On the theory of fuzzy signal detection: Theoretical and practical considerations and extensions

This work examines the foundations for and explores the implications of fuzzy signal detection (Fuzzy SDT), a theory that represents the marriage of two power-ful extant theories, fuzzy set theory and signal detection theory. Fuzzy SDT permits the modelling and prediction of human, machine, and human±machine performance in a wide range of settings. Fuzzy SDT exploits the strengths of each theory to provide new and dynamic insights into performance. Fuzzy SDT explic-itly recognizes that the binary decision states of classic signal detection represent two ends of a single continuum whose uncertainty decreases towards such end states and is maximized in its centre. It is shown how Fuzzy SDT has its origins in some more general concepts of human performance, and companion works are referenced which provide the mathematical foundation for Fuzzy SDT and its application in a speci®c domain. The present work examines the wider implica-tions of Fuzzy SDT by illustrating the relevance of fuzzi®cation in the larger cycle of design, con®guration, and use of technology. It also examines the broader concerns of the temporal relationship between signal and response, showing time to be a crucial, if neglected, dimension of action, the exploration and exploit-ation of which can produce a deeper understanding of human behaviour in psychology, machine behaviour in engineering and human±machine behaviour in ergonomics