Expertfit: total support for simulation input modeling

We discuss the critical role of simulation input modeling in a successful simulation study. Two pitfalls in simulation input modeling are then presented and we explain how any analyst, regardless of their knowledge of statistics, can easily avoid these pitfalls through the use of the ExpertFit distribution-fitting software. We use a set of real-world data to demonstrate how the software automatically specifies and ranks probability distributions, and then assists the analyst in deciding whether the “best” candidate distribution actually provides a good representation of the data. If no distribution provides a good fit, then ExpertFit can define an empirical distribution. In either case, the selected distribution is put into the proper format for direct input to the analyst´s simulation software. We then consider the case of selecting a distribution in the absence of data. As an example, we show how ExpertFit can be used to specify time-to-failure and repair-time distributions for a machine that is subject to random downtimes