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Measurement of the Directional Information Flow in fNIRS-Hyperscanning Data using the Partial Wavelet Transform Coherence Method
Published on: September 3, 2021
Tracking time-varying causality and directionality of information flow using an error reduction ratio test with
Yifan Zhao1, Steve A Billings, Hualiang Wei
1Department of Automatic Control and System Engineering, University of Sheffield, Sheffield, United Kingdom.
Physical Review. E, Statistical, Nonlinear, and Soft Matter Physics
|December 11, 2012
Summary
This study presents a new error reduction ratio-causality (ERR-causality) test to identify causal links between signals. This method effectively detects time-varying causality and interaction direction without complex modeling, outperforming traditional approaches.
Area of Science:
- Signal processing
- Causality analysis
- Biomedical engineering
Background:
- Traditional Granger causality methods require complete model fitting.
- Detecting time-varying and nonlinear causal relationships remains challenging.
- Understanding signal interactions is crucial in various scientific domains.
Purpose of the Study:
- Introduce a novel error reduction ratio-causality (ERR-causality) test.
- Enable detection and tracking of causal relationships between two signals.
- Overcome limitations of existing causality detection methods.
Main Methods:
- Developed an error reduction ratio-causality (ERR-causality) test.
- The method does not require fitting a complete model.
- It can detect linear or nonlinear causality and estimate time shifts.
Main Results:
- The ERR-causality test effectively detects time-varying causality direction.
- It successfully identifies the direction of interactions between signals.
- Demonstrated effectiveness in analyzing electroencephalograph signals during epileptic seizures.
Conclusions:
- The ERR-causality test offers a robust alternative for causality detection.
- It provides insights into time-varying and nonlinear causal dynamics.
- The method has practical applications in neuroscience and signal analysis.

