Comparative analysis of nonparametric change-point detectors commonly used in hydrology |
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| Authors: | Changrang Zhou Ronald van Nooijen Alla Kolechkina Markus Hrachowitz |
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| Institution: | 1. Water Management Department, Faculty of Civil Engineering and Geosciences, Delft University of Technology , Delft, Netherlands C.Zhou-1@tudelft.nl;3. Water Management Department, Faculty of Civil Engineering and Geosciences, Delft University of Technology , Delft, Netherlands |
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| Abstract: | ABSTRACT Several commonly-used nonparametric change-point detection methods are analysed in terms of power, ability and accuracy of the estimated change-point location. The analysis is performed with synthetic data for different sample sizes, two types of change and different magnitudes of change. The methods studied are the Pettitt method, a method based on the Cramér von Mises (CvM) two-sample test statistic and a variant of the CUSUM method. The methods differ considerably in behaviour. For all methods the spread of estimated change-point location increases significantly for points near one of the ends of the sample. Series of annual maximum runoff for four stations on the Yangtze River in China are used to examine the performance of the methods on real data. It was found that the CvM-based test gave the best results, but all three methods suffer from bias and low detection rates for change points near the ends of the series. |
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| Keywords: | change-point detection Pettitt test Cramér von Mises test CUSUM test power ability uncertainty |
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