COB 291 EXAM #3 QUESTIONS & ANSWERS

COB 291 EXAM #3 QUESTIONS &
ANSWERS

single server model - Correct Answers --one server
-one que
M/M/1

multi server model - Correct Answers --multiple servers
-one que
M/M/3

3 identical single server - Correct Answers --each server has his or her own que.
M/M/1 M/M/1 M/M/1

Goodness of fit, what should you look for? - Correct Answers -R^2. the higher the
percentage, the higher the variation is described in this model. If it's close to one rather
than zero, then it is a very good relationship.

What to look at to see how strong the significant relationship is - Correct Answers -Look
at multiple R. it does not tell you if it is positive or negative because you have to base it
off if the slope is positive or negative.

Kendall Notation - Correct Answers -Poisson/ Exponential / number of servers
M/M/#

Simple Economic Analysis of Ques - Correct Answers -Total Cost = (waiting cost per
time period x average number of units) + (service cost per time x # of servers)

L - Correct Answers -number of people in the system

Lq - Correct Answers -number of people waiting on line

W - Correct Answers -amount of time spent in the system

Wq - Correct Answers -amount of time you are on line

Po - Correct Answers -probability that no one is on line

P1 - Correct Answers -probability that one person is on line

U - Correct Answers -utilization. chance that the service is currently occupied.