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Mapping Cortical Dynamics Using Simultaneous MEG/EEG and Anatomically-constrained Minimum-norm Estimates: an Auditory Attention Example
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Point estimates, Simpson's paradox, and nonergodicity in biological sciences
Madhur Mangalam1, Damian G Kelty-Stephen2
1Department of Physical Therapy, Movement and Rehabilitation Sciences, Northeastern University, Boston, MA, USA.
Neuroscience and Biobehavioral Reviews
|February 23, 2021
Summary
Modern science assumes ergodicity, but evidence shows this is often violated. This research proposes new statistical methods to accurately measure nonergodicity, enabling better understanding of complex biological and psychological behaviors.
Area of Science:
- Biomedical sciences
- Behavioral sciences
- Psychological sciences
Background:
- Current scientific inference relies on the ergodic assumption.
- This assumption posits that sample averages predict individual behavior.
- Recent evidence reveals systematic violations of ergodicity across disciplines.
Purpose of the Study:
- To review the impact of ergodic assumption violations on scientific progress.
- To propose a practical methodology for addressing nonergodicity.
- To facilitate the study of nonstationary, far-from-equilibrium processes.
Main Methods:
- Review of empirical evidence on nonergodicity.
- Advocacy for statistical measures encoding nonergodicity.
- Conceptual framework for a paradigm shift in scientific inference.
Main Results:
- Identified significant costs to scientific progress due to the ergodic assumption.
- Proposed statistical measures capable of quantifying nonergodicity.
- Outlined a path towards investigating complex biological and psychological phenomena.
Conclusions:
- Violations of the ergodic assumption are prevalent and hinder scientific understanding.
- Adopting statistical measures for nonergodicity is crucial for scientific advancement.
- This approach enables the study of emergent and creative behaviors in biological and psychological systems.
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