Ritik Roshan Giri , Suchandan Kayal , Javier E. Contreras-Reyes
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引用次数: 0
Abstract
Several complexity measures have been proposed to understand the complexity of physiological, financial, biological, and other time series that involve real-world problems. Permutation entropy (PE), fractal dimension and Lyapunov exponents are such complexity parameters out of many. The enormous use of PE in specifying complexity of chaotic time series motivates us to propose an alternative complexity parameter in this paper, known as the permutation extropy (PExt) measure. Here, we combine the ideas behind the PE and extropy to construct this new measure. We then validate the proposed measure using logistic, Hénon and Burger chaotic maps. Further, we apply the proposed complexity measure to study the impact of Covid-19 on financial stock market time series data set and to analyze the situation of Covid in India across different phases, considering the WHO data set. The proposed measure demonstrates robustness, fast calculation and invariant with respect to monotonous nonlinear transformation like PE.
期刊介绍:
Physica A: Statistical Mechanics and its Applications
Recognized by the European Physical Society
Physica A publishes research in the field of statistical mechanics and its applications.
Statistical mechanics sets out to explain the behaviour of macroscopic systems by studying the statistical properties of their microscopic constituents.
Applications of the techniques of statistical mechanics are widespread, and include: applications to physical systems such as solids, liquids and gases; applications to chemical and biological systems (colloids, interfaces, complex fluids, polymers and biopolymers, cell physics); and other interdisciplinary applications to for instance biological, economical and sociological systems.