2020/05/22 by Dette, Holger, Heinrichs, Florian · 1 citation
#FOS: Mathematics #Statistics Theory (math.ST)
paper · doi:10.48550/arxiv.2005.11132
In the common time series model Xi,n = μ(i/n) + εi,n with non-stationary errors we consider the problem of detecting a significant deviation of the mean function μ from a benchmark g (μ) (such as the initial value μ(0) or the average trend ∫01 μ(t) dt). The problem is motivated by a more realistic modelling of change point analysis, where one is interested in identifying relevant deviations in a smoothly varying sequence of means (μ(i/n))i =1,… ,n and cannot assume that the sequence is piecewise constant. A test for this type of hypotheses is developed using an appropriate estimator for the integrated squared deviation of the mean function and the threshold. By a new concept of self-normalization adapted to non-stationary processes an asymptotically pivotal test for the hypothesis of a relevant deviation is constructed. The results are illustrated by means of a simulation study and a data example.