Related Experiment Video
Updated: Mar 7, 2026

Applications of EEG Neuroimaging Data: Event-related Potentials, Spectral Power, and Multiscale Entropy
Published on: June 27, 2013
Bubble Entropy: An Entropy Almost Free of Parameters
George Manis1, Md Aktaruzzaman2, Roberto Sassi2
1Department of Computer Science and Engineering, University of Ioannina, Ioannina, Greece.
We introduce Bubble Entropy, a new method for estimating entropy that minimizes parameter selection. This novel approach offers enhanced stability and descriptive power for analyzing physiological signals like HRV.
Area of Science:
- Complexity Science
- Biomedical Signal Processing
- Information Theory
Background:
- Entropy estimation in physiological signals is crucial for understanding system dynamics.
- Traditional entropy measures often depend heavily on parameter selection, influencing results.
- Parameter dependency can lead to application-specific tuning and subjective interpretations.
Purpose of the Study:
- To propose a novel entropy definition, Bubble Entropy, that reduces parameter dependency.
- To enhance the stability and descriptive power of entropy estimation for physiological data.
- To overcome limitations of existing entropy measures influenced by parameter choices.
Main Methods:
- Bubble Entropy is based on permutation entropy, utilizing the bubble sort algorithm for vector ordering.
- Instead of ranking vectors, it counts the number of swaps performed by bubble sort.
- This creates a coarse-grained distribution for entropy calculation, minimizing parameter influence.
Main Results:
- Bubble Entropy demonstrated remarkable stability across real and synthetic Heart Rate Variability (HRV) signals.
- The new method exhibited superior descriptive and discriminating power compared to established entropy definitions.
- Parameter influence was significantly reduced, with the scale factor completely eliminated.
Conclusions:
- Bubble Entropy offers a robust and almost parameter-free approach to entropy estimation.
- The method's reduced parameter importance (embedding dimension 'm') and eliminated scale factor ('r') improve objectivity.
- This advancement provides a more reliable and less subjective tool for physiological signal analysis.
More Related Videos
Related Concept Videos
Entropy
Entropy
When an ideal gas expands isothermally, the disorder in the gas increases. From the molecular perspective, the gas molecules have more volume to move around in.
Consider an infinitesimal step in the expansion, which...
Entropy and the Second Law of Thermodynamics
The relation between entropy and disorder can be illustrated with the example of the phase change of ice to water. In ice, the molecules are located at specific sites giving a solid state, whereas, in a liquid form, these molecules are much freer to move. The molecular arrangement has therefore become more randomized. Although the change in average...
Entropy and the Second Law of Thermodynamics
The Entropy as a State Function
The Second Law of Thermodynamics

