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An R-Based Landscape Validation of a Competing Risk Model
Published on: September 16, 2022
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On the risk of extracting relevant information from random data
1The Hospital for Sick Children, Toronto, Ontario, Canada. l.garcia.d@gmail.com
Journal of Neural Engineering
|August 12, 2009
Summary
This study re-assesses near-infrared spectroscopy (NIRS) for decoding decision-making. The analysis reveals that the original study
Area of Science:
- Neuroscience
- Biomedical Engineering
- Signal Processing
Background:
- Re-assessment of a study using near-infrared spectroscopy (NIRS) to decode decision-making.
- Critique of the original study's feature selection methodology without independent validation.
- Introduction of a simulation using random time series to demonstrate potential risks.
Discussion:
- The original study performed feature selection on all data, risking overfitting.
- Lack of independent assessment in the original study hinders result validation.
- Simulation results mirrored the original study's findings, suggesting potential methodological flaws.
Key Insights:
- Classification accuracy from the original study may not represent genuine decision-making information.
- The methodology employed risks inflating classification accuracy through data dredging.
- Independent validation is crucial for reliable neuroimaging study findings.
Outlook:
- Further research should prioritize robust validation techniques in NIRS-based decision-making studies.
- Development of standardized protocols for feature selection and validation is recommended.
- Re-evaluation of existing NIRS studies with similar methodologies may be warranted.
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