Event Scheduling :

• In Event Scheduling World View, events and their effects on system state are the prime focus of simulation.

• The mechanism for advancing simulation time and execution of all events in correct chronological order depends on the Future Event List (FEL). FEL contains all the future event notices.

• Scheduling of future events includes :

1. The instant an activity starts.
2. Its duration that can be drawn as a sample from statistical distribution.

3. The end time of an activity.

   Process Interaction :

   • In Process Interaction World View, formalism are typically written from the view point of the moving entities (transactions) that flow through the system.

   • These entities typically arrive, undergo some processing where they capture and release scarce resources, and then exit.

   • At highest level of abstraction, in the process interaction world view, a template is given for the life of transactions or entities as they progress through number of processes or blocks.

   • A process is a time sequence list of events, activities and delays including demands for resources and queuing to wait for resources.

   Activity Scanning :

   • Activity Scanning formalism are written from the view point of the various activities that are performed.

   • This formalism focuses on identifying the nature of activities, the required resources and the conditions under which they occur.

   • In activity scanning all resources are viewed as prerequisites for activities to start. Thus no distinction is made between resources that serve and resources being served.

   • It uses a fix time increment. Activity scanning world view provides locality of state.

   Bootstrapping :

   • In statistics, bootstrapping can refer to any test or metric that relies on random sampling with replacement.

   • Bootstrapping allows assigning measures of accuracy (defined in terms of bias, variance, confidence intervals, prediction error or some other such measure) to sample estimates.

   • This technique allows estimation of the sampling distribution of almost any statistic using random sampling methods.

   Terminating events :

   • Runs for some duration of time $T_E$, where E is a specified event that stops the simulation.

   • Starts at time 0 under well-specified initial conditions.

   • Ends at the stopping time $T_E$.

   • Bank example: Opens at 8:30 am (time 0) with no customers present and 8 of the 11 teller working (initial conditions), and closes at 4:30 pm (Time $T_E$ = 480 minutes).

   • The simulation analyst chooses to consider it a terminating system because the object of interest is one day’s operation.