Published Methodology

Research & Validation

Explainable scoring, documented calibration provenance, and methodology built for scrutiny.

We treat research as product infrastructure. Methodology, calibration, and runtime behavior are designed to be interpretable by scientific, regulatory, and institutional stakeholders.

Method transparency

Scores map to acoustic evidence

Calibration integrity

Runtime and calibration stay aligned

Citation posture

Reference-backed methodology lineage

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Pierson (2026) VCAM Methodology

Speaker-calibrated vowel corridor norms derived from a native SAE speaker using a validated acoustic extraction pipeline. Calibration and runtime measurement use the same method — ensuring consistent, peer-reviewable results.

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The Mixed Norms Problem
Why legacy pooled vowel data creates systematic bias in speech scoring.
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From Hillenbrand to Pierson
The evolution of speaker-calibrated corridor methodology.
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Vowels Are the Blind Spot
Why SLPs and instructors underweight vowel training in accent modification.
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References

Hillenbrand, J., Getty, L. A., Clark, M. J., & Wheeler, K. (1995). Acoustic characteristics of American English vowels. JASA, 97(5), 3099–3111.

International Civil Aviation Organization. (2010). Manual on the implementation of ICAO language proficiency requirements (Doc 9835). ICAO.

Molesworth, B. R. C., & Estival, D. (2015). Miscommunication in general aviation: The influence of external factors on communication errors. Safety Science, 73, 73–79. https://doi.org/10.1016/j.ssci.2014.11.004

Peterson, G. E., & Barney, H. L. (1952). Control methods used in a study of the vowels. JASA, 24(2), 175–184.

Pierson, K. (2024). A review: Accent modification in aerospace and aviation. Human Factors in Aviation and Aerospace, 1(1), 93–98. https://doi.org/10.26650/hfaa.2024.1469611

Pierson, K. R., Simpson, K., Creaghead, N., & Herreras-Mercado, R. (2024). Vowel-centered accent modification in Mandarin Chinese-speaking pilot candidates. The International Journal of Aerospace Psychology, 34(1), 42–58. https://doi.org/10.1080/24721840.2023.2277462

Prinzo, O. V., et al. (2010). The impact of accented speech on pilot comprehension. FAA Human Factors Report.

Tiewtrakul, T., & Fletcher, S. R. (2010). The challenge of regional accents for aviation English language proficiency standards. Ergonomics, 53(2), 229–239.

Wu, Q., Molesworth, B. R. C., & Estival, D. (2019). An investigation into the factors that affect miscommunication between pilots and air traffic controllers in commercial aviation. The International Journal of Aerospace Psychology. https://doi.org/10.1080/24721840.2019.1610187

Proprietary methods protected under pending US patent applications.

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