TY  - JOUR
A1  - Marwan, Norbert
A1  - Kurths, Jürgen
T1  - Comment on "Stochastic analysis of recurrence plots with applications to the detection of deterministic signals" by Rohde et al. : [Physica D 237 (2008) 619-629]
N2  - In the recent article "Stochastic analysis of recurrence plots with applications to the detection of deterministic signals" (Physica D 237 (2008) 619-629), Rohde et al. stated that the performance of RQA in order to detect deterministic signals would be below traditional and well-known detectors. However, we have concerns about such a general statement. Based on our own studies we cannot confirm their conclusions. Our findings suggest that the measures of complexity provided by RQA are useful detectors outperforming well-known traditional detectors, in particular for the detection of signals of complex systems, with phase differences or signals modified due to the measurement process.
Y1  - 2009
UR  - http://www.sciencedirect.com/science/journal/01672789
U6  - https://doi.org/10.1016/j.physd.2009.04.018
SN  - 0167-2789
ER  - 
TY  - JOUR
A1  - Schinkel, Stefan
A1  - Marwan, Norbert
A1  - Dimigen, Olaf
A1  - Kurths, Jürgen
T1  - Confidence bounds of recurrence-based complexity measures
N2  - In the recent past, recurrence quantification analysis (RQA) has gained an increasing interest in various research areas. The complexity measures the RQA provides have been useful in describing and analysing a broad range of data. It is known to be rather robust to noise and nonstationarities. Yet, one key question in empirical research concerns the confidence bounds of measured data. In the present Letter we suggest a method for estimating the confidence bounds of recurrence-based complexity measures. We study the applicability of the suggested method with model and real- life data.
Y1  - 2009
UR  - http://www.sciencedirect.com/science/journal/03759601
U6  - https://doi.org/10.1016/j.physleta.2009.04.045
SN  - 0375-9601
ER  - 
TY  - JOUR
A1  - Zolotova, Nadezhda V.
A1  - Ponyavin, Dmitri I.
A1  - Marwan, Norbert
A1  - Kurths, Jürgen
T1  - Long-term asymmetry in the wings of the butterfly diagram
N2  - Aims. Sunspot distribution in the northern and southern solar hemispheres exibit striking synchronous behaviour on the scale of a Schwabe cycle. However, sometimes the bilateral symmetry of the Butterfly diagram relative to the solar equatorial plane breaks down. The investigation of this phenomenon is important to explaining the almost-periodic behaviour of solar cycles. Methods. We use cross-recurrence plots for the study of the time-varying phase asymmetry of the northern and southern hemisphere and compare our results with the latitudinal distribution of the sunspots. Results. We observe a long-term persistence of phase leading in one of the hemispheres, which lasts almost 4 solar cycles and probably corresponds to the Gleissberg cycle. Long-term variations in the hemispheric-leading do not demonstrate clear periodicity but are strongly anti-correlated with the long-term variations in the magnetic equator.
Y1  - 2009
UR  - http://www.aanda.org/
U6  - https://doi.org/10.1051/0004-6361/200811430
SN  - 0004-6361
ER  - 
TY  - JOUR
A1  - Schinkel, Stefan
A1  - Marwan, Norbert
A1  - Kurths, Jürgen
T1  - Brain signal analysis based on recurrences
N2  - The EEG is one of the most commonly used tools in brain research. Though of high relevance in research, the data obtained is very noisy and nonstationary. In the present article we investigate the applicability of a nonlinear data analysis method, the recurrence quantification analysis (RQA), to Such data. The method solely rests on the natural property of recurrence which is a phenomenon inherent to complex systems, such as the brain. We show that this method is indeed suitable for the analysis of EEG data and that it might improve contemporary EEG analysis.
Y1  - 2009
UR  - http://www.sciencedirect.com/science/journal/09284257
U6  - https://doi.org/10.1016/j.jphysparis.2009.05.007
SN  - 0928-4257
ER  -