Week 1

Question 1

Discrete-Event Simulation

Answer 1

Stochastic: contains random probabilistic elements
-> specify random variables: arrivals, duration of membership, claim size
Dynamic: the process evolves over time
Discrete: changes occur only at discrete points in time when events occur

Question 2

DES Components

Answer 2

• Initialization routine: t=0
• Timing routine: choose next event time, then advance clock
• Event routine: logic for each event type
• Library routines: generate random variables
• Report generator: summary and report results at end
• Main program

(Like Assignment 1 - think!)

Question 3

Components of a Queueing System

Answer 3

1. Arrival process
   
   • interarrivals Ai
   • mean arrival time E(Ai)
2. Service Mechanism
   
   • service times Si
   • mean service time E(S)
   • number of servers c
3. Queue discipline
   
   • FCFS
   • LCFS
   • priority

Question 4

Monte-Carlo Simulation

Answer 4

Stochastic: contains random probabilistic elements
Static: process does not occur over time

Take average of many random variables

Question 5

Update Event List Question

Answer 5

Say when (t+a) you are generating next arrival (and where - think arrival or departure method)
Say when (t+s) you are generating next departure
Also state time and where for additional events!

Make sure you update all events in the simulation

Question 6

Update Counter Variables Question

Answer 6

Example:
nCum = nCum + (t - ts)*n
-> current time - previous event time

Question 7

State Variables

Answer 7

Contain the information on the system content

Question 8

Event

Answer 8

Instantaneous occurrence that may change the state of the system