Abstract
In this study, a Fuzzy Success Index Method (FSIM) is developed to estimate human reliability. It first uses the fuzzy MCDM technique to aggregate the weightings and the success influence ratings of various PSFs in the task situation to obtain the Fuzzy Success Index (FSI) which represents the decision-makers' belief of the effect of various PSFs to the task success. By considering that the pooled discrete fuzzy subset of the FSI as the causal event and the known human reliability as the resultant event, a fuzzy relation between the two events of a reference task can be obtained. After evaluating the FSI of the assessing task, the fuzzy composition of the discrete fuzzy subset of the FSI and the fuzzy relation can be used to estimate the task's human reliability. This method can take into account the variability of human performance as well as the biases inherent within individual judgment. © 1992.