We next will show you the output screen when the Excel template for
queueing simulation is applied to the Littletown bank problem. This routine
runs for 10,000 arrivals, and normally takes a few seconds, but we have
the output stored for you to see immediately. |
The output screen uses notation that was introduced in Chapter 17 of
your textbook for some steady-state expected values (statistical means)
and probabilities in a queueing system. (This same notation is used in
the Queueing Theory Excel templates.) To refresh your memory, this notation
is |
-
= expected
number of customers in the system,
-
=
expected number just in the queue,
-
=
expected waiting time in the system for each individual customer,
-
=
expected waiting time in the queue for each individual customer,
-
=
probability that exactly n customers are in the system.
|
For each of these quantities, the automatic routine uses the data gathered
in the simulation run to compute both a point estimate (the best
available estimate given by a single number) and a 95% confidence interval
(an interval of possible values that will include the value being estimated
95% of the time). |
As you view these measures of performance on the output screen, think
about whether you would tolerate line lengths and waiting times this large
if you were the manager of a bank. |