Explain the major differences between a fixed-time and a next-event simulation model

Answer 1

A simulation model that increments time in fixed intervals is referred to as a fixed-time-increment simulation model. With a fixed-time simulation model, detailed information is lost. For example, two customers arrive in the first minute after a business opens. Their actual arrival times are not recorded so calculations of statistics such as wait-time will not be completely accurate. In addition, many simulation cycles in which nothing happens in the system may be run, which wastes computer time, particularly large simulations.

Next-event simulation models increment time by the occurrence of the next event (time of next arrival, time of next service, and so on). An event is any action that changes the system. For example, there are two types of events—customer arrivals and service completions. When a customer arrives, the number of customers in the system is increased. When a service completion occurs, the number of customers in the system is decreased. At any other time, the system does not change. The simulation time clock is updated whenever an event occurs. Next-event models are used more commonly in practice than fixed-time simulation models, and they are the basis for most commercial simulation software.