TY  - JOUR
A1  - Ślęzak, Jakub
A1  - Burnecki, Krzysztof
A1  - Metzler, Ralf
T1  - Random coefficient autoregressive processes describe Brownian yet non-Gaussian diffusion in heterogeneous systems
T2  - New Journal of Physics
N2  - Many studies on biological and soft matter systems report the joint presence of a linear mean-squared displacement and a non-Gaussian probability density exhibiting, for instance, exponential or stretched-Gaussian tails. This phenomenon is ascribed to the heterogeneity of the medium and is captured by random parameter models such as ‘superstatistics’ or ‘diffusing diffusivity’. Independently, scientists working in the area of time series analysis and statistics have studied a class of discrete-time processes with similar properties, namely, random coefficient autoregressive models. In this work we try to reconcile these two approaches and thus provide a bridge between physical stochastic processes and autoregressive models.Westart from the basic Langevin equation of motion with time-varying damping or diffusion coefficients and establish the link to random coefficient autoregressive processes. By exploring that link we gain access to efficient statistical methods which can help to identify data exhibiting Brownian yet non-Gaussian diffusion.
KW  - diffusion
KW  - Langevin equation
KW  - Brownian yet non-Gaussian diffusion
KW  - diffusing diffusivity
KW  - superstatistics
KW  - autoregressive models
KW  - time series analysis
KW  - codifference
Y1  - 2019
UR  - https://publishup.uni-potsdam.de/frontdoor/index/index/docId/43793
SN  - 1367-2630
VL  - 21
PB  - Deutsche Physikalische Gesellschaft ; IOP, Institute of Physics
CY  - Bad Honnef und London
ER  -