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Related Experiment Video

Updated: Jul 17, 2026

A Vibrotactile Feedback Device for Seated Balance Assessment and Training

A Vibrotactile Feedback Device for Seated Balance Assessment and Training

Published on: January 20, 2019

Training for vigilance: using predictive power to evaluate feedback effectiveness.

James L Szalma¹, Peter A Hancock, Joel S Warm

¹Department of Psychology, University of Central Florida, P.O. Box 161390, Orlando 32816-1390, USA. jszalma@mail.ucf.edu

|January 24, 2007

Summary

Knowledge of results (KR) training improved vigilance by reducing false alarms but did not improve signal detection. New metrics, positive and negative predictive power (PPP and NPP), offer a more complete assessment of vigilance training effectiveness.

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Movement Retraining using Real-time Feedback of Performance

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Last Updated: Jul 17, 2026

A Vibrotactile Feedback Device for Seated Balance Assessment and Training

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Published on: January 20, 2019

Movement Retraining using Real-time Feedback of Performance

Movement Retraining using Real-time Feedback of Performance

Published on: January 17, 2013

Area of Science:

Human Factors
Cognitive Psychology
Signal Detection Theory

Background:

Vigilance training is crucial for monitoring tasks.
Knowledge of results (KR) is commonly used but its scheduling effects are understudied.
Traditional metrics like hits and false alarms are insufficient for evaluating training.

Purpose of the Study:

To investigate the impact of continuous and partial KR on vigilance accuracy.
To introduce and utilize positive and negative predictive power (PPP and NPP) for assessing vigilance training effectiveness.

Main Methods:

Examined the effects of continuous KR, partial KR, and no-KR control conditions.
Applied signal detection theory (SDT) and diagnosticity measures, including PPP and NPP.

Main Results:

KR led to conservative responding without improving sensitivity.
Both continuous and partial KR enhanced PPP.
KR selectively impaired NPP.

Conclusions:

KR presents a trade-off between reducing misses and false alarms.
SDT combined with PPP/NPP provides a comprehensive evaluation of vigilance performance.
PPP and NPP are valuable diagnostic tools for the human factors community.