Special Session 51: Ordinal Symbolic Dynamics and Applications

Ordinal symbolic dynamics is a promising new approach to the investigation of time series and the systems behind them, with the important properties of being conceptually simple and relatively robust with respect to noise. The idea behind it is to consider the order relation between the values of a time series instead of the values themselves. Roughly speaking, a given time series is transformed into a series of order patterns describing the ups and downs of the original series. Then the distribution of ordinal patterns obtained is the basis of the analysis. Since Bandt and Pompe introduced permutation entropy in their celebrated paper in 2002, the idea has been intensively discussed. For example, there are interesting results and open questions concerning the relation of permutation entropy to conventional ergodic concepts in dynamical systems like KolmogorovSinai entropy. On the other hand, the tools of ordinal symbolic dynamics are being used in real time series analysis with a remarkable success, e.g. for identifying and discriminating different brain states in epilepsy research and in anesthesiology, for heart rate analysis, and for testing independence. The purpose of the special session is to bring together researchers working on ordinal symbolic dynamics and related topics, in order to discuss new developments in theory and applications, and to celebrate the first ten years of the field!