Abstract
When HCR methodology is applied to quantify the human error probability, expertjudgements are needed to determine the values of performance shape factors (PSFs).In the present study, models using Fuzzy Inference System (FIS) are developed toestimate the values of PSFs. The expert judgments embedded in the HCR and THERPmethodology are used as the basis in the model development. The FIS models addressthe dependencies among factors that could affect the values of PSFs. The systematicapproach adopted in the FIS model can simplify the human reliability analysis and giveconsistent results. The FIS models are flexible to incorporate the new data or newfindings in the field of human reliability analysis.