IMSaT Ian Donald Lecture - The Complementarity Principle and the Cause of Human Error

Wednesday 27th May 2015

The Complementarity Principle and the Cause of Human Error

Professor John Senders

University of Toronto

Division of Imaging & Technology Seminar Series

When: Wednesday, 27 May, 2015 - 16:00

Where: Gannochy Trust Lecture Theatre

Professor John Senders will deliver the second IMSaT Ian Donald Lecture on Wednesday 27th May in the Gannochy Trust Lecture Theatre at 16.00 followed by a drinks reception in the promenade area.

John W. Senders is one of the pioneers of the field of Engineering Psychology, with a long and influential career spanning six decades as a psychologist and human factors engineer. He was one of the first scientists to apply mathematical models to human behaviour in applied settings, making many important contributions to the field throughout his varied and often eclectic research history. He has worked in many different capacities ranging from academic (as a psychologist, engineer, and even professor of law), to scientist in both industrial and military research labs, to private consultant, to expert witness.

His work has contributed to the advancement of theoretical understanding in areas which are fundamental to the field, including mental workload, attention and visual sampling, eye movements, queuing theory, control theory and human error modeling. The application of his work has had an impact in a diverse range of domains including the design of space vehicles, modeling of driver behaviour, highway safety, pilot behavior, airplane cockpit design, medication errors and patient safety, nuclear power plant safety, and even electronic publishing.

Prof. Senders has an extensive record of service on advisory boards, editorial boards, and research councils. He has been an avid teacher and mentor to countless graduate students in Engineering Psychology and Human Factors Engineering, and has helped to launch many careers in the field.

"I was born in Cambridge, Massachusetts in 1920. After being thrown out of Cambridge Latin school I was sent off to Antioch College and was thrown out after my first year. I retreated in disgrace to Harvard College and graduated in 1948 (by which time I had also become Chief Electronics Engineer of General Controls Co. in Boston). I was then employed by the USAF as Laboratory Engineer (and as Head of two other research Sections) at the USAF Aero-Medical Lab. in Dayton, Ohio, then as Head of Psychology at the Arctic AeroMed Lab. in Fairbanks Alaska. In 1957 I was invited to Honeywell Corp as Principal Research Scientist, lured in 1962 from there to Cambridge think-tank B.B.N. as Principal Scientist; thence to Brandeis Univ as Senior Res. Assoc & Lecturer, to M.I.T as Visiting Senior Lecturer of Mech. Eng.., whence I was invited to Univ. of Toronto as Professor of Industrial Eng. I have been THERE ever since."


Post hoc analysis of an error leads to two conflicting hypothetical causal mechanisms. Much as light can be dealt with as a wave or as a particle but not both, human error can be dealt with either as a purely probabilistic or as a caused event. I will present a brief summary of the complementarity and propose that some errors are caused and some just happen.

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