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Approximate entropy (ApEn) as a complexity measure
Open accessAbstract
Approximate entropy (ApEn) is a recently developed statistic quantifying regularity and complexity, which appears to have potential application to a wide variety of relatively short (greater than 100 points) and noisy time-series data. The development of ApEn was motivated by data length constraints commonly encountered, e.g., in heart rate, EEG, and endocrine hormone secretion data sets. We describe ApEn implementation and interpretation, indicating its utility to distinguish correlated stochastic processes, and composite deterministic/ stochastic models. We discuss the key technical idea that motivates ApEn, that one need not fully reconstruct an attractor to discriminate in a statistically valid manner—marginal probability distributions often suffice for this purpose. Finally, we discuss why algorithms to compute, e.g., correlation dimension and the Kolmogorov–Sinai (KS) entropy, often work well for true dynamical systems, yet sometimes operationally confound for general models, with the aid of visual representations of reconstructed dynamics for two contrasting processes.
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“Approximate entropy, a regularity statistic, was used as a feature because it quantifies the unpredictability of time-series data in a manner not captured by moment statistics [35].”
BackgroundMethodMulti-Scale Permutation Entropy for Audio Deepfake Detection
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Cortisol Dynamics, Quality of Life, and Fatigue following Traumatic Brain Injury in Childhood
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Metadata
- Authors
- Pincus, S.
- Venue
- Chaos: An Interdisciplinary Journal of Nonlinear Science
- Publisher
- AIP Publishing
- Published
- 1995-03-01
- Volume
- 5
- Issue
- 1
- Pages
- 110-117
- ISSN
- 1054-1500 (ISSN-L)
- 1089-7682
- OpenAlex
- W2031377725
- Cited by
- 1,213
- References
- 0
- FWCI
- 2.64
- Type
- journal article
- Language
- en
- Open access
- green
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