The Complexity of Signal Detection

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Authors: Kenneth Allendoerfer, PhD.
Ferne Friedman-Berg, PhD.
Shantanu Pai

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Air traffic controllers continually monitor the traffic situation in their sectors and take action when they detect potentially hazardous situations. Automation systems simultaneously and independently monitor the situation and provide alerts when the situation meets defined criteria. The decisions made by the controllers and the automation systems may agree or disagree. Signal Detection Theory (SDT) provides a theoretical framework for understanding how controllers and automation systems make these decisions. However, traditional SDT provides an incomplete explanation of decision-making in the real-world ATC situations. In this paper, we examine instances where controllers take actions independently of the alert and where controllers take actions in response to an alert, but delay their actions until more information is available. Results from this study are applicable to other domains where operators are tasked to monitor situations while simultaneously monitoring the output of an alerting system.