Relation of motivation intensity, stress levels and human performance: A human reliability experiment

The human reliability analysis (HRA) has long been focusing on analyzing the context influence on human performance and exploring the mechanism behind human undesirable behaviors. However, when it comes to such analysis, most HRA methods are limited to a set of risk factors in the context while ignoring the psychological process that drives human behaviors. In this study, we concentrate on two main psychological factors, motivation and stress, that could have significant impact on the operators' performance on a task. An experiment was designed to explore the relationship between motivation intensity and human error probability (HEP) under different stress levels. The data result showed significant difference in HEP under different stress levels. Also, a quadratic curve relationship was found between motivation and HEP, which fits with the Yerkes-Dodson Law as well. Human reliability can thus be further analyzed with using the relationship model between motivation intensity, stress level and HEP.