A sensitivity analysis for operator error

This paper conducts a sensitivity analysis for operator error. The analysis is conducted with respect to the type of probability distribution used to describe error occurrence because the major dilemma when including operator performance in a study of transportation systems is choosing a probability distribution that accurately describes the occurrence of operator error. The motivation for the approach taken in this paper is that data is difficult and expensive to collect. It is worthwhile to determine how much and what kind of data needs to be collected. With this point of view, the paper begins with a simple distribution for error occurrence. The result from a simple distribution is compared to the results from more complicated distributions. All the distributions are based on a consideration of human factors and operating environments. The analysis is carried out for a sample transportation system, and there is an accident only if there is an error and certain traffic conditions. Because of this complexity, the safety parameter (the expected number of accidents during the systems´ lifetime) is estimated by Monte Carlo methods.