2013

https://projecteuclid.org/euclid.bj/1386078618

Digital Object Identifier
doi:10.3150/12-BEJ472

Mathematical Reviews number (MathSciNet)
MR3160569

Zentralblatt MATH identifier
1281.62183

#### Citation

Preuß, Philip; Vetter, Mathias; Dette, Holger. A test for stationarity based on empirical processes. Bernoulli 19 (2013), no. 5B, 2715--2749. doi:10.3150/12-BEJ472. https://projecteuclid.org/euclid.bj/1386078618

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