Search effort and the detection of faults
Jim Q. Smith · British Journal of Mathematical and Statistical Psychology · 1981
A Bayes decision approach is adopted to give predictive models for the behaviour of an inspector or inspectors searching for an unlikely fault. The associated probability of the detection of such an unlikely fault is found and is related to the inspector's prior beliefs, losses and personal model when he or she is in various environments. These theoretical probabilities of detection that assume ‘sensible’ action from the inspector are found, generally, to be dramatically smaller than the probabilities obtained from the assumption of efficient search. Thus the paper explains why events with associated minute ‘probabilities’ seem to occur regularly in practice.