A Systematic Assessment of Operational Metrics for Modeling Operator Functional State

Jean-François Gagnon, Olivier Gagnon, Daniel Lafond, Mark Parent, Sébastien Tremblay


This paper addresses critical issues and reports key findings with regards to the development of participant-generic operator functional state (OFS) models in the context of cognitive work. Conceptually, this research is concerned with the nature of the relationship between the physiological state of individuals and human performance. Participants were physiologically monitored (cardiac, respiratory, and eye activity) during the execution a set of two cognitive tasks – n-back and visual search – for which there were two levels of difficulty. Levels of difficulty were associated with levels of mental workload. Performance on the tasks was also monitored and linked with OFS. Modeling of the relationship between physiological state and OFS involved systematic manipulation of three parameters: (1) size of smoothing window for performance, (2) performance decrement threshold for labelling functional and sub-functional states, and (3) the mode of classification being either prospective or descriptive. Modeling was performed using two types of classifiers. Results show that (1) models that use bio-behavioral data were capable of classifying performance on new participant data above chance, (2) levels of mental workload were better classified than OFS, (3) size of smoothing window had a significant impact on classifier performance, and (4) size of smoothing window, threshold values, and classifier type had a significant impact on sensitivity and specificity. Implications for the use of OFS models in operational contexts are discussed.


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Paper Citation

in Harvard Style

Gagnon J., Gagnon O., Lafond D., Parent M. and Tremblay S. (2016). A Systematic Assessment of Operational Metrics for Modeling Operator Functional State . In Proceedings of the 3rd International Conference on Physiological Computing Systems - Volume 1: PhyCS, ISBN 978-989-758-197-7, pages 15-23. DOI: 10.5220/0005921600150023

in Bibtex Style

author={Jean-François Gagnon and Olivier Gagnon and Daniel Lafond and Mark Parent and Sébastien Tremblay},
title={A Systematic Assessment of Operational Metrics for Modeling Operator Functional State},
booktitle={Proceedings of the 3rd International Conference on Physiological Computing Systems - Volume 1: PhyCS,},

in EndNote Style

JO - Proceedings of the 3rd International Conference on Physiological Computing Systems - Volume 1: PhyCS,
TI - A Systematic Assessment of Operational Metrics for Modeling Operator Functional State
SN - 978-989-758-197-7
AU - Gagnon J.
AU - Gagnon O.
AU - Lafond D.
AU - Parent M.
AU - Tremblay S.
PY - 2016
SP - 15
EP - 23
DO - 10.5220/0005921600150023